id
float64 706
1.8k
| title
stringlengths 1
343
| abstract
stringlengths 6
6.09k
| categories
stringlengths 5
125
| processed_abstract
stringlengths 2
5.96k
| tokenized_abstract
stringlengths 8
8.74k
| centroid
stringlengths 2.1k
2.17k
|
|---|---|---|---|---|---|---|
1,803.06967
|
Phenomenology of coupled non linear oscillators
|
A recently introduced model of coupled non linear oscillators in a ring is
revisited in terms of its information processing capabilities. The use of
Lempel-Ziv based entropic measures allows to study thoroughly the complex
patterns appearing in the system for different values of the control
parameters. Such behaviors, resembling cellular automata, have been
characterized both spatially and temporally. Information distance is used to
study the stability of the system to perturbations in the initial conditions
and in the control parameters. The latter is not an issue in cellular automata
theory, where the rules form a numerable set, contrary to the continuous nature
of the parameter space in the system studied in this contribution. The
variation in the density of the digits, as a function of time is also studied.
Local transitions in the control parameter space are also discussed.
|
nlin.CD
|
a recently introduced model of coupled non linear oscillators in a ring is revisited in terms of its information processing capabilities the use of lempelziv based entropic measures allows to study thoroughly the complex patterns appearing in the system for different values of the control parameters such behaviors resembling cellular automata have been characterized both spatially and temporally information distance is used to study the stability of the system to perturbations in the initial conditions and in the control parameters the latter is not an issue in cellular automata theory where the rules form a numerable set contrary to the continuous nature of the parameter space in the system studied in this contribution the variation in the density of the digits as a function of time is also studied local transitions in the control parameter space are also discussed
|
[['a', 'recently', 'introduced', 'model', 'of', 'coupled', 'non', 'linear', 'oscillators', 'in', 'a', 'ring', 'is', 'revisited', 'in', 'terms', 'of', 'its', 'information', 'processing', 'capabilities', 'the', 'use', 'of', 'lempelziv', 'based', 'entropic', 'measures', 'allows', 'to', 'study', 'thoroughly', 'the', 'complex', 'patterns', 'appearing', 'in', 'the', 'system', 'for', 'different', 'values', 'of', 'the', 'control', 'parameters', 'such', 'behaviors', 'resembling', 'cellular', 'automata', 'have', 'been', 'characterized', 'both', 'spatially', 'and', 'temporally', 'information', 'distance', 'is', 'used', 'to', 'study', 'the', 'stability', 'of', 'the', 'system', 'to', 'perturbations', 'in', 'the', 'initial', 'conditions', 'and', 'in', 'the', 'control', 'parameters', 'the', 'latter', 'is', 'not', 'an', 'issue', 'in', 'cellular', 'automata', 'theory', 'where', 'the', 'rules', 'form', 'a', 'numerable', 'set', 'contrary', 'to', 'the', 'continuous', 'nature', 'of', 'the', 'parameter', 'space', 'in', 'the', 'system', 'studied', 'in', 'this', 'contribution', 'the', 'variation', 'in', 'the', 'density', 'of', 'the', 'digits', 'as', 'a', 'function', 'of', 'time', 'is', 'also', 'studied', 'local', 'transitions', 'in', 'the', 'control', 'parameter', 'space', 'are', 'also', 'discussed']]
|
[-0.15707715561449287, 0.10752505620385824, -0.07926697867232368, 0.0598952064630676, -0.02065214325955285, -0.09301260550901723, 0.03536366780620175, 0.32576449583251055, -0.2961598529326294, -0.25550169150659935, 0.11534987179823755, -0.23289270999704456, -0.16567929353055766, 0.171174896745306, -0.06402484378140928, 0.07602133668455373, -0.01651121525717028, 0.07525245353023408, -0.05307268598552445, -0.21409857317322878, 0.3249594575772397, 0.05886414803090512, 0.2962071992835472, -0.00534518800923775, 0.07794698683893402, -0.008075524160886357, -0.03394217147967584, 0.05088307537605798, -0.1332962016521437, 0.09602910157782193, 0.23472600636646576, 0.11545060815376719, 0.2794095832099066, -0.4097448492543303, -0.24519594039486572, 0.12620166043931846, 0.11745772214033541, 0.0847770934991485, -0.0017557077984184885, -0.2749963638861831, 0.0551797815082635, -0.15799879685057688, -0.1152081547720398, -0.05574172157995242, 0.05539979264910648, 0.04962258118291875, -0.2642894918467555, 0.046434211733553346, 0.04706455998980313, 0.05530686655061708, -0.08957962905309706, -0.04935385148198404, -0.013878906981537133, 0.14100169761293976, 0.01191091251211147, -0.006824332428426086, 0.10573219433895868, -0.1361475495584711, -0.1282635581672942, 0.3911398651225747, -0.06056849118288633, -0.2541913964514279, 0.1839109545610443, -0.12952015827168717, -0.13109262736025099, 0.11092932345747626, 0.17425755362475304, 0.11158837642011454, -0.17992808174663524, 0.11438975291805703, -0.020682999788006272, 0.1809576445346256, 0.03745138416696581, 0.08759775792965464, 0.15427536575003065, 0.18911631460294878, 0.04779308294503038, 0.1631763787879843, -0.058068183826939235, -0.15433938484873436, -0.2580545694406459, -0.1336729278479763, -0.17033422643841384, -0.03285154566768031, -0.05256389962193529, -0.17204788387518563, 0.41859862702670875, 0.13886546386781035, 0.21537158638929862, 0.013543862206258361, 0.26315872607209967, 0.14048837316727095, 0.06319084795687696, 0.03065275356949059, 0.22469671507803188, 0.1510559660298817, 0.12253630497298545, -0.22854071294071435, 0.06943695469283694, 0.0587360592518779]
|
1,803.06968
|
Bounded error uniformity of the linear flow on the torus
|
A linear flow on the torus $\mathbb{R}^d / \mathbb{Z}^d$ is uniformly
distributed in the Weyl sense if the direction of the flow has linearly
independent coordinates over $\mathbb{Q}$. In this paper we combine Fourier
analysis and the subspace theorem of Schmidt to prove bounded error uniformity
of linear flows with respect to certain polytopes if, in addition, the
coordinates of the direction are all algebraic. In particular, we show that
there is no van Aardenne--Ehrenfest type theorem for the mod $1$ discrepancy of
continuous curves in any dimension, demonstrating a fundamental difference
between continuous and discrete uniform distribution theory.
|
math.NT
|
a linear flow on the torus mathbbrd mathbbzd is uniformly distributed in the weyl sense if the direction of the flow has linearly independent coordinates over mathbbq in this paper we combine fourier analysis and the subspace theorem of schmidt to prove bounded error uniformity of linear flows with respect to certain polytopes if in addition the coordinates of the direction are all algebraic in particular we show that there is no van aardenneehrenfest type theorem for the mod 1 discrepancy of continuous curves in any dimension demonstrating a fundamental difference between continuous and discrete uniform distribution theory
|
[['a', 'linear', 'flow', 'on', 'the', 'torus', 'mathbbrd', 'mathbbzd', 'is', 'uniformly', 'distributed', 'in', 'the', 'weyl', 'sense', 'if', 'the', 'direction', 'of', 'the', 'flow', 'has', 'linearly', 'independent', 'coordinates', 'over', 'mathbbq', 'in', 'this', 'paper', 'we', 'combine', 'fourier', 'analysis', 'and', 'the', 'subspace', 'theorem', 'of', 'schmidt', 'to', 'prove', 'bounded', 'error', 'uniformity', 'of', 'linear', 'flows', 'with', 'respect', 'to', 'certain', 'polytopes', 'if', 'in', 'addition', 'the', 'coordinates', 'of', 'the', 'direction', 'are', 'all', 'algebraic', 'in', 'particular', 'we', 'show', 'that', 'there', 'is', 'no', 'van', 'aardenneehrenfest', 'type', 'theorem', 'for', 'the', 'mod', '1', 'discrepancy', 'of', 'continuous', 'curves', 'in', 'any', 'dimension', 'demonstrating', 'a', 'fundamental', 'difference', 'between', 'continuous', 'and', 'discrete', 'uniform', 'distribution', 'theory']]
|
[-0.16937212861075843, 0.11603263782855776, -0.10585365935046341, -0.003186414309911737, -0.04221385089949388, -0.11213229013818134, 0.0039035886785341906, 0.36635987288270566, -0.3536702701149835, -0.1715213417984094, 0.09429136256461713, -0.27235756621974494, -0.12176728106737521, 0.20444430531357827, -0.14076260999613202, 0.05892391937794452, 0.013821928905918426, 0.0569489024214677, -0.09673705430864596, -0.28966332007122714, 0.34351065356558014, -0.07460423013358616, 0.26491837454095635, 0.007886200759214224, 0.13977587306583972, 0.04690151410561401, -0.04387804402096063, 0.03489298024934899, -0.13533091761410948, 0.12914058741076476, 0.25081471239514264, 0.05395841295403349, 0.2685387255527924, -0.3695025176923607, -0.1940936385509894, 0.19237852789768853, 0.13324402107079467, 0.031893867279220486, -0.013900125018781838, -0.20009281604848417, 0.1326971804703941, -0.10645998334608127, -0.15944072344945265, -0.04388250497928292, 0.07188617911900289, 0.07227866205665254, -0.2567322713985425, 0.07634130880697486, 0.15007785676268035, 0.12130658223879398, -0.06002300185122594, -0.06848747502969213, -0.027959552900769662, 0.08018006681411806, 0.04568591142150084, 0.08233650181365688, 0.05245039549646611, -0.052072685929591356, -0.10960250190511998, 0.36459202666469304, -0.06615220062847528, -0.26186796922966377, 0.14500147265564536, -0.19485639174440011, -0.13946751213258074, 0.09499658525143702, 0.14807916364450122, 0.10902400257200309, -0.05899406524048638, 0.18827889680972842, -0.13530451763114057, 0.17560151417154013, 0.10513305889212132, 0.004464922337216738, 0.1153898844687441, 0.04742924638390157, 0.18005153017368206, 0.10945702314535252, -0.052029408642916566, -0.0850086111680979, -0.36490909933813453, -0.1643793539086491, -0.20868139790932735, 0.06905033578736151, -0.14539498171844692, -0.1795090804087747, 0.364692074371521, 0.07724098240975867, 0.18853616220492525, 0.09745376746466662, 0.23282005808546602, 0.11200030868604165, -0.011422734726796445, 0.13793201597657093, 0.19143574691819237, 0.18234223328031524, 0.04675297731816884, -0.16369414635329055, 0.015217332313432521, 0.13914346875014988]
|
1,803.06969
|
Comparing Dynamics: Deep Neural Networks versus Glassy Systems
|
We analyze numerically the training dynamics of deep neural networks (DNN) by
using methods developed in statistical physics of glassy systems. The two main
issues we address are (1) the complexity of the loss landscape and of the
dynamics within it, and (2) to what extent DNNs share similarities with glassy
systems. Our findings, obtained for different architectures and datasets,
suggest that during the training process the dynamics slows down because of an
increasingly large number of flat directions. At large times, when the loss is
approaching zero, the system diffuses at the bottom of the landscape. Despite
some similarities with the dynamics of mean-field glassy systems, in
particular, the absence of barrier crossing, we find distinctive dynamical
behaviors in the two cases, showing that the statistical properties of the
corresponding loss and energy landscapes are different. In contrast, when the
network is under-parametrized we observe a typical glassy behavior, thus
suggesting the existence of different phases depending on whether the network
is under-parametrized or over-parametrized.
|
stat.ML cond-mat.dis-nn cs.LG
|
we analyze numerically the training dynamics of deep neural networks dnn by using methods developed in statistical physics of glassy systems the two main issues we address are 1 the complexity of the loss landscape and of the dynamics within it and 2 to what extent dnns share similarities with glassy systems our findings obtained for different architectures and datasets suggest that during the training process the dynamics slows down because of an increasingly large number of flat directions at large times when the loss is approaching zero the system diffuses at the bottom of the landscape despite some similarities with the dynamics of meanfield glassy systems in particular the absence of barrier crossing we find distinctive dynamical behaviors in the two cases showing that the statistical properties of the corresponding loss and energy landscapes are different in contrast when the network is underparametrized we observe a typical glassy behavior thus suggesting the existence of different phases depending on whether the network is underparametrized or overparametrized
|
[['we', 'analyze', 'numerically', 'the', 'training', 'dynamics', 'of', 'deep', 'neural', 'networks', 'dnn', 'by', 'using', 'methods', 'developed', 'in', 'statistical', 'physics', 'of', 'glassy', 'systems', 'the', 'two', 'main', 'issues', 'we', 'address', 'are', '1', 'the', 'complexity', 'of', 'the', 'loss', 'landscape', 'and', 'of', 'the', 'dynamics', 'within', 'it', 'and', '2', 'to', 'what', 'extent', 'dnns', 'share', 'similarities', 'with', 'glassy', 'systems', 'our', 'findings', 'obtained', 'for', 'different', 'architectures', 'and', 'datasets', 'suggest', 'that', 'during', 'the', 'training', 'process', 'the', 'dynamics', 'slows', 'down', 'because', 'of', 'an', 'increasingly', 'large', 'number', 'of', 'flat', 'directions', 'at', 'large', 'times', 'when', 'the', 'loss', 'is', 'approaching', 'zero', 'the', 'system', 'diffuses', 'at', 'the', 'bottom', 'of', 'the', 'landscape', 'despite', 'some', 'similarities', 'with', 'the', 'dynamics', 'of', 'meanfield', 'glassy', 'systems', 'in', 'particular', 'the', 'absence', 'of', 'barrier', 'crossing', 'we', 'find', 'distinctive', 'dynamical', 'behaviors', 'in', 'the', 'two', 'cases', 'showing', 'that', 'the', 'statistical', 'properties', 'of', 'the', 'corresponding', 'loss', 'and', 'energy', 'landscapes', 'are', 'different', 'in', 'contrast', 'when', 'the', 'network', 'is', 'underparametrized', 'we', 'observe', 'a', 'typical', 'glassy', 'behavior', 'thus', 'suggesting', 'the', 'existence', 'of', 'different', 'phases', 'depending', 'on', 'whether', 'the', 'network', 'is', 'underparametrized', 'or', 'overparametrized']]
|
[-0.10486028294601454, 0.13175989009687328, -0.09009551209477117, 0.09286164414397274, 0.010530514920857258, -0.13762267601815414, 0.0318223322903533, 0.37968866304471727, -0.3012727201751592, -0.31561658438508083, 0.08509852529202429, -0.2901458943648854, -0.1885807841757835, 0.16505664589718302, -0.0313156796718675, 0.043773335143469455, 0.07285538110910438, 0.012248632632956908, -0.08320867149343873, -0.2555211916531822, 0.3543804811154742, 0.022806930615355134, 0.3195318912394436, 0.046337661941013325, 0.07641324878772493, -0.04824360325171544, 0.06819299226711936, 0.0012179640237530004, -0.11011122888361924, 0.09684028039777243, 0.20777128811601958, 0.10655085238480441, 0.31120214300093857, -0.4575312341018239, -0.24030937222627605, 0.10078432773262626, 0.14997186962367468, 0.11205359296094151, -0.010944950940916541, -0.25411749965931496, 0.07494786180017754, -0.10402255514835394, -0.11100661279008973, -0.07666941920846201, 0.01043196041108586, 0.05339203329888888, -0.19400666549336165, 0.08608965466662151, 0.06292552624246327, 0.08159069802254303, -0.05943994861658344, -0.1179764020823158, -0.026734965377793896, 0.15414447437655238, 0.08956189651348168, -0.017549420021745525, 0.13824018323510068, -0.2063642939358876, -0.1064844161936468, 0.3556836772903164, -0.022376589500487258, -0.15023017646290543, 0.2650266063524546, -0.13388998850922046, -0.1334792249097784, 0.13352295253056715, 0.19096607485255113, 0.07701952765673035, -0.13259232237103832, 0.0410356076800537, 0.028392138699262697, 0.15846810675589595, 0.01033386979223706, 0.03750716119709357, 0.21692966419362986, 0.25810779246825316, 0.017447565431655498, 0.15953563764214335, -0.10659709336838072, -0.16947457120078047, -0.2407286309427014, -0.09997794535202713, -0.1804049862108602, 0.02662631680283173, -0.10517399777656863, -0.13815635372884572, 0.4094363050648897, 0.18549202865475176, 0.23551649725768806, 0.07849747414570074, 0.24910178441531594, 0.061719689235338236, 0.060428723763878936, 0.10038840187083158, 0.24860979785674917, 0.054440673589763205, 0.12467850670048104, -0.24648998969691668, 0.07565623318645875, -0.02386630272276972]
|
1,803.0697
|
Higher symmetries of symplectic Dirac operator
|
We construct in projective differential geometry of the real dimension $2$
higher symmetry algebra of the symplectic Dirac operator
${D}\kern-0.5em\raise0.22ex\hbox{/}_s$ acting on symplectic spinors. The higher
symmetry differential operators correspond to the solution space of a class of
projectively invariant overdetermined operators of arbitrarily high order
acting on symmetric tensors. The higher symmetry algebra structure corresponds
to a completely prime primitive ideal having as its associated variety the
minimal nilpotent orbit of $\mathfrak{sl}(3,{\mathbb{R}})$.
|
math.DG math-ph math.FA math.MP math.RT math.SG
|
we construct in projective differential geometry of the real dimension 2 higher symmetry algebra of the symplectic dirac operator dkern05emraise022exhbox_s acting on symplectic spinors the higher symmetry differential operators correspond to the solution space of a class of projectively invariant overdetermined operators of arbitrarily high order acting on symmetric tensors the higher symmetry algebra structure corresponds to a completely prime primitive ideal having as its associated variety the minimal nilpotent orbit of mathfraksl3mathbbr
|
[['we', 'construct', 'in', 'projective', 'differential', 'geometry', 'of', 'the', 'real', 'dimension', '2', 'higher', 'symmetry', 'algebra', 'of', 'the', 'symplectic', 'dirac', 'operator', 'dkern05emraise022exhbox_s', 'acting', 'on', 'symplectic', 'spinors', 'the', 'higher', 'symmetry', 'differential', 'operators', 'correspond', 'to', 'the', 'solution', 'space', 'of', 'a', 'class', 'of', 'projectively', 'invariant', 'overdetermined', 'operators', 'of', 'arbitrarily', 'high', 'order', 'acting', 'on', 'symmetric', 'tensors', 'the', 'higher', 'symmetry', 'algebra', 'structure', 'corresponds', 'to', 'a', 'completely', 'prime', 'primitive', 'ideal', 'having', 'as', 'its', 'associated', 'variety', 'the', 'minimal', 'nilpotent', 'orbit', 'of', 'mathfraksl3mathbbr']]
|
[-0.23459885967239527, 0.10538027493912779, -0.032771459833102326, 0.055918340951624054, -0.17510768330433, -0.15402970463693352, -0.10298521229079072, 0.2951812528034436, -0.310087790581542, -0.2271084422376794, 0.13622549373794243, -0.2742586391387691, -0.13525826583655787, 0.12149409279489601, -0.08512981133092798, 0.0479416249895429, -0.015184544784371073, 0.14137448451127593, -0.21815195152352393, -0.23283430406312183, 0.49807797865548603, -0.010921771926674205, 0.22636893187308502, -0.05180316524002963, 0.19769598472155106, -0.010018715084018841, 0.012314813687059452, -0.0546875189613505, -0.060773397848324875, 0.14735944616988722, 0.2837980387037174, 0.01064886886324786, 0.11897191071954989, -0.39159072913281934, -0.08514493230310544, 0.19036934026320215, 0.11865001718815364, 0.021317782011670127, -0.025857743797299097, -0.28818723850581845, 0.09024661116328248, -0.216143764660392, -0.2466928798862746, -0.10576008371746456, 0.04085406710879064, -0.0885123355760121, -0.21132243087951383, 0.03266695379213968, 0.10258074422222628, 0.16601889621151586, -0.11088969986262719, -0.0733235612289052, -0.15477148490682455, 0.03919396140042063, -0.05541704896785004, 0.0011653784846126195, 0.11312700637360432, -0.043055656331617544, -0.14263054708832165, 0.4185166912428825, -0.057174431758565486, -0.33619738809934907, 0.12565139690118934, -0.22488474449746207, -0.12684678514553627, 0.1633944494984257, 0.16842659573319932, 0.16877679048027372, -0.011559120498263133, 0.23439316504018406, -0.09525325998637668, 0.045311120697821845, 0.08423002085215608, 0.03157954424304862, 0.12110155914634677, 0.05395144267453694, 0.1782208217412863, 0.09191682566823044, 0.05905876088228313, -0.08139898129870039, -0.37486193103479665, -0.2132686863548424, -0.114547613844223, 0.17939418423133838, -0.14882506808252927, -0.18074722302106905, 0.4070649982797323, 0.03575500224152921, 0.1973109230346663, 0.039991967380046844, 0.19128730095608135, 0.12527086156663078, 0.13317368411078628, 0.013077073813330802, 0.12477873114239373, 0.25220755642135695, 0.0006004146785593368, -0.20333209905681582, -0.0774822370673884, 0.20648095245853487]
|
1,803.06971
|
What Doubling Tricks Can and Can't Do for Multi-Armed Bandits
|
An online reinforcement learning algorithm is anytime if it does not need to
know in advance the horizon T of the experiment. A well-known technique to
obtain an anytime algorithm from any non-anytime algorithm is the "Doubling
Trick". In the context of adversarial or stochastic multi-armed bandits, the
performance of an algorithm is measured by its regret, and we study two
families of sequences of growing horizons (geometric and exponential) to
generalize previously known results that certain doubling tricks can be used to
conserve certain regret bounds. In a broad setting, we prove that a geometric
doubling trick can be used to conserve (minimax) bounds in $R\_T = O(\sqrt{T})$
but cannot conserve (distribution-dependent) bounds in $R\_T = O(\log T)$. We
give insights as to why exponential doubling tricks may be better, as they
conserve bounds in $R\_T = O(\log T)$, and are close to conserving bounds in
$R\_T = O(\sqrt{T})$.
|
stat.ML cs.LG math.ST stat.TH
|
an online reinforcement learning algorithm is anytime if it does not need to know in advance the horizon t of the experiment a wellknown technique to obtain an anytime algorithm from any nonanytime algorithm is the doubling trick in the context of adversarial or stochastic multiarmed bandits the performance of an algorithm is measured by its regret and we study two families of sequences of growing horizons geometric and exponential to generalize previously known results that certain doubling tricks can be used to conserve certain regret bounds in a broad setting we prove that a geometric doubling trick can be used to conserve minimax bounds in r_t osqrtt but cannot conserve distributiondependent bounds in r_t olog t we give insights as to why exponential doubling tricks may be better as they conserve bounds in r_t olog t and are close to conserving bounds in r_t osqrtt
|
[['an', 'online', 'reinforcement', 'learning', 'algorithm', 'is', 'anytime', 'if', 'it', 'does', 'not', 'need', 'to', 'know', 'in', 'advance', 'the', 'horizon', 't', 'of', 'the', 'experiment', 'a', 'wellknown', 'technique', 'to', 'obtain', 'an', 'anytime', 'algorithm', 'from', 'any', 'nonanytime', 'algorithm', 'is', 'the', 'doubling', 'trick', 'in', 'the', 'context', 'of', 'adversarial', 'or', 'stochastic', 'multiarmed', 'bandits', 'the', 'performance', 'of', 'an', 'algorithm', 'is', 'measured', 'by', 'its', 'regret', 'and', 'we', 'study', 'two', 'families', 'of', 'sequences', 'of', 'growing', 'horizons', 'geometric', 'and', 'exponential', 'to', 'generalize', 'previously', 'known', 'results', 'that', 'certain', 'doubling', 'tricks', 'can', 'be', 'used', 'to', 'conserve', 'certain', 'regret', 'bounds', 'in', 'a', 'broad', 'setting', 'we', 'prove', 'that', 'a', 'geometric', 'doubling', 'trick', 'can', 'be', 'used', 'to', 'conserve', 'minimax', 'bounds', 'in', 'r_t', 'osqrtt', 'but', 'can', 'not', 'conserve', 'distributiondependent', 'bounds', 'in', 'r_t', 'olog', 't', 'we', 'give', 'insights', 'as', 'to', 'why', 'exponential', 'doubling', 'tricks', 'may', 'be', 'better', 'as', 'they', 'conserve', 'bounds', 'in', 'r_t', 'olog', 't', 'and', 'are', 'close', 'to', 'conserving', 'bounds', 'in', 'r_t', 'osqrtt']]
|
[-0.10623269420187308, 0.11048394810575402, -0.1361953691270024, 0.17537374738268938, -0.15409750181365095, -0.20994131619506196, 0.0838043176607318, 0.38429105041484024, -0.2919949950165536, -0.3563905109408988, 0.13791852566646412, -0.2443295864209737, -0.16007491653587363, 0.20477253886111949, -0.19716605918532978, 0.08036654402321676, 0.011540055396162893, 0.08725934528126955, -0.05874265058441343, -0.33590521253262684, 0.20784426307025022, 0.06473030697248161, 0.20190961304446045, 0.05705733384461818, 0.07826489166273697, -0.033250015244934046, 0.04088263729051368, 0.011735017357189974, -0.19786301663208017, 0.052058334834714205, 0.26629071214478717, 0.20180345385826562, 0.29068149954769507, -0.400879024604514, -0.14768608541814737, 0.20744544563078232, 0.20782718529317956, 0.10651243853618786, -0.014464566016837647, -0.25752068410487206, 0.08639960190638492, -0.13941600788161412, -0.08144918832073167, -0.1285562072338358, -0.03481584035612847, 0.005806178563395643, -0.34320037771807343, 0.030302833191642207, 0.13985123621516746, -0.036762492249604976, -0.026829392543183766, -0.10398015585944873, 0.047321255459156754, 0.09086119126662459, 0.08169958990685999, 0.06712229375261813, 0.10446662804724215, -0.05484169950606684, -0.2073720354803723, 0.29649123197982774, -0.10757103079470666, -0.2021787721115126, 0.14142949502414398, -0.12345292232611714, -0.15311369756619408, 0.12366229881953499, 0.2193687811816009, 0.16963558078883853, -0.14846658337644417, 0.13858707352224037, -0.07196837597309727, 0.13295928301442772, 0.08696401883427003, 0.06570681197288102, 0.05384216658062978, 0.13280165950649686, 0.20663034170866013, 0.11470439108184297, 0.007686296027003826, -0.10921104413406184, -0.2871448606251076, -0.11663892012638079, -0.2017681466874807, 0.04282517815092483, -0.15428542844882978, -0.1374182767156601, 0.26963796983281635, 0.13005325077691637, 0.23757280854106408, 0.15180372533209827, 0.279387831707064, 0.10730167913524918, 0.10194818490609042, 0.19173864228202409, 0.22369128725593526, 0.059559130411250646, 0.08880354564203179, -0.16889343187627573, 0.11460809273468267, 0.10578349173668619]
|
1,803.06972
|
Taxonomy and Jargon in SETI as an Interdisciplinary Field of Study
|
While SETI is often thought of as a part of radio astronomy with optical
SETI, artifact SETI, METI, and other approaches to finding intelligent life
considered to be allied fields, SETI is better understood as an
interdisciplinary field with many subfields, approaches, and components. In
particular, Robert Bradbury has argued for a broad view of SETI between two
extremes: "orthodox SETI," or radio communication SETI, and a "Dysonian
Approach" that searches for the extreme effects of alien life on its
environment. Here, I build on these ideas and attempt to organize the
terminology and efforts of SETI within a single framework for SETI as an
interdisciplinary and multipronged approach.
|
physics.pop-ph
|
while seti is often thought of as a part of radio astronomy with optical seti artifact seti meti and other approaches to finding intelligent life considered to be allied fields seti is better understood as an interdisciplinary field with many subfields approaches and components in particular robert bradbury has argued for a broad view of seti between two extremes orthodox seti or radio communication seti and a dysonian approach that searches for the extreme effects of alien life on its environment here i build on these ideas and attempt to organize the terminology and efforts of seti within a single framework for seti as an interdisciplinary and multipronged approach
|
[['while', 'seti', 'is', 'often', 'thought', 'of', 'as', 'a', 'part', 'of', 'radio', 'astronomy', 'with', 'optical', 'seti', 'artifact', 'seti', 'meti', 'and', 'other', 'approaches', 'to', 'finding', 'intelligent', 'life', 'considered', 'to', 'be', 'allied', 'fields', 'seti', 'is', 'better', 'understood', 'as', 'an', 'interdisciplinary', 'field', 'with', 'many', 'subfields', 'approaches', 'and', 'components', 'in', 'particular', 'robert', 'bradbury', 'has', 'argued', 'for', 'a', 'broad', 'view', 'of', 'seti', 'between', 'two', 'extremes', 'orthodox', 'seti', 'or', 'radio', 'communication', 'seti', 'and', 'a', 'dysonian', 'approach', 'that', 'searches', 'for', 'the', 'extreme', 'effects', 'of', 'alien', 'life', 'on', 'its', 'environment', 'here', 'i', 'build', 'on', 'these', 'ideas', 'and', 'attempt', 'to', 'organize', 'the', 'terminology', 'and', 'efforts', 'of', 'seti', 'within', 'a', 'single', 'framework', 'for', 'seti', 'as', 'an', 'interdisciplinary', 'and', 'multipronged', 'approach']]
|
[-0.051579233942502134, 0.10619765140971707, -0.09610897258197496, 0.10904187050438699, -0.1769888347197418, -0.1649476483148104, 0.08390258356006047, 0.40611676138680464, -0.20577514675710726, -0.3331526684309911, 0.12354499566338854, -0.24286928268815947, -0.2062398872675733, 0.2333914358782958, -0.046330178538850006, -0.04345853731875658, -0.02740913004093214, -0.03441005907611016, 0.02239087210549469, -0.19467521308485522, 0.2416481028114437, 0.09809055022143442, 0.28956590630669454, 0.02928589197695939, 0.052364967814689384, -0.00038994022927016294, -0.09236522162025539, -0.019777490665555137, -0.035479212002820705, 0.1391653310968925, 0.38363542305220155, 0.2755708320775505, 0.39594410920789075, -0.4273546168563563, -0.23832882551151677, 0.0978469145286683, 0.13682501599483124, 0.06006966194419891, -0.03062030004653567, -0.34324181697613326, -0.036964307774131726, -0.18188681687578695, -0.176356529671733, -0.014153869583382519, 0.0735882708830588, 0.0133366574508719, -0.17435792740434408, -0.05281314874973592, 0.018738784777094532, 0.14869272024926106, -0.04910212717288165, -0.1499531486695376, 0.12495739901985187, 0.12017695032649699, 0.09022484503637299, 0.05738322886236764, 0.1336593627246148, -0.1540054912003902, -0.2260579871304265, 0.42196467990448716, -0.015975381194297738, -0.09402148106024352, 0.2653176992824045, -0.08228050428656263, -0.17478570438186647, 0.053975836762628696, 0.16818104520089788, 0.08538337866134874, -0.13324938138889217, 0.06905548853282774, 0.026396762477148564, 0.11258602784367154, 0.03326962685955842, 0.08699083076191878, 0.33751817074937557, 0.1785628740556128, 0.08653393037153415, 0.009051191624266805, -0.0995742878897987, -0.07921660243994941, -0.22735910169318865, -0.15040253072233717, -0.2087749862710202, 0.07399984601235718, 0.045284754341124306, -0.15791616052252436, 0.34681588100320704, 0.18441974715150278, 0.03944245134608461, 0.009665247437398914, 0.33730275695716294, 0.01902072883206804, 0.08326535369910368, 0.03867341954380684, 0.2770197971044706, 0.05139327269269649, 0.1591832303941899, -0.10374833219428334, 0.050785607033528794, -0.050450433686443974]
|
1,803.06973
|
The carbon footprint of distributed cloud storage
|
The ICT (Information Communication Technologies) ecosystem is estimated to be
responsible, as of today, for 10% of the total worldwide energy demand -
equivalent to the combined energy production of Germany and Japan. Cloud
storage, mainly operated through large and densely-packed data centers,
constitutes a non-negligible part of it. However, since the cloud is a
fast-inflating market and the energy-efficiency of data centers is mostly an
insensitive issue for the collectivity, its carbon footprint shows no signs of
slowing down. In this paper, we analyze a novel paradigm for cloud storage
(implemented by Cubbit, http://cubbit.io), in which data are stored and
distributed over a network of p2p-interacting ARM-based single-board devices.
We compare Cubbit's distributed cloud to the traditional centralized solution
in terms of environmental footprint and energy efficiency. We demonstrate that,
compared to the centralized cloud, the distributed architecture of Cubbit has a
carbon footprint reduced of a 77% factor for data storage and of a 50% factor
for data transfers. These results provide an example of how a radical paradigm
shift in a large-reach technology can benefit both the final consumer as well
as our society as a whole.
|
cs.DC
|
the ict information communication technologies ecosystem is estimated to be responsible as of today for 10 of the total worldwide energy demand equivalent to the combined energy production of germany and japan cloud storage mainly operated through large and denselypacked data centers constitutes a nonnegligible part of it however since the cloud is a fastinflating market and the energyefficiency of data centers is mostly an insensitive issue for the collectivity its carbon footprint shows no signs of slowing down in this paper we analyze a novel paradigm for cloud storage implemented by cubbit httpcubbitio in which data are stored and distributed over a network of p2pinteracting armbased singleboard devices we compare cubbits distributed cloud to the traditional centralized solution in terms of environmental footprint and energy efficiency we demonstrate that compared to the centralized cloud the distributed architecture of cubbit has a carbon footprint reduced of a 77 factor for data storage and of a 50 factor for data transfers these results provide an example of how a radical paradigm shift in a largereach technology can benefit both the final consumer as well as our society as a whole
|
[['the', 'ict', 'information', 'communication', 'technologies', 'ecosystem', 'is', 'estimated', 'to', 'be', 'responsible', 'as', 'of', 'today', 'for', '10', 'of', 'the', 'total', 'worldwide', 'energy', 'demand', 'equivalent', 'to', 'the', 'combined', 'energy', 'production', 'of', 'germany', 'and', 'japan', 'cloud', 'storage', 'mainly', 'operated', 'through', 'large', 'and', 'denselypacked', 'data', 'centers', 'constitutes', 'a', 'nonnegligible', 'part', 'of', 'it', 'however', 'since', 'the', 'cloud', 'is', 'a', 'fastinflating', 'market', 'and', 'the', 'energyefficiency', 'of', 'data', 'centers', 'is', 'mostly', 'an', 'insensitive', 'issue', 'for', 'the', 'collectivity', 'its', 'carbon', 'footprint', 'shows', 'no', 'signs', 'of', 'slowing', 'down', 'in', 'this', 'paper', 'we', 'analyze', 'a', 'novel', 'paradigm', 'for', 'cloud', 'storage', 'implemented', 'by', 'cubbit', 'httpcubbitio', 'in', 'which', 'data', 'are', 'stored', 'and', 'distributed', 'over', 'a', 'network', 'of', 'p2pinteracting', 'armbased', 'singleboard', 'devices', 'we', 'compare', 'cubbits', 'distributed', 'cloud', 'to', 'the', 'traditional', 'centralized', 'solution', 'in', 'terms', 'of', 'environmental', 'footprint', 'and', 'energy', 'efficiency', 'we', 'demonstrate', 'that', 'compared', 'to', 'the', 'centralized', 'cloud', 'the', 'distributed', 'architecture', 'of', 'cubbit', 'has', 'a', 'carbon', 'footprint', 'reduced', 'of', 'a', '77', 'factor', 'for', 'data', 'storage', 'and', 'of', 'a', '50', 'factor', 'for', 'data', 'transfers', 'these', 'results', 'provide', 'an', 'example', 'of', 'how', 'a', 'radical', 'paradigm', 'shift', 'in', 'a', 'largereach', 'technology', 'can', 'benefit', 'both', 'the', 'final', 'consumer', 'as', 'well', 'as', 'our', 'society', 'as', 'a', 'whole']]
|
[-0.14557945671117772, 0.058640019960636225, -0.038517683681745365, 0.03177661837940872, -0.009561550562976154, -0.0885583673025594, 0.10014173354516011, 0.3601868482163319, -0.28136805936714615, -0.3393015064501234, 0.133786915719591, -0.2826369800451365, -0.058979947794776326, 0.21299448098148127, -0.08953526504542474, 0.017680273930846643, 0.07574572437890591, 0.012770998728068821, 0.023693202548771636, -0.22989693020501142, 0.2641116425050883, 0.1324431976664218, 0.3690523864934221, 0.09825957838988321, 0.09175011679430359, -0.04495196393818932, -0.024777382428970207, -0.01083476512800329, -0.035137890270282066, 0.17128941262202277, 0.297266934722007, 0.17309871000227528, 0.29608641652605283, -0.46023451099888635, -0.16311488925622633, 0.09568778870647753, 0.15398427486102415, 0.07299532457497893, -0.08070101487900612, -0.22134259781175916, 0.08984549945747418, -0.26492988339185225, -0.12508870578736545, -0.050456118637537274, 0.04600891524895125, 0.029156828178271938, -0.24871817017792835, 0.04851248525185408, -0.0078066517899559994, 0.07186333918150842, -0.05310726241289528, -0.10896808731850686, -0.022226331800294038, 0.12671479731695828, -0.012945308307810063, 0.028865750460082072, 0.19761962057308774, -0.15195083595264786, -0.10139195702376437, 0.4202989680119432, -0.04466869787423063, -0.0955152503716258, 0.15053529998384785, -0.052232237645312325, -0.11463979020034178, 0.10620668465987994, 0.22831433519188846, 0.04979770361883361, -0.19888876829741542, 0.05439747202051497, 0.01634475370679706, 0.1902648454204529, 0.022404350817541253, 0.07118261814601003, 0.19432562367432843, 0.23871736224884024, 0.09213936088893276, 0.13866824024308289, -0.10480773604249807, -0.12696379196723273, -0.20963154130124048, -0.1817642410047823, -0.18375239757421827, 0.03398805968258735, -0.0714824640540378, -0.11436777357472577, 0.3574189567416497, 0.13000341518884423, 0.18774569772982172, 0.014347607516146336, 0.35242718762134784, 0.059713001984074345, 0.15516668531255653, 0.11937918523735888, 0.2115196176564096, 0.03228526966196004, 0.19935950679783862, -0.17782124896932924, 0.06420436688535079, -0.07971852635555379]
|
1,803.06974
|
Quasi boundary triples, self-adjoint extensions, and Robin Laplacians on
the half-space
|
In this note self-adjoint extensions of symmetric operators are investigated
by using the abstract technique of quasi boundary triples and their Weyl
functions. The main result is an extension of Theorem 2.6 in [5] which provides
sufficient conditions on the parameter in the boundary space to induce
self-adjoint realizations. As an example self-adjoint Robin Laplacians on the
half-space with boundary conditions involving an unbounded coefficient are
considered.
|
math.SP
|
in this note selfadjoint extensions of symmetric operators are investigated by using the abstract technique of quasi boundary triples and their weyl functions the main result is an extension of theorem 26 in 5 which provides sufficient conditions on the parameter in the boundary space to induce selfadjoint realizations as an example selfadjoint robin laplacians on the halfspace with boundary conditions involving an unbounded coefficient are considered
|
[['in', 'this', 'note', 'selfadjoint', 'extensions', 'of', 'symmetric', 'operators', 'are', 'investigated', 'by', 'using', 'the', 'abstract', 'technique', 'of', 'quasi', 'boundary', 'triples', 'and', 'their', 'weyl', 'functions', 'the', 'main', 'result', 'is', 'an', 'extension', 'of', 'theorem', '26', 'in', '5', 'which', 'provides', 'sufficient', 'conditions', 'on', 'the', 'parameter', 'in', 'the', 'boundary', 'space', 'to', 'induce', 'selfadjoint', 'realizations', 'as', 'an', 'example', 'selfadjoint', 'robin', 'laplacians', 'on', 'the', 'halfspace', 'with', 'boundary', 'conditions', 'involving', 'an', 'unbounded', 'coefficient', 'are', 'considered']]
|
[-0.15598097426900223, 0.12576472357418492, -0.044425218546790865, 0.044386119401054594, -0.09942186748567246, -0.12408632489004687, -0.06935382642741524, 0.35355811643956314, -0.2533310993449457, -0.2278475312710698, 0.1630745558224535, -0.26740199968274403, -0.1324340292780813, 0.20032859870246542, -0.11163943138237653, 0.08604949131719213, 0.0556746313987828, 0.07475433755429711, -0.09844647239156958, -0.21467577471439517, 0.44505313361313803, -0.01974147800078143, 0.18282239574160594, 0.09433420761418876, 0.0321569565836507, 0.00820425794279175, -0.019406342993615502, -0.05222234423941265, -0.16064379264169665, 0.07660987826564641, 0.25217639825501437, 0.02098082785091516, 0.2503534795633003, -0.42750089275025166, -0.18219725071772266, 0.14100704071070277, 0.07655962277203798, -0.004250651498241767, -0.002101367815578384, -0.3104290987795858, 0.06950794679543643, -0.13124022026782606, -0.19640682034416876, -0.03156328859301145, 0.0034096359445560556, -0.03907913970413493, -0.33267029923901187, 0.09469124954888847, 0.12757152310614264, 0.08687751106361845, -0.1596288569827578, -0.09674623787208501, -0.04107415280652357, 0.03921353609176047, -0.014618772794423042, -0.039211562487171656, 0.0377693598631269, -0.013613206073780781, -0.11801407906685525, 0.3345024604767339, -0.06518290001454193, -0.3144552932857578, 0.16640122339073846, -0.11561600068139273, -0.0848047900527938, 0.0406147809421171, 0.10110631578170987, 0.18949285141234076, -0.16612238213141908, 0.18548774053325265, -0.09498303433108742, 0.06885698773557626, 0.10630715290890701, 0.046623980876669954, 0.0950509582354284, 0.07034310354475877, 0.17090759286656976, 0.18449241631356356, 0.04129785220416735, -0.09024369873023078, -0.4139623858257016, -0.14386968273641682, -0.16698649497841722, 0.03807509632467521, -0.13413038894985002, -0.26140312529203774, 0.3866469355703179, 0.11975061281500801, 0.2316617441586038, 0.0009587977182314689, 0.19612797132846135, 0.1852013257465937, 0.06608101554951672, 0.04517781954091876, 0.14843990503629642, 0.22003107924195034, 0.0875210154718205, -0.15104495524428785, -0.007876843009005064, 0.16500006458346747]
|
1,803.06975
|
Technical Report: When Does Machine Learning FAIL? Generalized
Transferability for Evasion and Poisoning Attacks
|
Recent results suggest that attacks against supervised machine learning
systems are quite effective, while defenses are easily bypassed by new attacks.
However, the specifications for machine learning systems currently lack precise
adversary definitions, and the existing attacks make diverse, potentially
unrealistic assumptions about the strength of the adversary who launches them.
We propose the FAIL attacker model, which describes the adversary's knowledge
and control along four dimensions. Our model allows us to consider a wide range
of weaker adversaries who have limited control and incomplete knowledge of the
features, learning algorithms and training instances utilized. To evaluate the
utility of the FAIL model, we consider the problem of conducting targeted
poisoning attacks in a realistic setting: the crafted poison samples must have
clean labels, must be individually and collectively inconspicuous, and must
exhibit a generalized form of transferability, defined by the FAIL model. By
taking these constraints into account, we design StingRay, a targeted poisoning
attack that is practical against 4 machine learning applications, which use 3
different learning algorithms, and can bypass 2 existing defenses. Conversely,
we show that a prior evasion attack is less effective under generalized
transferability. Such attack evaluations, under the FAIL adversary model, may
also suggest promising directions for future defenses.
|
cs.CR cs.LG
|
recent results suggest that attacks against supervised machine learning systems are quite effective while defenses are easily bypassed by new attacks however the specifications for machine learning systems currently lack precise adversary definitions and the existing attacks make diverse potentially unrealistic assumptions about the strength of the adversary who launches them we propose the fail attacker model which describes the adversarys knowledge and control along four dimensions our model allows us to consider a wide range of weaker adversaries who have limited control and incomplete knowledge of the features learning algorithms and training instances utilized to evaluate the utility of the fail model we consider the problem of conducting targeted poisoning attacks in a realistic setting the crafted poison samples must have clean labels must be individually and collectively inconspicuous and must exhibit a generalized form of transferability defined by the fail model by taking these constraints into account we design stingray a targeted poisoning attack that is practical against 4 machine learning applications which use 3 different learning algorithms and can bypass 2 existing defenses conversely we show that a prior evasion attack is less effective under generalized transferability such attack evaluations under the fail adversary model may also suggest promising directions for future defenses
|
[['recent', 'results', 'suggest', 'that', 'attacks', 'against', 'supervised', 'machine', 'learning', 'systems', 'are', 'quite', 'effective', 'while', 'defenses', 'are', 'easily', 'bypassed', 'by', 'new', 'attacks', 'however', 'the', 'specifications', 'for', 'machine', 'learning', 'systems', 'currently', 'lack', 'precise', 'adversary', 'definitions', 'and', 'the', 'existing', 'attacks', 'make', 'diverse', 'potentially', 'unrealistic', 'assumptions', 'about', 'the', 'strength', 'of', 'the', 'adversary', 'who', 'launches', 'them', 'we', 'propose', 'the', 'fail', 'attacker', 'model', 'which', 'describes', 'the', 'adversarys', 'knowledge', 'and', 'control', 'along', 'four', 'dimensions', 'our', 'model', 'allows', 'us', 'to', 'consider', 'a', 'wide', 'range', 'of', 'weaker', 'adversaries', 'who', 'have', 'limited', 'control', 'and', 'incomplete', 'knowledge', 'of', 'the', 'features', 'learning', 'algorithms', 'and', 'training', 'instances', 'utilized', 'to', 'evaluate', 'the', 'utility', 'of', 'the', 'fail', 'model', 'we', 'consider', 'the', 'problem', 'of', 'conducting', 'targeted', 'poisoning', 'attacks', 'in', 'a', 'realistic', 'setting', 'the', 'crafted', 'poison', 'samples', 'must', 'have', 'clean', 'labels', 'must', 'be', 'individually', 'and', 'collectively', 'inconspicuous', 'and', 'must', 'exhibit', 'a', 'generalized', 'form', 'of', 'transferability', 'defined', 'by', 'the', 'fail', 'model', 'by', 'taking', 'these', 'constraints', 'into', 'account', 'we', 'design', 'stingray', 'a', 'targeted', 'poisoning', 'attack', 'that', 'is', 'practical', 'against', '4', 'machine', 'learning', 'applications', 'which', 'use', '3', 'different', 'learning', 'algorithms', 'and', 'can', 'bypass', '2', 'existing', 'defenses', 'conversely', 'we', 'show', 'that', 'a', 'prior', 'evasion', 'attack', 'is', 'less', 'effective', 'under', 'generalized', 'transferability', 'such', 'attack', 'evaluations', 'under', 'the', 'fail', 'adversary', 'model', 'may', 'also', 'suggest', 'promising', 'directions', 'for', 'future', 'defenses']]
|
[-0.10540127640282645, 0.023302192872224004, -0.0690915993340223, 0.12769267722275968, -0.13064506147237656, -0.2947901354885651, 0.09692752098176376, 0.38836975819295616, -0.242327079251499, -0.3479094540325075, 0.10905169328229357, -0.2621481483723789, -0.16794531652025735, 0.2030812775556821, -0.15435546717054924, 0.10423454680272097, 0.052053474788373175, -0.005911483730017705, -0.01743551344244551, -0.3245501653539939, 0.33608129412741355, 0.03070363637344749, 0.31197013858721584, 0.019718097727994426, 0.050497951035758534, 0.010896471865052465, 0.015351719339236897, 0.01843110872318152, -0.07781837365258168, 0.10887320981828894, 0.32979366095446716, 0.21414810037963744, 0.3532671681899143, -0.44612970595582596, -0.2626410395955866, 0.12265412477116344, 0.11800251230687915, 0.17412148520250995, -0.03766822487565698, -0.346932203373284, 0.12338335105885968, -0.22433444556612883, -0.04882754936805266, -0.17312895447395524, -0.04654836630249776, 0.009914535162484419, -0.274656858096279, -0.04044669193295633, 0.09342976628850187, 0.043397634131359206, -0.046009099665629105, -0.107837348864459, 0.045937242276301984, 0.14390559535134795, 0.05966095143343657, -0.02493178278255249, 0.2195950982068186, -0.1519094735179625, -0.14468070800479466, 0.3399837313907094, -0.0001762662245665939, -0.18311260414310648, 0.21993571472833456, 0.01627530400568927, -0.1517903206562533, 0.10788072160110601, 0.23179253848756717, 0.11613079256748834, -0.16072690222034847, 0.030711342869676847, -0.018282209737768885, 0.1729731222301568, 0.018877060056519377, 0.014011876598832388, 0.1779613820022171, 0.16528921742534752, 0.08132095801083425, 0.12078842358014917, -0.08372047909372148, -0.06700653463457394, -0.23165559027235486, -0.06205148330451107, -0.1395099070036187, 0.034749573706965714, -0.0576587258109815, -0.09184843721546378, 0.3426761434388627, 0.27285641632144547, 0.1731749848028627, 0.08892772610647405, 0.3746596716470944, -0.007426069119777892, 0.11924379280185128, 0.13725022051496955, 0.23882107648465023, -0.0074479957936259295, 0.06815165910729687, -0.1298474533634839, 0.20205254359645497, -0.042131349419523935]
|
1,803.06976
|
Slope limiting the velocity field in a discontinuous Galerkin divergence
free two-phase flow solver
|
Solving the Navier-Stokes equations when the density field contains a large
sharp discontinuity---such as a water/air free surface---is numerically
challenging. Convective instabilities cause Gibbs oscillations which quickly
destroy the solution. We investigate the use of slope limiters for the velocity
field to overcome this problem in a way that does not compromise on the mass
conservation properties. The equations are discretised using the interior
penalty discontinuous Galerkin finite element method that is divergence free to
machine precision.
A slope limiter made specifically for exactly divergence free (solenoidal)
fields is presented and used to illustrated the difficulties in obtaining
convectively stable fields that are also exactly solenoidal. The lessons
learned from this are applied in constructing a simpler method based on the use
of an existing scalar slope limiter applied to each velocity component.
We show by numerical examples how both presented slope limiting methods are
vastly superior to the naive non-limited method. The methods can solve
difficult two-phase problems with high density ratios and high Reynolds
numbers---typical for marine and offshore water/air simulations---in a way that
conserves mass and stops unbounded energy growth caused by the Gibbs
phenomenon.
|
physics.flu-dyn physics.comp-ph
|
solving the navierstokes equations when the density field contains a large sharp discontinuitysuch as a waterair free surfaceis numerically challenging convective instabilities cause gibbs oscillations which quickly destroy the solution we investigate the use of slope limiters for the velocity field to overcome this problem in a way that does not compromise on the mass conservation properties the equations are discretised using the interior penalty discontinuous galerkin finite element method that is divergence free to machine precision a slope limiter made specifically for exactly divergence free solenoidal fields is presented and used to illustrated the difficulties in obtaining convectively stable fields that are also exactly solenoidal the lessons learned from this are applied in constructing a simpler method based on the use of an existing scalar slope limiter applied to each velocity component we show by numerical examples how both presented slope limiting methods are vastly superior to the naive nonlimited method the methods can solve difficult twophase problems with high density ratios and high reynolds numberstypical for marine and offshore waterair simulationsin a way that conserves mass and stops unbounded energy growth caused by the gibbs phenomenon
|
[['solving', 'the', 'navierstokes', 'equations', 'when', 'the', 'density', 'field', 'contains', 'a', 'large', 'sharp', 'discontinuitysuch', 'as', 'a', 'waterair', 'free', 'surfaceis', 'numerically', 'challenging', 'convective', 'instabilities', 'cause', 'gibbs', 'oscillations', 'which', 'quickly', 'destroy', 'the', 'solution', 'we', 'investigate', 'the', 'use', 'of', 'slope', 'limiters', 'for', 'the', 'velocity', 'field', 'to', 'overcome', 'this', 'problem', 'in', 'a', 'way', 'that', 'does', 'not', 'compromise', 'on', 'the', 'mass', 'conservation', 'properties', 'the', 'equations', 'are', 'discretised', 'using', 'the', 'interior', 'penalty', 'discontinuous', 'galerkin', 'finite', 'element', 'method', 'that', 'is', 'divergence', 'free', 'to', 'machine', 'precision', 'a', 'slope', 'limiter', 'made', 'specifically', 'for', 'exactly', 'divergence', 'free', 'solenoidal', 'fields', 'is', 'presented', 'and', 'used', 'to', 'illustrated', 'the', 'difficulties', 'in', 'obtaining', 'convectively', 'stable', 'fields', 'that', 'are', 'also', 'exactly', 'solenoidal', 'the', 'lessons', 'learned', 'from', 'this', 'are', 'applied', 'in', 'constructing', 'a', 'simpler', 'method', 'based', 'on', 'the', 'use', 'of', 'an', 'existing', 'scalar', 'slope', 'limiter', 'applied', 'to', 'each', 'velocity', 'component', 'we', 'show', 'by', 'numerical', 'examples', 'how', 'both', 'presented', 'slope', 'limiting', 'methods', 'are', 'vastly', 'superior', 'to', 'the', 'naive', 'nonlimited', 'method', 'the', 'methods', 'can', 'solve', 'difficult', 'twophase', 'problems', 'with', 'high', 'density', 'ratios', 'and', 'high', 'reynolds', 'numberstypical', 'for', 'marine', 'and', 'offshore', 'waterair', 'simulationsin', 'a', 'way', 'that', 'conserves', 'mass', 'and', 'stops', 'unbounded', 'energy', 'growth', 'caused', 'by', 'the', 'gibbs', 'phenomenon']]
|
[-0.08239131662412547, 0.13351220560411015, -0.11053452650388784, 0.09390607423088311, -0.10202037810813636, -0.13583909314247253, -0.00819125733561004, 0.35161207501179254, -0.2817808533816234, -0.29006625687527604, 0.1041935956852641, -0.23511318964681224, -0.09878053490335689, 0.21216876432046536, -0.09278238908407967, 0.1063901383034966, 0.08108046493346235, -0.025376119468685076, -0.0738088836002609, -0.21617376922538667, 0.30533636360854394, 0.03427761789925685, 0.31527675361291546, 0.04092598105806088, 0.1363967865042429, -0.07714149981114568, 0.014668644555216737, 0.07135125223051189, -0.15198365097216004, 0.0755348944797373, 0.2404841090813178, 0.06089652210737214, 0.3073929890904211, -0.42623002841339813, -0.2400860231377326, 0.0965771694748622, 0.16492052689579356, 0.09936657300125301, -0.09106102964268876, -0.21420993502618765, 0.09153904044702042, -0.1559171368084524, -0.18720097109073083, -0.10068184968575065, -0.038534920684153054, 0.03869618948342775, -0.2763947077910416, 0.12995217254992103, 0.023072454317867676, 0.04949737979230755, -0.0732231695899669, -0.11712702104705386, -0.04505105971475132, 0.06424616477101075, 0.07973386181908174, 0.007714166932324271, 0.13000800406671656, -0.1445361745716819, -0.04358774081059812, 0.36929459026862826, -0.07717882787413977, -0.26977343744692917, 0.1997715445632702, -0.08939212679346699, -0.0872863773130002, 0.1714168641103796, 0.16651818305051522, 0.13878621346236247, -0.1253574066584248, 0.07059853706817629, 0.006578166607220698, 0.16549673953862942, 0.06771068093771844, -0.08885662092665292, 0.15869635772516788, 0.12579094045972655, 0.11889633387529655, 0.10523110713161853, -0.09226264145842794, -0.09875819721618546, -0.30919167878227716, -0.11410764190267124, -0.18541867861463485, -0.009525136588031866, -0.07683469895646736, -0.19651143652204747, 0.3535205329219183, 0.18419478745225049, 0.14492208798638667, 0.048113525296566484, 0.3456358583137879, 0.15781903735320235, 0.07381001558393979, 0.1374137096825744, 0.2273042587786103, 0.16723844451379313, 0.13029491469648707, -0.25656055619196116, 0.024068360629114424, 0.1180545176156675]
|
1,803.06977
|
Exploiting Hopsets: Improved Distance Oracles for Graphs of Constant
Highway Dimension and Beyond
|
For fixed $h \geq 2$, we consider the task of adding to a graph $G$ a set of
weighted shortcut edges on the same vertex set, such that the length of a
shortest $h$-hop path between any pair of vertices in the augmented graph is
exactly the same as the original distance between these vertices in $G$. A set
of shortcut edges with this property is called an exact $h$-hopset and may be
applied in processing distance queries on graph $G$. In particular, a
$2$-hopset directly corresponds to a distributed distance oracle known as a hub
labeling. In this work, we explore centralized distance oracles based on
$3$-hopsets and display their advantages in several practical scenarios. In
particular, for graphs of constant highway dimension, and more generally for
graphs of constant skeleton dimension, we show that $3$-hopsets require
exponentially fewer shortcuts per node than any previously described distance
oracle while incurring only a quadratic increase in the query decoding time,
and actually offer a speedup when compared to simple oracles based on a direct
application of $2$-hopsets. Finally, we consider the problem of computing
minimum-size $h$-hopset (for any $h \geq 2$) for a given graph $G$, showing a
polylogarithmic-factor approximation for the case of unique shortest path
graphs. When $h=3$, for a given bound on the space used by the distance oracle,
we provide a construction of hopsets achieving polylog approximation both for
space and query time compared to the optimal $3$-hopset oracle given the space
bound.
|
cs.DS
|
for fixed h geq 2 we consider the task of adding to a graph g a set of weighted shortcut edges on the same vertex set such that the length of a shortest hhop path between any pair of vertices in the augmented graph is exactly the same as the original distance between these vertices in g a set of shortcut edges with this property is called an exact hhopset and may be applied in processing distance queries on graph g in particular a 2hopset directly corresponds to a distributed distance oracle known as a hub labeling in this work we explore centralized distance oracles based on 3hopsets and display their advantages in several practical scenarios in particular for graphs of constant highway dimension and more generally for graphs of constant skeleton dimension we show that 3hopsets require exponentially fewer shortcuts per node than any previously described distance oracle while incurring only a quadratic increase in the query decoding time and actually offer a speedup when compared to simple oracles based on a direct application of 2hopsets finally we consider the problem of computing minimumsize hhopset for any h geq 2 for a given graph g showing a polylogarithmicfactor approximation for the case of unique shortest path graphs when h3 for a given bound on the space used by the distance oracle we provide a construction of hopsets achieving polylog approximation both for space and query time compared to the optimal 3hopset oracle given the space bound
|
[['for', 'fixed', 'h', 'geq', '2', 'we', 'consider', 'the', 'task', 'of', 'adding', 'to', 'a', 'graph', 'g', 'a', 'set', 'of', 'weighted', 'shortcut', 'edges', 'on', 'the', 'same', 'vertex', 'set', 'such', 'that', 'the', 'length', 'of', 'a', 'shortest', 'hhop', 'path', 'between', 'any', 'pair', 'of', 'vertices', 'in', 'the', 'augmented', 'graph', 'is', 'exactly', 'the', 'same', 'as', 'the', 'original', 'distance', 'between', 'these', 'vertices', 'in', 'g', 'a', 'set', 'of', 'shortcut', 'edges', 'with', 'this', 'property', 'is', 'called', 'an', 'exact', 'hhopset', 'and', 'may', 'be', 'applied', 'in', 'processing', 'distance', 'queries', 'on', 'graph', 'g', 'in', 'particular', 'a', '2hopset', 'directly', 'corresponds', 'to', 'a', 'distributed', 'distance', 'oracle', 'known', 'as', 'a', 'hub', 'labeling', 'in', 'this', 'work', 'we', 'explore', 'centralized', 'distance', 'oracles', 'based', 'on', '3hopsets', 'and', 'display', 'their', 'advantages', 'in', 'several', 'practical', 'scenarios', 'in', 'particular', 'for', 'graphs', 'of', 'constant', 'highway', 'dimension', 'and', 'more', 'generally', 'for', 'graphs', 'of', 'constant', 'skeleton', 'dimension', 'we', 'show', 'that', '3hopsets', 'require', 'exponentially', 'fewer', 'shortcuts', 'per', 'node', 'than', 'any', 'previously', 'described', 'distance', 'oracle', 'while', 'incurring', 'only', 'a', 'quadratic', 'increase', 'in', 'the', 'query', 'decoding', 'time', 'and', 'actually', 'offer', 'a', 'speedup', 'when', 'compared', 'to', 'simple', 'oracles', 'based', 'on', 'a', 'direct', 'application', 'of', '2hopsets', 'finally', 'we', 'consider', 'the', 'problem', 'of', 'computing', 'minimumsize', 'hhopset', 'for', 'any', 'h', 'geq', '2', 'for', 'a', 'given', 'graph', 'g', 'showing', 'a', 'polylogarithmicfactor', 'approximation', 'for', 'the', 'case', 'of', 'unique', 'shortest', 'path', 'graphs', 'when', 'h3', 'for', 'a', 'given', 'bound', 'on', 'the', 'space', 'used', 'by', 'the', 'distance', 'oracle', 'we', 'provide', 'a', 'construction', 'of', 'hopsets', 'achieving', 'polylog', 'approximation', 'both', 'for', 'space', 'and', 'query', 'time', 'compared', 'to', 'the', 'optimal', '3hopset', 'oracle', 'given', 'the', 'space', 'bound']]
|
[-0.1464060678713756, 0.053250183611019575, -0.028197506855721255, 0.06435818353445741, -0.08893194142144532, -0.17014061804533503, 0.1258403411326018, 0.4203479262263705, -0.2803945150988656, -0.3328792251856943, 0.06170093561751597, -0.27655633013290215, -0.12589341381401073, 0.18648519566493055, -0.08403432931295336, 0.05568936409498857, 0.10589797920488975, 0.12477929080277779, -0.05188849830423252, -0.27621233128215805, 0.2804980611756919, 0.0041141626658892285, 0.18700543091979235, 0.0409578640967662, 0.11203674100403709, 0.040452832800324495, 0.01593841454325922, 0.07304355944178036, -0.1313867166304837, 0.12270181673962748, 0.23367832650461676, 0.16769890484856012, 0.28557253890830603, -0.4045860537030212, -0.18060278778817312, 0.1842286074714283, 0.14080710536079427, 0.08505870422317206, -0.00800171471133908, -0.2394853448110465, 0.10974206717414041, -0.11018122032588683, -0.05638245685088398, 0.004194284566175426, 0.10470197962550251, -0.0016461450703516135, -0.30674632055739476, -0.011063539117153843, 0.06455208255352149, 0.02612799124901327, 0.024655967203619653, -0.1132831879186144, 0.03283938170395106, 0.11810752595156221, -0.05071349310197684, 0.12093894822897086, 0.055125000032013725, -0.11242793708509731, -0.1839187311677839, 0.37884566205004266, -0.05366435644727553, -0.19194514191004147, 0.1478082586331176, -0.07719724000603054, -0.13672374705218995, 0.08846804145606679, 0.18003178474388112, 0.14171271567197835, -0.10777787376347653, 0.12556886468665351, -0.06489609913300395, 0.15173638250024124, 0.11709582599105944, 0.053379637972942734, 0.08558336713052478, 0.15914960158477384, 0.19359800586219736, 0.16932228820108142, -0.03335476021679843, -0.03451125464250166, -0.30996956641563683, -0.16521959728573518, -0.26536036784678824, 0.03366851955642495, -0.20606123759401776, -0.18522284394344432, 0.3748339688479433, 0.13260786246681766, 0.24786675570407984, 0.15451414348503037, 0.2686232397854952, 0.07208171149122258, 0.06613259154998319, 0.20103439272607376, 0.15177020496419907, 0.06497937603512678, -0.003927199367753319, -0.16659185590970654, 0.08281837047416732, 0.11545390221114937]
|
1,803.06978
|
Improving Transferability of Adversarial Examples with Input Diversity
|
Though CNNs have achieved the state-of-the-art performance on various vision
tasks, they are vulnerable to adversarial examples --- crafted by adding
human-imperceptible perturbations to clean images. However, most of the
existing adversarial attacks only achieve relatively low success rates under
the challenging black-box setting, where the attackers have no knowledge of the
model structure and parameters. To this end, we propose to improve the
transferability of adversarial examples by creating diverse input patterns.
Instead of only using the original images to generate adversarial examples, our
method applies random transformations to the input images at each iteration.
Extensive experiments on ImageNet show that the proposed attack method can
generate adversarial examples that transfer much better to different networks
than existing baselines. By evaluating our method against top defense solutions
and official baselines from NIPS 2017 adversarial competition, the enhanced
attack reaches an average success rate of 73.0%, which outperforms the top-1
attack submission in the NIPS competition by a large margin of 6.6%. We hope
that our proposed attack strategy can serve as a strong benchmark baseline for
evaluating the robustness of networks to adversaries and the effectiveness of
different defense methods in the future. Code is available at
https://github.com/cihangxie/DI-2-FGSM.
|
cs.CV cs.LG stat.ML
|
though cnns have achieved the stateoftheart performance on various vision tasks they are vulnerable to adversarial examples crafted by adding humanimperceptible perturbations to clean images however most of the existing adversarial attacks only achieve relatively low success rates under the challenging blackbox setting where the attackers have no knowledge of the model structure and parameters to this end we propose to improve the transferability of adversarial examples by creating diverse input patterns instead of only using the original images to generate adversarial examples our method applies random transformations to the input images at each iteration extensive experiments on imagenet show that the proposed attack method can generate adversarial examples that transfer much better to different networks than existing baselines by evaluating our method against top defense solutions and official baselines from nips 2017 adversarial competition the enhanced attack reaches an average success rate of 730 which outperforms the top1 attack submission in the nips competition by a large margin of 66 we hope that our proposed attack strategy can serve as a strong benchmark baseline for evaluating the robustness of networks to adversaries and the effectiveness of different defense methods in the future code is available at httpsgithubcomcihangxiedi2fgsm
|
[['though', 'cnns', 'have', 'achieved', 'the', 'stateoftheart', 'performance', 'on', 'various', 'vision', 'tasks', 'they', 'are', 'vulnerable', 'to', 'adversarial', 'examples', 'crafted', 'by', 'adding', 'humanimperceptible', 'perturbations', 'to', 'clean', 'images', 'however', 'most', 'of', 'the', 'existing', 'adversarial', 'attacks', 'only', 'achieve', 'relatively', 'low', 'success', 'rates', 'under', 'the', 'challenging', 'blackbox', 'setting', 'where', 'the', 'attackers', 'have', 'no', 'knowledge', 'of', 'the', 'model', 'structure', 'and', 'parameters', 'to', 'this', 'end', 'we', 'propose', 'to', 'improve', 'the', 'transferability', 'of', 'adversarial', 'examples', 'by', 'creating', 'diverse', 'input', 'patterns', 'instead', 'of', 'only', 'using', 'the', 'original', 'images', 'to', 'generate', 'adversarial', 'examples', 'our', 'method', 'applies', 'random', 'transformations', 'to', 'the', 'input', 'images', 'at', 'each', 'iteration', 'extensive', 'experiments', 'on', 'imagenet', 'show', 'that', 'the', 'proposed', 'attack', 'method', 'can', 'generate', 'adversarial', 'examples', 'that', 'transfer', 'much', 'better', 'to', 'different', 'networks', 'than', 'existing', 'baselines', 'by', 'evaluating', 'our', 'method', 'against', 'top', 'defense', 'solutions', 'and', 'official', 'baselines', 'from', 'nips', '2017', 'adversarial', 'competition', 'the', 'enhanced', 'attack', 'reaches', 'an', 'average', 'success', 'rate', 'of', '730', 'which', 'outperforms', 'the', 'top1', 'attack', 'submission', 'in', 'the', 'nips', 'competition', 'by', 'a', 'large', 'margin', 'of', '66', 'we', 'hope', 'that', 'our', 'proposed', 'attack', 'strategy', 'can', 'serve', 'as', 'a', 'strong', 'benchmark', 'baseline', 'for', 'evaluating', 'the', 'robustness', 'of', 'networks', 'to', 'adversaries', 'and', 'the', 'effectiveness', 'of', 'different', 'defense', 'methods', 'in', 'the', 'future', 'code', 'is', 'available', 'at', 'httpsgithubcomcihangxiedi2fgsm']]
|
[-0.055582058347695446, -0.016591929941042798, -0.019665830077244168, 0.08974472018370055, -0.06795264140059841, -0.22611677703840025, 0.06992916465940209, 0.40627037694791174, -0.20783427566453003, -0.38014784122717943, 0.081556486171126, -0.3049438050168042, -0.19133992717119153, 0.23722835994966157, -0.1605041598768782, 0.10329700747639566, 0.12509843186111316, 0.010717874717293543, -0.040709119246974776, -0.3953082781582882, 0.3058195208012585, 0.09156866328492949, 0.36771233250306645, 0.030239369659649143, 0.10208259617465401, -0.08027608044413603, 0.008478538270745435, -0.014038289098191988, -0.028887581814552935, 0.11446457943136847, 0.31322614681163297, 0.20902364119192407, 0.340603682497365, -0.398964488302088, -0.222832964573689, 0.07840696375977796, 0.0849850525037116, 0.17023446520277521, -0.0668271252693996, -0.39218743419780533, 0.1464809417540827, -0.2077494660406586, 0.012213197820418074, -0.1614871654248215, -0.033306906662224245, 0.005788005717680199, -0.29348793661672157, -0.007961292623970386, 0.08582237118034892, 0.060652470539990566, -0.007591906834516655, -0.1227807913041735, -0.020129705167039852, 0.16180710374675503, 0.06313280029657302, 0.049095864698461014, 0.16445149718381957, -0.1834262019492506, -0.16864597238482065, 0.3392945918098546, -0.09128773808315323, -0.18817772515090644, 0.22451334111723426, 0.01860195785278672, -0.1062497282353452, 0.12377187607072407, 0.26106606134308646, 0.14904779557441242, -0.10173618268761736, -0.011412853473912084, -0.03362209291031453, 0.18451737755257164, 0.08551211496885998, -0.008182442868199332, 0.10661885850627902, 0.21452419482364182, 0.06102419116293189, 0.16238814633018173, -0.13487120003671135, -0.08148688071958135, -0.21615166984838882, -0.022963292407448672, -0.2042719653812308, -0.005204288514690275, -0.09054027593005885, -0.08757689968224255, 0.4217842999670825, 0.28727230355190825, 0.1924045664461585, 0.11361961523224576, 0.38853491185620653, -0.032799107267232945, 0.11243427764869007, 0.1109660133562254, 0.24504732379812727, -0.041346162284291846, 0.07794297444468676, -0.15757908909416138, 0.15365641493808838, 0.01589097545912423]
|
1,803.06979
|
Non-Abelian two-form gauge transformation and gauge theories in six
dimensions
|
A new non-Abelian gauge transformation for two-forms is introduced.
Construction is based on a fixed map from the spacetime to the loop space which
attachs a closed loop to each point of the spacetime. It is argued that this
set-up is consistent with the surface ordering ambiguity which is the main
problem to construct the Wilson surface operator for non-Abelian groups. With
the aim of the Wilson surface operator, we achieve a non-Abelian gauge
transformation for two-forms. We interpret the Dirac operator as a vector field
and define a covariant derivative and rederive the gauge transformation of the
two-form. At the end, we construct an Abelian interacting gauge theory in six
dimensions.
|
hep-th
|
a new nonabelian gauge transformation for twoforms is introduced construction is based on a fixed map from the spacetime to the loop space which attachs a closed loop to each point of the spacetime it is argued that this setup is consistent with the surface ordering ambiguity which is the main problem to construct the wilson surface operator for nonabelian groups with the aim of the wilson surface operator we achieve a nonabelian gauge transformation for twoforms we interpret the dirac operator as a vector field and define a covariant derivative and rederive the gauge transformation of the twoform at the end we construct an abelian interacting gauge theory in six dimensions
|
[['a', 'new', 'nonabelian', 'gauge', 'transformation', 'for', 'twoforms', 'is', 'introduced', 'construction', 'is', 'based', 'on', 'a', 'fixed', 'map', 'from', 'the', 'spacetime', 'to', 'the', 'loop', 'space', 'which', 'attachs', 'a', 'closed', 'loop', 'to', 'each', 'point', 'of', 'the', 'spacetime', 'it', 'is', 'argued', 'that', 'this', 'setup', 'is', 'consistent', 'with', 'the', 'surface', 'ordering', 'ambiguity', 'which', 'is', 'the', 'main', 'problem', 'to', 'construct', 'the', 'wilson', 'surface', 'operator', 'for', 'nonabelian', 'groups', 'with', 'the', 'aim', 'of', 'the', 'wilson', 'surface', 'operator', 'we', 'achieve', 'a', 'nonabelian', 'gauge', 'transformation', 'for', 'twoforms', 'we', 'interpret', 'the', 'dirac', 'operator', 'as', 'a', 'vector', 'field', 'and', 'define', 'a', 'covariant', 'derivative', 'and', 'rederive', 'the', 'gauge', 'transformation', 'of', 'the', 'twoform', 'at', 'the', 'end', 'we', 'construct', 'an', 'abelian', 'interacting', 'gauge', 'theory', 'in', 'six', 'dimensions']]
|
[-0.15890221434922233, 0.1872333262446347, -0.12005719901503038, 0.08715747643748785, -0.13407813767936114, -0.1343473932718405, 0.005466680087543487, 0.3440727153373463, -0.2045330627913679, -0.23390426575667686, 0.07552113786637615, -0.23434799096572237, -0.19411286251904727, 0.10609971260366675, -0.07362346784085841, -0.0023263538264677868, -0.019915620553063916, 0.11375663856564609, -0.1343001598987292, -0.24283359342397334, 0.400199299522986, 0.004841641596359041, 0.27248845490215867, 0.024752235161727882, 0.1773505519051944, 0.001056157967058925, -0.03986712864092509, -0.013384874570571506, -0.06979253618834542, 0.11435311827661788, 0.19160832343035722, 0.027129090042902274, 0.14633655620252226, -0.3570813110249268, -0.22395465599120226, 0.08579153573845287, 0.10888816179657304, 0.11473199649428663, -0.019732189923734614, -0.2978618715696775, 0.05805285416778412, -0.15681068942387094, -0.17318597853368334, -0.08388474837851685, 0.002273473356900787, -0.12707694406780573, -0.2825009315316607, 0.0056515939700270915, 0.0037274777150905886, 0.0651629207957838, -0.06837259926875164, -0.04200246288264926, -0.05610375966759281, 0.08800640718189177, 0.0725043010457444, 0.13883963692513807, 0.10006834560719964, -0.12014202432715343, -0.1409779723968592, 0.40337348184002947, -0.10396991860381588, -0.2751863823683412, 0.12831248489191738, -0.13492578011727682, -0.17116310383268707, 0.08800448858520205, 0.10031235254545873, 0.1380603938774617, -0.1489192036165109, 0.19304503317448302, -0.07152755097024613, 0.09832284977236921, 0.07257033268677758, -0.013075139360955439, 0.22655349182015336, 0.07963682012947125, 0.11701715672136964, 0.14900422661128948, -0.01583427653295567, -0.10307844374370803, -0.43088291066925266, -0.2149620588120547, -0.13882729642697283, 0.07233729621244443, -0.09617655209306553, -0.21398614467591517, 0.40009919731869353, 0.1335197517413411, 0.1739175798086164, 0.04770734621765646, 0.2170364924345736, 0.16307632810423603, 0.10279153597851594, 0.0530995534195959, 0.1614955780736112, 0.20820282627031342, 0.04432431551699132, -0.23677576158137, -0.14556282508262508, 0.22428328170323628]
|
1,803.0698
|
Second order ensemble simulation for MHD flow in Els\"asser variable
with noisy input data
|
We propose, analyze and test a fully discrete, efficient second-order
algorithm for computing flow ensembles average of viscous, incompressible, and
time-dependent magnetohydrodynamic (MHD) flows under uncertainties in initial
conditions. The scheme is decoupled and based on Els\"asser variable
formulation. The algorithm uses the breakthrough idea of Jiang and Layton, 2014
to approximate the ensemble average of $J$ realizations. That is, at each time
step, each of the $J$ realization shares the same coefficient matrix for
different right-hand side matrices. Thus, storage requirements and
computational time are reduced by building preconditioners once per time step
and reuse them. We prove stability and optimal convergence with respect to the
time step restriction. On some manufactured solutions, numerical experiments
are given to verify the predicted convergence rates of our analysis. Finally,
we test the scheme on a benchmark channel flow over a step and it performs
well.
|
math.NA
|
we propose analyze and test a fully discrete efficient secondorder algorithm for computing flow ensembles average of viscous incompressible and timedependent magnetohydrodynamic mhd flows under uncertainties in initial conditions the scheme is decoupled and based on elsasser variable formulation the algorithm uses the breakthrough idea of jiang and layton 2014 to approximate the ensemble average of j realizations that is at each time step each of the j realization shares the same coefficient matrix for different righthand side matrices thus storage requirements and computational time are reduced by building preconditioners once per time step and reuse them we prove stability and optimal convergence with respect to the time step restriction on some manufactured solutions numerical experiments are given to verify the predicted convergence rates of our analysis finally we test the scheme on a benchmark channel flow over a step and it performs well
|
[['we', 'propose', 'analyze', 'and', 'test', 'a', 'fully', 'discrete', 'efficient', 'secondorder', 'algorithm', 'for', 'computing', 'flow', 'ensembles', 'average', 'of', 'viscous', 'incompressible', 'and', 'timedependent', 'magnetohydrodynamic', 'mhd', 'flows', 'under', 'uncertainties', 'in', 'initial', 'conditions', 'the', 'scheme', 'is', 'decoupled', 'and', 'based', 'on', 'elsasser', 'variable', 'formulation', 'the', 'algorithm', 'uses', 'the', 'breakthrough', 'idea', 'of', 'jiang', 'and', 'layton', '2014', 'to', 'approximate', 'the', 'ensemble', 'average', 'of', 'j', 'realizations', 'that', 'is', 'at', 'each', 'time', 'step', 'each', 'of', 'the', 'j', 'realization', 'shares', 'the', 'same', 'coefficient', 'matrix', 'for', 'different', 'righthand', 'side', 'matrices', 'thus', 'storage', 'requirements', 'and', 'computational', 'time', 'are', 'reduced', 'by', 'building', 'preconditioners', 'once', 'per', 'time', 'step', 'and', 'reuse', 'them', 'we', 'prove', 'stability', 'and', 'optimal', 'convergence', 'with', 'respect', 'to', 'the', 'time', 'step', 'restriction', 'on', 'some', 'manufactured', 'solutions', 'numerical', 'experiments', 'are', 'given', 'to', 'verify', 'the', 'predicted', 'convergence', 'rates', 'of', 'our', 'analysis', 'finally', 'we', 'test', 'the', 'scheme', 'on', 'a', 'benchmark', 'channel', 'flow', 'over', 'a', 'step', 'and', 'it', 'performs', 'well']]
|
[-0.12223171783689331, 0.04814387096899685, -0.09123621525249437, -0.001144867978169472, -0.037511387164216044, -0.17422375528115805, 0.045890801270342584, 0.38276891784182376, -0.26872569123133233, -0.2982515875869626, 0.1547985632563583, -0.227864635372339, -0.09434645121812925, 0.19707364519289533, -0.03785573851506037, 0.15624703949486668, 0.10126484736150547, -0.025475073657877795, -0.08361990055414503, -0.29592711238477093, 0.26063613864508545, 0.09093060630041506, 0.31285530159948394, -0.002611228908408902, 0.1468141327019442, -0.037200119423719084, -0.07916324928083776, 0.007332207811703267, -0.13016795901642905, 0.08106146430616247, 0.2194501540812475, 0.09502584795415453, 0.3024417796803938, -0.44467264764626363, -0.18200069818307052, 0.04786297674714164, 0.11393209899143948, 0.11879176299992975, -0.020422860264445987, -0.23137896007962422, 0.11058144036589282, -0.14259591154669496, -0.10435132597983404, -0.08369696605136501, 0.010662619552047519, 0.04073146906831152, -0.3458754156384018, 0.08499421672797859, 0.04293117696383538, 0.021739007169185403, -0.06396447964520617, -0.11633544811698888, 0.008774549534244763, 0.10215293207707313, 0.03240727195011491, -0.0036112940837661704, 0.11606946020628085, -0.07679170462582911, -0.11179598240129701, 0.3810874967790254, -0.0628805229122021, -0.23852013556573254, 0.17790451161832047, -0.08279952838352614, -0.11888350981411401, 0.10392712358665372, 0.20103272297777808, 0.14089150705954412, -0.08726172575440544, 0.057561296054611466, -0.05722289940772148, 0.15530222808857533, 0.061189648781583963, -0.007116227244658695, 0.10814273907067058, 0.16866546990415016, 0.12076186426830562, 0.12298400897362352, -0.07147265609687152, -0.14016984527526827, -0.3174730447622446, -0.16770684729506086, -0.19978706167450735, 0.008310826351195313, -0.1155397583286024, -0.10096944236341449, 0.39141463732095133, 0.1599607399723434, 0.17138678502695232, 0.1043422215494451, 0.3263274707206219, 0.13793154178802705, 0.004737034759165107, 0.1626464677942018, 0.17079836992857086, 0.1311879267450422, 0.11962944809005473, -0.24528508372865357, 0.0649009648428813, 0.1496111652195141]
|
1,803.06981
|
Quantitative weighted estimates for the Littlewood-Paley square function
and Marcinkiewicz multipliers
|
Quantitative weighted estimates are obtained for the Littlewood-Paley square
function $S$ associated with a lacunary decomposition of ${\mathbb R}$ and for
the Marcinkiewicz multiplier operator. In particular, we find the sharp
dependence on $[w]_{A_p}$ for the $L^p(w)$ operator norm of $S$ for $1<p\le 2$.
|
math.CA
|
quantitative weighted estimates are obtained for the littlewoodpaley square function s associated with a lacunary decomposition of mathbb r and for the marcinkiewicz multiplier operator in particular we find the sharp dependence on w_a_p for the lpw operator norm of s for 1ple 2
|
[['quantitative', 'weighted', 'estimates', 'are', 'obtained', 'for', 'the', 'littlewoodpaley', 'square', 'function', 's', 'associated', 'with', 'a', 'lacunary', 'decomposition', 'of', 'mathbb', 'r', 'and', 'for', 'the', 'marcinkiewicz', 'multiplier', 'operator', 'in', 'particular', 'we', 'find', 'the', 'sharp', 'dependence', 'on', 'w_a_p', 'for', 'the', 'lpw', 'operator', 'norm', 'of', 's', 'for', '1ple', '2']]
|
[-0.10109358487798917, 0.04618089252405546, -0.031735810605327555, 0.1272998353127729, -0.031067242337898773, -0.11331866951447657, -0.03718324064869772, 0.35152950239452446, -0.31637055380269885, -0.135623628358272, 0.17526363060460426, -0.34940086711536755, -0.07323573072525588, 0.22988625429570675, -0.07859766129827635, 0.08007438450162722, 0.029067604054117426, 0.08064527750353921, -0.16877602419646626, -0.21099163955924186, 0.3442301464859735, -0.040734471107663754, 0.17363734869286418, 0.08599891340550543, 0.05826253041794354, 0.04681386561556296, -0.0643746750746769, -0.064313326200301, -0.25270405832932075, 0.17538562319664794, 0.19134242963892492, 0.07251950262368402, 0.29871299625797704, -0.36444039725359867, -0.12557925008745355, 0.18652196900538084, 0.13817883989196905, -0.14785003526644272, -0.04131494256382046, -0.2611739287491549, 0.08627288028682498, -0.08818647773428397, -0.1477682329476176, -0.08626664815661074, 0.0943077821707861, 0.11015377494252541, -0.4606038124977865, 0.15709930103780193, 0.09821768722031265, 0.11083339794475416, -0.13507185483732345, -0.22249515283196655, 0.007203666874292222, 0.03606752853374928, -0.03592016693966633, 0.10387731157507832, 0.026234711954285474, -0.04724653478479013, -0.05710626512088559, 0.237758023198694, -0.13356460019184108, -0.23699987343173812, 0.05090984793125906, -0.22939270391890948, -0.126597861177288, 0.04309497638182207, 0.0879382804163139, 0.15343011704019524, -0.042936147190630436, 0.2008900304565693, -0.08881215464366092, 0.08345854044256901, 0.08561455309179357, 0.07730433653870766, -0.015010290525176308, 0.05630501261806454, 0.21905340172816068, 0.10835864701287144, -0.05819678166484333, 0.003240793752907352, -0.41709085723215883, -0.17165012176635422, -0.21622113362801346, 0.09017307000150057, -0.1966542380075473, -0.21089318246495994, 0.3720875092866746, 0.01600062294693833, 0.18164742710492152, 0.12866085283034903, 0.12930758873170073, 0.16492552998137067, 0.06333078306422314, 0.040868481155484915, 0.1357955235606906, 0.21489906741242687, 0.07402824082369493, -0.18682029625316235, -0.0215793403966183, 0.2764727810016749]
|
1,803.06982
|
Quantifying coherence with quantum addition
|
Quantum addition channels have been recently introduced in the context of
deriving entropic power inequalities for finite dimensional quantum systems. We
prove a reverse entropy power equality which can be used to analytically prove
an inequality conjectured recently for arbitrary dimension and arbitrary
addition weight. We show that the relative entropic difference between the
output of such a quantum additon channel and the corresponding classical
mixture quantitatively captures the amount of coherence present in a quantum
system. This new coherence measure admits an upper bound in terms of the
relative entropy of coherence and is utilized to formulate a state-dependent
uncertainty relation for two observables. Our results may provide deep insights
to the origin of quantum coherence for mixed states that truly come from the
discrepancy between quantum addition and the classical mixture.
|
quant-ph cs.IT math.IT
|
quantum addition channels have been recently introduced in the context of deriving entropic power inequalities for finite dimensional quantum systems we prove a reverse entropy power equality which can be used to analytically prove an inequality conjectured recently for arbitrary dimension and arbitrary addition weight we show that the relative entropic difference between the output of such a quantum additon channel and the corresponding classical mixture quantitatively captures the amount of coherence present in a quantum system this new coherence measure admits an upper bound in terms of the relative entropy of coherence and is utilized to formulate a statedependent uncertainty relation for two observables our results may provide deep insights to the origin of quantum coherence for mixed states that truly come from the discrepancy between quantum addition and the classical mixture
|
[['quantum', 'addition', 'channels', 'have', 'been', 'recently', 'introduced', 'in', 'the', 'context', 'of', 'deriving', 'entropic', 'power', 'inequalities', 'for', 'finite', 'dimensional', 'quantum', 'systems', 'we', 'prove', 'a', 'reverse', 'entropy', 'power', 'equality', 'which', 'can', 'be', 'used', 'to', 'analytically', 'prove', 'an', 'inequality', 'conjectured', 'recently', 'for', 'arbitrary', 'dimension', 'and', 'arbitrary', 'addition', 'weight', 'we', 'show', 'that', 'the', 'relative', 'entropic', 'difference', 'between', 'the', 'output', 'of', 'such', 'a', 'quantum', 'additon', 'channel', 'and', 'the', 'corresponding', 'classical', 'mixture', 'quantitatively', 'captures', 'the', 'amount', 'of', 'coherence', 'present', 'in', 'a', 'quantum', 'system', 'this', 'new', 'coherence', 'measure', 'admits', 'an', 'upper', 'bound', 'in', 'terms', 'of', 'the', 'relative', 'entropy', 'of', 'coherence', 'and', 'is', 'utilized', 'to', 'formulate', 'a', 'statedependent', 'uncertainty', 'relation', 'for', 'two', 'observables', 'our', 'results', 'may', 'provide', 'deep', 'insights', 'to', 'the', 'origin', 'of', 'quantum', 'coherence', 'for', 'mixed', 'states', 'that', 'truly', 'come', 'from', 'the', 'discrepancy', 'between', 'quantum', 'addition', 'and', 'the', 'classical', 'mixture']]
|
[-0.09919965434189242, 0.15206009254347064, -0.12966044220191084, 0.10315321906840891, -0.00042795963739430097, -0.16223970496032694, 0.04233556124731842, 0.3024943220338091, -0.31112259525553626, -0.27168599864173876, 0.04756730984934935, -0.25246932804566996, -0.13567534692697508, 0.2089791436805705, -0.0805804297306988, 0.11229041223659326, 0.02621039224760537, 0.0750116834916346, -0.0713657217320839, -0.24009853247132965, 0.3168069582180421, 0.01661083717367444, 0.3027327141262367, 0.1087170504733808, 0.13244228823726675, -0.006692042766853159, 0.02091781835638939, 0.04398250913674614, -0.16634774482268508, 0.18333796235597938, 0.25344780412383544, 0.12792514675625957, 0.24056566661377823, -0.4081969670111075, -0.2523790129243319, 0.1451586289331317, 0.11033048970918906, 0.12396147506420073, -0.029346229925163482, -0.27593193541427974, 0.054815232752003056, -0.19312025723922857, -0.09480717705380648, -0.09731982385081456, 0.02743734469063076, -0.027787741839087436, -0.2814976803650309, 0.11438227090914559, 0.11069808016879978, 0.03938598317313848, -0.024021343492615716, -0.08155017905199859, 0.054900733923847624, 0.14049523361324845, -0.0326347550843841, -0.008907544706717022, 0.04883163625066329, -0.09805503132460067, -0.17099626054917288, 0.30942151494870396, -0.057339721000438236, -0.20779661901463242, 0.1710289923891712, -0.09129277377256326, -0.10766859808796667, 0.03760031796116522, 0.1664465829008784, 0.06511638288323145, -0.14394331568698013, 0.08949096206246518, -0.044645868066726324, 0.176679567521424, 0.07278578872162204, 0.14585813891870858, 0.17631974199758774, 0.05584465367789555, 0.09506023085424047, 0.23483684114303047, -0.08813117134811084, -0.1729139982454857, -0.3162407553439638, -0.2400226484676928, -0.20206370035578547, 0.08718187635050233, -0.10253255906702138, -0.10716628061985611, 0.3250944736532699, 0.1199219040655797, 0.18920582683084713, 0.07504766972830057, 0.2539917912449744, 0.17937345516122177, 0.019525778074608764, 0.06779458021563023, 0.2494308832381621, 0.20646450468336838, 0.03240366356405325, -0.24636802377172262, 0.08225397729770896, 0.08056174669260706]
|
1,803.06983
|
$QCD_3$ Dualities and the F-Theorem
|
There has recently been a surge of new ideas and results for 2+1 dimensional
gauge theories. We consider a recently proposed duality for 2+1 dimensional
QCD, which predicts a symmetry-breaking phase. Using the F-theorem, we find
bounds on the range of parameters for which the symmetry-breaking phase (and
the corresponding duality) can occur. We find exact bounds for an $ SU(2) $
gauge theory, and approximate bounds for an $SU(N) $ gauge theory with $ N>2 $.
|
hep-th
|
there has recently been a surge of new ideas and results for 21 dimensional gauge theories we consider a recently proposed duality for 21 dimensional qcd which predicts a symmetrybreaking phase using the ftheorem we find bounds on the range of parameters for which the symmetrybreaking phase and the corresponding duality can occur we find exact bounds for an su2 gauge theory and approximate bounds for an sun gauge theory with n2
|
[['there', 'has', 'recently', 'been', 'a', 'surge', 'of', 'new', 'ideas', 'and', 'results', 'for', '21', 'dimensional', 'gauge', 'theories', 'we', 'consider', 'a', 'recently', 'proposed', 'duality', 'for', '21', 'dimensional', 'qcd', 'which', 'predicts', 'a', 'symmetrybreaking', 'phase', 'using', 'the', 'ftheorem', 'we', 'find', 'bounds', 'on', 'the', 'range', 'of', 'parameters', 'for', 'which', 'the', 'symmetrybreaking', 'phase', 'and', 'the', 'corresponding', 'duality', 'can', 'occur', 'we', 'find', 'exact', 'bounds', 'for', 'an', 'su2', 'gauge', 'theory', 'and', 'approximate', 'bounds', 'for', 'an', 'sun', 'gauge', 'theory', 'with', 'n2']]
|
[-0.09237816936284718, 0.1948726895259622, -0.08869856165195718, 0.08081708744996124, -0.044321085682087064, -0.1397495182011173, 0.02945173385281426, 0.32234225577364367, -0.14548906588202548, -0.2984287960765262, 0.12197826577337562, -0.23387901362083438, -0.20867805568397874, 0.15826523141004145, -0.01560173613122768, 0.07089577747198443, -0.040520233583972894, 0.06078517887120446, -0.16318246118155205, -0.24438293096156688, 0.2872436461168238, -0.02732312705160843, 0.27571036633000606, 0.11048031233561535, 0.12211419657493632, -0.005997768538590107, 0.008353801634964637, 0.021299862736163452, -0.19405726699753562, 0.09529036689653164, 0.21439341226424505, 0.07849148524110205, 0.15279104261814305, -0.4191047639275591, -0.2641339977013154, 0.11953581724729803, 0.1301708923775651, 0.19325024778865757, -0.11318882789702103, -0.3140367690551405, 0.07954860499659036, -0.17876021173368725, -0.1378739797882089, -0.10843803269219482, 0.021874207912737295, -0.1068937797487403, -0.3635696314740926, 0.051384323376825906, -0.0007975864767407378, 0.09020929138124403, -0.039061184752629034, -0.09325017035007477, -0.02333278448269185, 0.0690037180061659, 0.10367942431184929, 0.05734370472297693, 0.020817666987164155, -0.16096318506950208, -0.2154939473968827, 0.38081114668036914, -0.06929450238951379, -0.144544897083607, 0.1999373366286616, -0.08362880870441182, -0.2296370597064702, 0.08380044507794082, 0.14514158194005075, 0.12218124085726838, -0.08296359392503898, 0.19888450294335294, -0.10653041352310942, 0.1372377174363161, 0.05537294689565897, 0.037179098956079945, 0.21282198058906943, 0.08987903256072766, 0.07504449156759721, 0.12305366435773774, -0.06509048955114041, -0.16691543912101123, -0.3277460128172404, -0.1285654427079458, -0.11976921386344151, 0.040167668122901685, -0.14390506409048007, -0.11713860108445967, 0.3604175972027911, 0.1441125540667498, 0.17511619827968794, 0.0800831700681657, 0.1814484730510028, 0.1912833763829743, 0.050487946123919554, 0.07095297838612977, 0.2938832510295065, 0.17505703432834707, 0.03929680204924403, -0.18623490549442875, -0.11888377694413066, 0.19803478258998236]
|
1,803.06984
|
Robust Optimization for Electricity Generation
|
We consider a robust optimization problem in an electric power system under
uncertain demand and availability of renewable energy resources. Solving the
deterministic alternating current optimal power flow (ACOPF) problem has been
considered challenging since the 1960s due to its nonconvexity. Linear
approximation of the AC power flow system sees pervasive use, but does not
guarantee a physically feasible system configuration. In recent years, various
convex relaxation schemes for the ACOPF problem have been investigated, and
under some assumptions, a physically feasible solution can be recovered. Based
on these convex relaxations, we construct a robust convex optimization problem
with recourse to solve for optimal controllable injections (fossil fuel,
nuclear, etc.) in electric power systems under uncertainty (renewable energy
generation, demand fluctuation, etc.). We propose a cutting-plane method to
solve this robust optimization problem, and we establish convergence and other
desirable properties. Experimental results indicate that our robust convex
relaxation of the ACOPF problem can provide a tight lower bound.
|
math.OC
|
we consider a robust optimization problem in an electric power system under uncertain demand and availability of renewable energy resources solving the deterministic alternating current optimal power flow acopf problem has been considered challenging since the 1960s due to its nonconvexity linear approximation of the ac power flow system sees pervasive use but does not guarantee a physically feasible system configuration in recent years various convex relaxation schemes for the acopf problem have been investigated and under some assumptions a physically feasible solution can be recovered based on these convex relaxations we construct a robust convex optimization problem with recourse to solve for optimal controllable injections fossil fuel nuclear etc in electric power systems under uncertainty renewable energy generation demand fluctuation etc we propose a cuttingplane method to solve this robust optimization problem and we establish convergence and other desirable properties experimental results indicate that our robust convex relaxation of the acopf problem can provide a tight lower bound
|
[['we', 'consider', 'a', 'robust', 'optimization', 'problem', 'in', 'an', 'electric', 'power', 'system', 'under', 'uncertain', 'demand', 'and', 'availability', 'of', 'renewable', 'energy', 'resources', 'solving', 'the', 'deterministic', 'alternating', 'current', 'optimal', 'power', 'flow', 'acopf', 'problem', 'has', 'been', 'considered', 'challenging', 'since', 'the', '1960s', 'due', 'to', 'its', 'nonconvexity', 'linear', 'approximation', 'of', 'the', 'ac', 'power', 'flow', 'system', 'sees', 'pervasive', 'use', 'but', 'does', 'not', 'guarantee', 'a', 'physically', 'feasible', 'system', 'configuration', 'in', 'recent', 'years', 'various', 'convex', 'relaxation', 'schemes', 'for', 'the', 'acopf', 'problem', 'have', 'been', 'investigated', 'and', 'under', 'some', 'assumptions', 'a', 'physically', 'feasible', 'solution', 'can', 'be', 'recovered', 'based', 'on', 'these', 'convex', 'relaxations', 'we', 'construct', 'a', 'robust', 'convex', 'optimization', 'problem', 'with', 'recourse', 'to', 'solve', 'for', 'optimal', 'controllable', 'injections', 'fossil', 'fuel', 'nuclear', 'etc', 'in', 'electric', 'power', 'systems', 'under', 'uncertainty', 'renewable', 'energy', 'generation', 'demand', 'fluctuation', 'etc', 'we', 'propose', 'a', 'cuttingplane', 'method', 'to', 'solve', 'this', 'robust', 'optimization', 'problem', 'and', 'we', 'establish', 'convergence', 'and', 'other', 'desirable', 'properties', 'experimental', 'results', 'indicate', 'that', 'our', 'robust', 'convex', 'relaxation', 'of', 'the', 'acopf', 'problem', 'can', 'provide', 'a', 'tight', 'lower', 'bound']]
|
[-0.15108912891661455, 0.01687988296303819, -0.06009905622487173, 0.0839439807540251, -0.1121098323133569, -0.19533002612901465, 0.0549932336537226, 0.3938211463596789, -0.3432111855766168, -0.30187670894716895, 0.15395818438758757, -0.2190994909560343, -0.11535993486689697, 0.2360475478318971, -0.14356514365183856, 0.16376204439255837, 0.06305241939002566, -0.038039456827254126, -0.07067967745557474, -0.24580915794933345, 0.22942637296030358, 0.031031729105813137, 0.3410961373061902, 0.0858273818424856, 0.13270034062025962, -0.015314410363013545, 0.037782571225796105, 0.08536702745452043, -0.10428686309101554, 0.1460592958317636, 0.3031587687455727, 0.16842595475239666, 0.35382167196030134, -0.49839964876853443, -0.22490007254154473, 0.14983194884287673, 0.08908808482781568, 0.0805987175085447, -0.10225767441424863, -0.17977651283027804, 0.07916292502345669, -0.17523905426943265, -0.08914430460778398, -0.125660068514382, -0.009110481826787663, 0.02986371980499734, -0.3401219394942453, 0.08008499177533009, 0.043718637178107256, -0.0034621373439828553, -0.13563318780561873, -0.11302794519088483, 0.05472475508266017, 0.0483112547622771, 0.05560543947141477, -0.004555945778148448, 0.13063076201865872, -0.08857574835038926, -0.1240867478875502, 0.3911311835425455, 0.025655183998235274, -0.2347336629721916, 0.13746325758069097, -0.03897406188653981, -0.15954650537720033, 0.1363848590294965, 0.24198433185734278, 0.16215481904903487, -0.20078617827996095, 0.09705560362850954, -0.058347492388364675, 0.1515795197747882, 0.021483703592569573, 0.03724640728495781, 0.1770377027898816, 0.1732736818094111, 0.24507247058106527, 0.17263821861670064, -0.0037777474363855784, -0.11633332491319322, -0.19629369704521396, -0.044715769494131044, -0.1784229548355131, 0.06180078451973902, -0.044869933025135346, -0.12333182046195762, 0.36858830644321516, 0.1437042268320419, 0.10862502914050934, 0.0788009221030036, 0.36441940301150644, 0.18334314178854064, -0.011054831175514316, 0.14286204784780554, 0.2435049843491544, 0.09798157311325788, 0.12304964495761285, -0.27638682246108615, 0.09567333073662769, 0.04420450259492083]
|
1,803.06985
|
The Hessian discretisation method for fourth order linear elliptic
equations
|
In this paper, we propose a unified framework, the Hessian discretisation
method (HDM), which is based on four discrete elements (called altogether a
Hessian discretisation) and a few intrinsic indicators of accuracy, independent
of the considered model. An error estimate is obtained, using only these
intrinsic indicators, when the HDM framework is applied to linear fourth order
problems. It is shown that HDM encompasses a large number of numerical methods
for fourth order elliptic problems: finite element methods (conforming and
non-conforming) as well as finite volume methods. We also use the HDM to design
a novel method, based on conforming $\mathbb{P}_1$ finite element space and
gradient recovery operators. Results of numerical experiments are presented for
this novel scheme and for a finite volume scheme.
|
math.NA
|
in this paper we propose a unified framework the hessian discretisation method hdm which is based on four discrete elements called altogether a hessian discretisation and a few intrinsic indicators of accuracy independent of the considered model an error estimate is obtained using only these intrinsic indicators when the hdm framework is applied to linear fourth order problems it is shown that hdm encompasses a large number of numerical methods for fourth order elliptic problems finite element methods conforming and nonconforming as well as finite volume methods we also use the hdm to design a novel method based on conforming mathbbp_1 finite element space and gradient recovery operators results of numerical experiments are presented for this novel scheme and for a finite volume scheme
|
[['in', 'this', 'paper', 'we', 'propose', 'a', 'unified', 'framework', 'the', 'hessian', 'discretisation', 'method', 'hdm', 'which', 'is', 'based', 'on', 'four', 'discrete', 'elements', 'called', 'altogether', 'a', 'hessian', 'discretisation', 'and', 'a', 'few', 'intrinsic', 'indicators', 'of', 'accuracy', 'independent', 'of', 'the', 'considered', 'model', 'an', 'error', 'estimate', 'is', 'obtained', 'using', 'only', 'these', 'intrinsic', 'indicators', 'when', 'the', 'hdm', 'framework', 'is', 'applied', 'to', 'linear', 'fourth', 'order', 'problems', 'it', 'is', 'shown', 'that', 'hdm', 'encompasses', 'a', 'large', 'number', 'of', 'numerical', 'methods', 'for', 'fourth', 'order', 'elliptic', 'problems', 'finite', 'element', 'methods', 'conforming', 'and', 'nonconforming', 'as', 'well', 'as', 'finite', 'volume', 'methods', 'we', 'also', 'use', 'the', 'hdm', 'to', 'design', 'a', 'novel', 'method', 'based', 'on', 'conforming', 'mathbbp_1', 'finite', 'element', 'space', 'and', 'gradient', 'recovery', 'operators', 'results', 'of', 'numerical', 'experiments', 'are', 'presented', 'for', 'this', 'novel', 'scheme', 'and', 'for', 'a', 'finite', 'volume', 'scheme']]
|
[-0.04688263029487233, 0.03517367007765232, -0.11963209245474107, 0.058466611739863915, -0.0790683057538474, -0.1178545021421967, 0.040021428696608415, 0.3731405034571165, -0.27356283657342917, -0.2579678455292578, 0.14188031431178622, -0.2552675228911422, -0.13622835869459632, 0.2153405381437962, -0.08266480083036568, 0.11148294068181948, 0.06275237426011553, 0.0019049426848669687, -0.1332485441234894, -0.261699685436343, 0.32745584733633987, -0.0031434808136715045, 0.2986441447639898, 0.06287297672186527, 0.16903719360068922, -0.07124923942084875, -0.08518417766167512, 0.07677315160864025, -0.09919873819407873, 0.16820337992882536, 0.25062329289616053, 0.0661871652460949, 0.33121866306229947, -0.3706320612165596, -0.24283588978822432, 0.10022664635682539, 0.12275590992067009, 0.12021227373136958, -0.08770335224765022, -0.23881055284742145, 0.12209188469099783, -0.20879560903525882, -0.11474482458640611, -0.12006140992067935, -0.06579917595691738, 0.026325779469428403, -0.33353055322790637, 0.07974818733407207, 0.027069406964132684, 0.05143670178949833, -0.036736109710839245, -0.15546118480063253, 0.07697763508223297, 0.06494857506726065, 0.009809190718149166, -0.01783916192700065, 0.04048681847615949, -0.0075848256801104835, -0.0846721809958258, 0.4282584428757189, -0.09655882031919676, -0.28678966308343073, 0.1461603488067105, -0.04812964792513559, -0.11088508562252467, 0.10807483106280767, 0.23444552754893178, 0.19357856775769183, -0.12216141035711306, 0.0894084022429231, -0.0315825913003796, 0.18961008971617108, -0.016457526756811044, -0.04307037866824577, 0.07831827263467975, 0.20818268664504191, 0.12801157161893864, 0.06711421532259744, -0.07735910394976306, -0.08554594468836102, -0.38941322920483445, -0.14688535899885238, -0.18789778659195308, -0.0826275569101375, -0.12336173945345029, -0.23062747105605894, 0.3700108070382656, 0.13500542931574128, 0.14011592981255344, 0.04567643210025234, 0.34544231690045807, 0.10844218156172804, 0.06321468148680945, 0.05452789026012103, 0.17277688358069188, 0.1564669704154855, 0.05969828960575884, -0.2085832271991568, 0.034796139473215706, 0.20092820736294192]
|
1,803.06986
|
Search for $\mathrm{t}\overline{\mathrm{t}}$H production in the all-jet
final state in proton-proton collisions at $\sqrt{s}=$ 13 TeV
|
A search is presented for the associated production of a Higgs boson with a
top quark pair in the all-jet final state. Events containing seven or more jets
are selected from a sample of proton-proton collisions at $\sqrt{s} =$ 13 TeV
collected with the CMS detector at the LHC in 2016, corresponding to an
integrated luminosity of 35.9 fb$^{-1}$. To separate the
$\mathrm{t}\overline{\mathrm{t}}$H signal from the irreducible
$\mathrm{t}\overline{\mathrm{t}}+\mathrm{b}\overline{\mathrm{b}}$ background,
the analysis assigns leading order matrix element signal and background
probability densities to each event. A likelihood-ratio statistic based on
these probability densities is used to extract the signal. The results are
provided in terms of an observed $\mathrm{t}\overline{\mathrm{t}}$H signal
strength relative to the standard model production cross section
$\mu=\sigma/\sigma_\mathrm{SM}$, assuming a Higgs boson mass of 125 GeV. The
best fit value is $\hat{\mu} =$ 0.9 $\pm$ 0.7 (stat) $\pm$ 1.3 (syst) = 0.9
$\pm$ 1.5 (tot), and the observed and expected upper limits are, respectively,
$\mu <$ 3.8 and $<$ 3.1 at 95% confidence levels.
|
hep-ex
|
a search is presented for the associated production of a higgs boson with a top quark pair in the alljet final state events containing seven or more jets are selected from a sample of protonproton collisions at sqrts 13 tev collected with the cms detector at the lhc in 2016 corresponding to an integrated luminosity of 359 fb1 to separate the mathrmtoverlinemathrmth signal from the irreducible mathrmtoverlinemathrmtmathrmboverlinemathrmb background the analysis assigns leading order matrix element signal and background probability densities to each event a likelihoodratio statistic based on these probability densities is used to extract the signal the results are provided in terms of an observed mathrmtoverlinemathrmth signal strength relative to the standard model production cross section musigmasigma_mathrmsm assuming a higgs boson mass of 125 gev the best fit value is hatmu 09 pm 07 stat pm 13 syst 09 pm 15 tot and the observed and expected upper limits are respectively mu 38 and 31 at 95 confidence levels
|
[['a', 'search', 'is', 'presented', 'for', 'the', 'associated', 'production', 'of', 'a', 'higgs', 'boson', 'with', 'a', 'top', 'quark', 'pair', 'in', 'the', 'alljet', 'final', 'state', 'events', 'containing', 'seven', 'or', 'more', 'jets', 'are', 'selected', 'from', 'a', 'sample', 'of', 'protonproton', 'collisions', 'at', 'sqrts', '13', 'tev', 'collected', 'with', 'the', 'cms', 'detector', 'at', 'the', 'lhc', 'in', '2016', 'corresponding', 'to', 'an', 'integrated', 'luminosity', 'of', '359', 'fb1', 'to', 'separate', 'the', 'mathrmtoverlinemathrmth', 'signal', 'from', 'the', 'irreducible', 'mathrmtoverlinemathrmtmathrmboverlinemathrmb', 'background', 'the', 'analysis', 'assigns', 'leading', 'order', 'matrix', 'element', 'signal', 'and', 'background', 'probability', 'densities', 'to', 'each', 'event', 'a', 'likelihoodratio', 'statistic', 'based', 'on', 'these', 'probability', 'densities', 'is', 'used', 'to', 'extract', 'the', 'signal', 'the', 'results', 'are', 'provided', 'in', 'terms', 'of', 'an', 'observed', 'mathrmtoverlinemathrmth', 'signal', 'strength', 'relative', 'to', 'the', 'standard', 'model', 'production', 'cross', 'section', 'musigmasigma_mathrmsm', 'assuming', 'a', 'higgs', 'boson', 'mass', 'of', '125', 'gev', 'the', 'best', 'fit', 'value', 'is', 'hatmu', '09', 'pm', '07', 'stat', 'pm', '13', 'syst', '09', 'pm', '15', 'tot', 'and', 'the', 'observed', 'and', 'expected', 'upper', 'limits', 'are', 'respectively', 'mu', '38', 'and', '31', 'at', '95', 'confidence', 'levels']]
|
[-0.04111035078844557, 0.1535034470138131, -0.06495568384595501, 0.11759714038896327, -0.0063178621960851625, -0.10429865897943576, 0.03827858426852916, 0.3229543002238736, -0.15336168721580926, -0.4007123013934455, 0.036784127821029425, -0.40307245859637475, 0.09477444043985973, 0.1487872725716816, 0.03560794973954893, 0.09074741598958962, 0.09414214432352963, 0.04941673242958645, -0.04014316200911521, -0.2412633111772056, 0.21244131380584663, 0.09638784287903363, 0.2667885080803759, 0.04052874135175863, 0.11218227272314461, 0.0010525863468408203, -0.06698087536810468, -0.10826556699780318, -0.12014320615726785, 0.08141117052862402, 0.24590461403213573, 0.07285019670887731, 0.1316159245775802, -0.2574207065848522, -0.018380958107837405, 0.16306803511001933, 0.11012492939316405, 0.00420646161234263, -0.02303122986342761, -0.3470600874294551, 0.17809139140165195, -0.23192508168852863, -0.0765315283657774, 0.09470288625184017, 0.0356147562016327, -0.08606331976494776, -0.3644976654830269, 0.1546315115530235, -0.08802500351619248, 0.0668353765129443, -0.037658996706924, -0.24107353861192957, -0.10804397708330399, -0.03118642463307016, 0.047664195083481714, 0.11283971285387778, 0.18753189032670492, -0.11712080566884162, -0.18750749656390278, 0.33272654907061505, -0.08282910034027643, -0.1422431843328433, 0.1856211130372965, -0.18834111930575603, -0.10447273402659892, 0.22637897001830146, 0.26048162582521445, 0.0383217721175289, -0.22950347390425846, 0.06223612704809803, 0.0320628641698605, 0.25351296169146037, 0.060816765404664554, 0.019318518209426355, 0.22929147540633446, 0.18936474640996984, 0.010840434372090759, 0.0435231002420784, -0.21273120032893553, -0.03515770367961616, -0.4311721564915318, -0.08879470517739463, -0.0759449351626711, 0.0769040879191986, -0.10549451918781508, -0.03788694388827142, 0.3546937473763067, 0.1269204020530033, 0.3405477215285198, 0.02859571426718806, 0.23039533492201605, 0.15281965323419383, 0.02594978567988922, 0.0816731197365488, 0.31761169301059383, 0.18052082683126897, 0.12193420759509675, -0.1280526792129072, 0.008873486512292845, 0.03771846468738752]
|
1,803.06987
|
Synthesis of Logical Clifford Operators via Symplectic Geometry
|
Quantum error-correcting codes can be used to protect qubits involved in
quantum computation. This requires that logical operators acting on protected
qubits be translated to physical operators (circuits) acting on physical
quantum states. We propose a mathematical framework for synthesizing physical
circuits that implement logical Clifford operators for stabilizer codes.
Circuit synthesis is enabled by representing the desired physical Clifford
operator in $\mathbb{C}^{N \times N}$ as a partial $2m \times 2m$ binary
symplectic matrix, where $N = 2^m$. We state and prove two theorems that use
symplectic transvections to efficiently enumerate all symplectic matrices that
satisfy a system of linear equations. As an important corollary of these
results, we prove that for an $[\![ m,m-k ]\!]$ stabilizer code every logical
Clifford operator has $2^{k(k+1)/2}$ symplectic solutions. The desired physical
circuits are then obtained by decomposing each solution as a product of
elementary symplectic matrices. Our assembly of the possible physical
realizations enables optimization over them with respect to a suitable metric.
Furthermore, we show that any circuit that normalizes the stabilizer of the
code can be transformed into a circuit that centralizes the stabilizer, while
realizing the same logical operation. Our method of circuit synthesis can be
applied to any stabilizer code, and this paper provides a proof of concept
synthesis of universal Clifford gates for the $[\![ 6,4,2 ]\!]$ CSS code. We
conclude with a classical coding-theoretic perspective for constructing logical
Pauli operators for CSS codes. Since our circuit synthesis algorithm builds on
the logical Pauli operators for the code, this paper provides a complete
framework for constructing all logical Clifford operators for CSS codes.
Programs implementing our algorithms can be found at
https://github.com/nrenga/symplectic-arxiv18a
|
cs.IT math.IT quant-ph
|
quantum errorcorrecting codes can be used to protect qubits involved in quantum computation this requires that logical operators acting on protected qubits be translated to physical operators circuits acting on physical quantum states we propose a mathematical framework for synthesizing physical circuits that implement logical clifford operators for stabilizer codes circuit synthesis is enabled by representing the desired physical clifford operator in mathbbcn times n as a partial 2m times 2m binary symplectic matrix where n 2m we state and prove two theorems that use symplectic transvections to efficiently enumerate all symplectic matrices that satisfy a system of linear equations as an important corollary of these results we prove that for an mmk stabilizer code every logical clifford operator has 2kk12 symplectic solutions the desired physical circuits are then obtained by decomposing each solution as a product of elementary symplectic matrices our assembly of the possible physical realizations enables optimization over them with respect to a suitable metric furthermore we show that any circuit that normalizes the stabilizer of the code can be transformed into a circuit that centralizes the stabilizer while realizing the same logical operation our method of circuit synthesis can be applied to any stabilizer code and this paper provides a proof of concept synthesis of universal clifford gates for the 642 css code we conclude with a classical codingtheoretic perspective for constructing logical pauli operators for css codes since our circuit synthesis algorithm builds on the logical pauli operators for the code this paper provides a complete framework for constructing all logical clifford operators for css codes programs implementing our algorithms can be found at httpsgithubcomnrengasymplecticarxiv18a
|
[['quantum', 'errorcorrecting', 'codes', 'can', 'be', 'used', 'to', 'protect', 'qubits', 'involved', 'in', 'quantum', 'computation', 'this', 'requires', 'that', 'logical', 'operators', 'acting', 'on', 'protected', 'qubits', 'be', 'translated', 'to', 'physical', 'operators', 'circuits', 'acting', 'on', 'physical', 'quantum', 'states', 'we', 'propose', 'a', 'mathematical', 'framework', 'for', 'synthesizing', 'physical', 'circuits', 'that', 'implement', 'logical', 'clifford', 'operators', 'for', 'stabilizer', 'codes', 'circuit', 'synthesis', 'is', 'enabled', 'by', 'representing', 'the', 'desired', 'physical', 'clifford', 'operator', 'in', 'mathbbcn', 'times', 'n', 'as', 'a', 'partial', '2m', 'times', '2m', 'binary', 'symplectic', 'matrix', 'where', 'n', '2m', 'we', 'state', 'and', 'prove', 'two', 'theorems', 'that', 'use', 'symplectic', 'transvections', 'to', 'efficiently', 'enumerate', 'all', 'symplectic', 'matrices', 'that', 'satisfy', 'a', 'system', 'of', 'linear', 'equations', 'as', 'an', 'important', 'corollary', 'of', 'these', 'results', 'we', 'prove', 'that', 'for', 'an', 'mmk', 'stabilizer', 'code', 'every', 'logical', 'clifford', 'operator', 'has', '2kk12', 'symplectic', 'solutions', 'the', 'desired', 'physical', 'circuits', 'are', 'then', 'obtained', 'by', 'decomposing', 'each', 'solution', 'as', 'a', 'product', 'of', 'elementary', 'symplectic', 'matrices', 'our', 'assembly', 'of', 'the', 'possible', 'physical', 'realizations', 'enables', 'optimization', 'over', 'them', 'with', 'respect', 'to', 'a', 'suitable', 'metric', 'furthermore', 'we', 'show', 'that', 'any', 'circuit', 'that', 'normalizes', 'the', 'stabilizer', 'of', 'the', 'code', 'can', 'be', 'transformed', 'into', 'a', 'circuit', 'that', 'centralizes', 'the', 'stabilizer', 'while', 'realizing', 'the', 'same', 'logical', 'operation', 'our', 'method', 'of', 'circuit', 'synthesis', 'can', 'be', 'applied', 'to', 'any', 'stabilizer', 'code', 'and', 'this', 'paper', 'provides', 'a', 'proof', 'of', 'concept', 'synthesis', 'of', 'universal', 'clifford', 'gates', 'for', 'the', '642', 'css', 'code', 'we', 'conclude', 'with', 'a', 'classical', 'codingtheoretic', 'perspective', 'for', 'constructing', 'logical', 'pauli', 'operators', 'for', 'css', 'codes', 'since', 'our', 'circuit', 'synthesis', 'algorithm', 'builds', 'on', 'the', 'logical', 'pauli', 'operators', 'for', 'the', 'code', 'this', 'paper', 'provides', 'a', 'complete', 'framework', 'for', 'constructing', 'all', 'logical', 'clifford', 'operators', 'for', 'css', 'codes', 'programs', 'implementing', 'our', 'algorithms', 'can', 'be', 'found', 'at', 'httpsgithubcomnrengasymplecticarxiv18a']]
|
[-0.15327310992394433, 0.10555274435070164, -0.04407828665238054, 0.0549739100598145, -0.042315942533037255, -0.23624821180013808, 0.04856516697468257, 0.3427711155120159, -0.27552091124983413, -0.265476588463821, 0.0938460212127309, -0.21389430784360683, -0.15909383611231662, 0.2636345770957855, -0.11313514069895966, 0.12075847348364478, 0.07445626159382077, 0.011912372440121787, -0.16266010952555163, -0.2615478754313628, 0.3412082381858092, 0.020347407098070175, 0.21330083375554323, -0.017104976710112123, 0.1286463170333118, -0.003582325545992169, 0.01885375204464926, -0.05337406981210172, -0.041479175042431995, 0.12679843672920801, 0.3173524111606264, 0.20415730256635736, 0.19318827153547047, -0.45851909397739044, -0.17244359833572656, 0.0887868764544543, 0.14155835159933092, 0.16723802543702262, -0.027528195490897894, -0.27861584527946, 0.1112389688598179, -0.1869056626001449, -0.07370584158116059, -0.11517268659518408, 0.018241928602338572, -0.059855507326885354, -0.26570298054625996, -0.07964953095011662, 0.10444481872441073, 0.06882833569746838, -0.022018743401954165, -0.1107393872095826, -0.003154785107461161, 0.13723118575012871, -0.14721268848394872, 0.029242641116807508, 0.14437232480006168, 0.012433013986089859, -0.1868392358911414, 0.3425172157170161, -1.9123844393844054e-05, -0.2600219399325522, 0.08991665333045515, -0.0407230225434963, -0.17212950469810018, 0.04471249847160479, 0.1391688998534126, 0.07580239840932051, -0.1354606612464309, 0.14534359196933214, -0.061399485012274026, 0.19758661495535512, 0.054229314090185506, 0.10077359778183377, 0.1364495470837714, 0.0848885434532545, 0.08677766366851374, 0.16866630799410026, 0.038808400259629325, -0.07054060257059871, -0.35449156994138564, -0.19865063625841392, -0.16841388766335316, 0.1307932090907458, -0.10364154736610082, -0.19117894693932125, 0.425677817352947, 0.13523862323335106, 0.11658443707183391, 0.12388223270127433, 0.282017535263444, 0.09575157036674192, 0.13805798548845, 0.13601402562201634, 0.127430950619495, 0.19489682070152717, -0.010104493428018207, -0.1957668094873276, 0.024681468726201573, 0.13318995297416875]
|
1,803.06988
|
Maximal Symmetry and Unimodular Solvmanifolds
|
Recently, it was shown that Einstein solvmanifolds have maximal symmetry in
the sense that their isometry groups contain the isometry groups of any other
left-invariant metric on the given Lie group. Such a solvable Lie group is
necessarily non-unimodular. In this work we consider unimodular solvable Lie
groups and prove that there is always some metric with maximal symmetry.
Further, if the group at hand admits a Ricci soliton, then it is the isometry
group of the Ricci soliton which is maximal.
|
math.DG
|
recently it was shown that einstein solvmanifolds have maximal symmetry in the sense that their isometry groups contain the isometry groups of any other leftinvariant metric on the given lie group such a solvable lie group is necessarily nonunimodular in this work we consider unimodular solvable lie groups and prove that there is always some metric with maximal symmetry further if the group at hand admits a ricci soliton then it is the isometry group of the ricci soliton which is maximal
|
[['recently', 'it', 'was', 'shown', 'that', 'einstein', 'solvmanifolds', 'have', 'maximal', 'symmetry', 'in', 'the', 'sense', 'that', 'their', 'isometry', 'groups', 'contain', 'the', 'isometry', 'groups', 'of', 'any', 'other', 'leftinvariant', 'metric', 'on', 'the', 'given', 'lie', 'group', 'such', 'a', 'solvable', 'lie', 'group', 'is', 'necessarily', 'nonunimodular', 'in', 'this', 'work', 'we', 'consider', 'unimodular', 'solvable', 'lie', 'groups', 'and', 'prove', 'that', 'there', 'is', 'always', 'some', 'metric', 'with', 'maximal', 'symmetry', 'further', 'if', 'the', 'group', 'at', 'hand', 'admits', 'a', 'ricci', 'soliton', 'then', 'it', 'is', 'the', 'isometry', 'group', 'of', 'the', 'ricci', 'soliton', 'which', 'is', 'maximal']]
|
[-0.22139606606527573, 0.12292801732447271, -0.1157871529107868, 0.03703917359518705, -0.2246618365369192, -0.2101925519953777, -0.07745034322596905, 0.46469767282648783, -0.2561165195742122, -0.18264132562070723, 0.18420452645287008, -0.2792532922836339, -0.1778289488681433, 0.14252332741076626, -0.09894119061688643, -0.05629738274302969, 0.04713738424612618, 0.26669999275629114, -0.0991296448784585, -0.318544729479316, 0.43844648341580134, -0.031027332374190048, 0.2809027408635834, 0.03368721880791027, 0.1678985625281135, -0.06341626037979817, 0.03132743371945874, 0.02137464894799561, -0.13297421197687692, 0.05053523455451175, 0.28070547728140544, 0.061693105940343586, 0.1939994764525625, -0.309898756728394, -0.22748779611116865, 0.2724840153440288, 0.14360547032797846, 0.06212242932780078, -0.10572170026787761, -0.33620641900726206, 0.12482448681200878, -0.1458597221956929, -0.1420293691235867, -0.03150439524750521, 0.06376518145567034, -0.07053032032463973, -0.11961838466728605, 0.060598742568910846, 0.10202650462345379, 0.04523729362193901, -0.0769658547587602, -0.0052220417447842475, -0.0776792575843723, 0.06653071045534821, 0.034770429808725946, 0.04895985383176949, 0.1007679006135909, -0.0092649144410133, -0.10229154081770969, 0.4609712752081999, -0.03879960340152427, -0.2705427894777641, 0.11580955373441301, -0.199185858934936, -0.22684165198219622, 0.07381987949356256, 0.05917736094036117, 0.15270934401579747, -0.05494840712877127, 0.2353081800740655, -0.1847950533464006, 0.08137336949159096, 0.09497025802095489, -0.006021009956872682, 0.07839734776786006, 0.06422232080069257, 0.20571448390156302, 0.05681746412230451, 0.15193695847297134, 0.014458146127985745, -0.3399679614003839, -0.17790157564847572, -0.12447326783681424, 0.1476114976770676, -0.14666669857216197, -0.15163346781876655, 0.37812204195595367, 0.023229352482480974, 0.10593566082690548, 0.14452218447340562, 0.15014895755888485, 0.04647354114936983, 0.14261577901055628, 0.1706049388456272, 0.21610944197554335, 0.2254290144050085, -0.10834659505976228, -0.18338982011305122, -0.09343622497669081, 0.2002105006931077]
|
1,803.06989
|
Numerical Integration on Graphs: where to sample and how to weigh
|
Let $G=(V,E,w)$ be a finite, connected graph with weighted edges. We are
interested in the problem of finding a subset $W \subset V$ of vertices and
weights $a_w$ such that $$ \frac{1}{|V|}\sum_{v \in V}^{}{f(v)} \sim \sum_{w
\in W}{a_w f(w)}$$ for functions $f:V \rightarrow \mathbb{R}$ that are `smooth'
with respect to the geometry of the graph. The main application are problems
where $f$ is known to somehow depend on the underlying graph but is expensive
to evaluate on even a single vertex. We prove an inequality showing that the
integration problem can be rewritten as a geometric problem (`the optimal
packing of heat balls'). We discuss how one would construct approximate
solutions of the heat ball packing problem; numerical examples demonstrate the
efficiency of the method.
|
math.ST cs.LG math.NA stat.ML stat.TH
|
let gvew be a finite connected graph with weighted edges we are interested in the problem of finding a subset w subset v of vertices and weights a_w such that frac1vsum_v in vfv sim sum_w in wa_w fw for functions fv rightarrow mathbbr that are smooth with respect to the geometry of the graph the main application are problems where f is known to somehow depend on the underlying graph but is expensive to evaluate on even a single vertex we prove an inequality showing that the integration problem can be rewritten as a geometric problem the optimal packing of heat balls we discuss how one would construct approximate solutions of the heat ball packing problem numerical examples demonstrate the efficiency of the method
|
[['let', 'gvew', 'be', 'a', 'finite', 'connected', 'graph', 'with', 'weighted', 'edges', 'we', 'are', 'interested', 'in', 'the', 'problem', 'of', 'finding', 'a', 'subset', 'w', 'subset', 'v', 'of', 'vertices', 'and', 'weights', 'a_w', 'such', 'that', 'frac1vsum_v', 'in', 'vfv', 'sim', 'sum_w', 'in', 'wa_w', 'fw', 'for', 'functions', 'fv', 'rightarrow', 'mathbbr', 'that', 'are', 'smooth', 'with', 'respect', 'to', 'the', 'geometry', 'of', 'the', 'graph', 'the', 'main', 'application', 'are', 'problems', 'where', 'f', 'is', 'known', 'to', 'somehow', 'depend', 'on', 'the', 'underlying', 'graph', 'but', 'is', 'expensive', 'to', 'evaluate', 'on', 'even', 'a', 'single', 'vertex', 'we', 'prove', 'an', 'inequality', 'showing', 'that', 'the', 'integration', 'problem', 'can', 'be', 'rewritten', 'as', 'a', 'geometric', 'problem', 'the', 'optimal', 'packing', 'of', 'heat', 'balls', 'we', 'discuss', 'how', 'one', 'would', 'construct', 'approximate', 'solutions', 'of', 'the', 'heat', 'ball', 'packing', 'problem', 'numerical', 'examples', 'demonstrate', 'the', 'efficiency', 'of', 'the', 'method']]
|
[-0.11904682002801326, 0.06688511844633288, -0.025764825219502213, 0.03874824358890841, -0.11053440608771244, -0.13072217594771113, 0.04024880324093411, 0.3955662946720592, -0.3304889332808432, -0.2549604592586249, 0.11787459822696038, -0.3316441929563269, -0.14264796315463352, 0.18219853538378586, -0.11998719017815272, 0.04120734615678914, 0.10119594978626634, 0.0940428854722041, -0.036847110408297204, -0.2517315515955876, 0.3137814989771511, -0.0722105239983648, 0.1740573772084212, 0.0925194555559562, 0.10302833140971804, -0.008559185131758329, 0.01602312862695592, 0.06769469222168392, -0.16915961657167694, 0.08440392524324601, 0.2654117826586131, 0.14839976834950083, 0.2991151593503405, -0.39762255660884205, -0.1781973042372675, 0.20818148796603114, 0.13810706948937818, 0.009690279222177495, -0.0019820623260113548, -0.2223750034912077, 0.14028967114653987, -0.09174590446551131, -0.10299020660583114, -0.035241655037799455, 0.051431092872574434, 0.053235187882282695, -0.3104041661364866, 0.023332978020513765, 0.04853791396179404, -0.035148377249734936, -0.013279263941632187, -0.14258072099297261, -0.022847967297716647, 0.07643562821732437, -0.01844913856561494, 0.11362770494058362, 0.09783360216629187, -0.11455334341061658, -0.12488500940705054, 0.3919220120363609, -0.031138569853253296, -0.2730418514101537, 0.12540401447732308, -0.1206980976963141, -0.1266761052032902, 0.08344432825153908, 0.16379741667464498, 0.1653837722222336, -0.08987443906361939, 0.15249886554923503, -0.09917781561933701, 0.12265458783100466, 0.0730381032459621, 0.009845671316486646, 0.12101882651112363, 0.13649384306407855, 0.15495215287550398, 0.187723943465542, -0.001939554320892594, -0.023647199757015486, -0.31938087977621643, -0.13693835291072542, -0.24385084395037324, 0.09576777070684389, -0.1505075754428647, -0.1974195113451388, 0.3650759651829473, 0.10087501803855793, 0.22993111343993272, 0.08884637640812053, 0.22638207865324536, 0.14100765940240875, 0.013011032696355318, 0.12930505650240134, 0.14069513613968843, 0.11911961138553795, 0.01189014603494529, -0.19242311582602867, 0.039603317249948006, 0.13862975599381644]
|
1,803.0699
|
Experimental Molecular Communication Testbed Based on Magnetic
Nanoparticles in Duct Flow
|
Simple and easy to implement testbeds are needed to further advance molecular
communication research. To this end, this paper presents an in-vessel molecular
communication testbed using magnetic nanoparticles dispersed in an aqueous
suspension as they are also used for drug targeting in biotechnology. The
transmitter is realized by an electronic pump for injection via a Y-connector.
A second pump provides a background flow for signal propagation. For signal
reception, we employ a susceptometer, an electronic device including a coil,
where the magnetic particles move through and generate an electrical signal. We
present experimental results for the transmission of a binary sequence and the
system response following a single injection. For this flow-driven particle
transport, we propose a simple parameterized mathematical model for evaluating
the system response.
|
cs.ET
|
simple and easy to implement testbeds are needed to further advance molecular communication research to this end this paper presents an invessel molecular communication testbed using magnetic nanoparticles dispersed in an aqueous suspension as they are also used for drug targeting in biotechnology the transmitter is realized by an electronic pump for injection via a yconnector a second pump provides a background flow for signal propagation for signal reception we employ a susceptometer an electronic device including a coil where the magnetic particles move through and generate an electrical signal we present experimental results for the transmission of a binary sequence and the system response following a single injection for this flowdriven particle transport we propose a simple parameterized mathematical model for evaluating the system response
|
[['simple', 'and', 'easy', 'to', 'implement', 'testbeds', 'are', 'needed', 'to', 'further', 'advance', 'molecular', 'communication', 'research', 'to', 'this', 'end', 'this', 'paper', 'presents', 'an', 'invessel', 'molecular', 'communication', 'testbed', 'using', 'magnetic', 'nanoparticles', 'dispersed', 'in', 'an', 'aqueous', 'suspension', 'as', 'they', 'are', 'also', 'used', 'for', 'drug', 'targeting', 'in', 'biotechnology', 'the', 'transmitter', 'is', 'realized', 'by', 'an', 'electronic', 'pump', 'for', 'injection', 'via', 'a', 'yconnector', 'a', 'second', 'pump', 'provides', 'a', 'background', 'flow', 'for', 'signal', 'propagation', 'for', 'signal', 'reception', 'we', 'employ', 'a', 'susceptometer', 'an', 'electronic', 'device', 'including', 'a', 'coil', 'where', 'the', 'magnetic', 'particles', 'move', 'through', 'and', 'generate', 'an', 'electrical', 'signal', 'we', 'present', 'experimental', 'results', 'for', 'the', 'transmission', 'of', 'a', 'binary', 'sequence', 'and', 'the', 'system', 'response', 'following', 'a', 'single', 'injection', 'for', 'this', 'flowdriven', 'particle', 'transport', 'we', 'propose', 'a', 'simple', 'parameterized', 'mathematical', 'model', 'for', 'evaluating', 'the', 'system', 'response']]
|
[-0.16292298007383943, 0.11849702845478896, -0.06203685881197452, -0.027931153262034058, -0.06804387889429928, -0.16303670923411845, 0.05871508968807757, 0.41786302635073663, -0.27196644265949727, -0.2835606434196234, 0.06043120023747906, -0.23773765804991126, -0.15671697434037923, 0.23027949551027269, -0.03582385800406337, 0.05549415624979884, 0.021126011077314617, -0.012525415156036616, 0.02510914502758533, -0.15956228945124895, 0.22260542162694036, 0.09614077073335647, 0.2701275779530406, 0.047100206257775425, 0.1205923473467119, 0.03500434814207256, 0.05113367329165339, -0.01705945609509945, -0.12496406247606501, 0.11069846107810735, 0.2721966109294444, 0.09961235646158456, 0.2452410810701549, -0.49764707474410536, -0.23490778007358312, 0.05279102517664432, 0.162489973613061, 0.1584752051010728, -0.15470117074251175, -0.23440523158479482, 0.07124698273837567, -0.2046187659939751, -0.08355762217193842, -0.07528400616161525, -0.014491702606901526, 0.03974532772926614, -0.3141476573497057, 0.0070504188255872575, 0.00496710616722703, 0.10756046236306428, -0.0676185906631872, -0.04490625533927232, 0.05178186796605587, 0.15863558408617973, -0.0288961812434718, 0.03304031557589769, 0.20012602481618524, -0.13231129080383108, -0.11901273074001074, 0.39274667571298777, -0.04014494003728032, -0.1983382012275979, 0.1738411599583924, -0.053917792648775505, -0.09424561103060841, 0.13737117154523731, 0.21710873656533658, 0.1029534025862813, -0.2192305019283667, -0.0213384596160613, 0.004279466114938259, 0.1999570001270622, 0.03443420735746622, -0.002140406046062708, 0.22773527966067195, 0.24326654060557484, 0.06493407925590873, 0.19966915714927017, -0.12836873450130223, -0.020545717026339845, -0.24092358531057834, -0.1980571753513068, -0.17772804114222526, 0.057313347477465866, -0.03227596891077701, -0.15860281145572663, 0.41953216946404426, 0.16087842440977693, 0.1368516767770052, 0.02556323393061757, 0.36138124042749403, 0.09078803638648242, -0.015187120817601681, 0.059345838170498606, 0.2333941072449088, 0.12029945148713887, 0.1700918307043612, -0.2103151323108468, 0.05612763984128833, -0.031524468823568894]
|
1,803.06991
|
Jet Substructure at the Large Hadron Collider: Experimental Review
|
Jet substructure has emerged to play a central role at the Large Hadron
Collider, where it has provided numerous innovative ways to search for new
physics and to probe the Standard Model, particularly in extreme regions of
phase space. In this article we focus on a review of the development and use of
state-of-the-art jet substructure techniques by the ATLAS and CMS experiments.
|
hep-ex
|
jet substructure has emerged to play a central role at the large hadron collider where it has provided numerous innovative ways to search for new physics and to probe the standard model particularly in extreme regions of phase space in this article we focus on a review of the development and use of stateoftheart jet substructure techniques by the atlas and cms experiments
|
[['jet', 'substructure', 'has', 'emerged', 'to', 'play', 'a', 'central', 'role', 'at', 'the', 'large', 'hadron', 'collider', 'where', 'it', 'has', 'provided', 'numerous', 'innovative', 'ways', 'to', 'search', 'for', 'new', 'physics', 'and', 'to', 'probe', 'the', 'standard', 'model', 'particularly', 'in', 'extreme', 'regions', 'of', 'phase', 'space', 'in', 'this', 'article', 'we', 'focus', 'on', 'a', 'review', 'of', 'the', 'development', 'and', 'use', 'of', 'stateoftheart', 'jet', 'substructure', 'techniques', 'by', 'the', 'atlas', 'and', 'cms', 'experiments']]
|
[-0.03062908686993141, 0.09332260112499907, -0.13750762891186963, 0.08836493119856136, -0.10486505678041823, -0.08871117797458455, -0.024423092751512453, 0.34871361035084913, -0.20673166095678294, -0.3370159812537687, 0.11091749530122985, -0.27949783361945596, -0.07350030142281737, 0.21837321035416116, 0.011286887658079938, 0.08776509755897144, 0.0819687107430091, -0.04309426294449146, -0.02782530300614853, -0.19935928063378447, 0.3174681418080119, 0.1382714540231973, 0.2534312375540298, 0.07923874410519761, 0.10712786632338686, 0.002183703099569631, -0.09959007370921355, 0.020484364069979787, -0.12916861663735102, 0.15438240433910064, 0.29843496968821875, 0.14321503398333868, 0.2703475138497731, -0.41263634161580176, -0.17962400971483145, 0.10671371946643506, 0.16587953160088215, 0.06437497673230985, -0.16876308414678548, -0.2668260596544733, 0.09259638559102776, -0.23665069779824643, -0.12370784326441704, -0.07785370849102499, 0.02184196362929744, -0.06774248667652645, -0.23947215980539718, 0.0039463950513255975, 0.006305357360000175, 0.07224873981128137, 0.0651923885775937, -0.13852871514649856, 0.030788101189370667, 0.08184207933363578, 0.07709217310831365, 0.09692237744226105, 0.17293648747727275, -0.2204983279899886, -0.17515679267013357, 0.36215379727738245, -0.024964429024193022, -0.11773622159417423, 0.27978704141689437, -0.20024451784168681, -0.22421646971137277, 0.07300317822585976, 0.27777815228771596, 0.07639043804790292, -0.13868232823849197, 0.11569007534611349, -0.011375370221064678, 0.12255031007179429, 0.0159186982468421, 0.07289321178067772, 0.24569464113844175, 0.27039962646270554, 0.06333733769872832, 0.12075929373266205, -0.1515651339118088, -0.0912522700807405, -0.3281970005999837, -0.15055940299117493, -0.09298968885744376, -0.051056383648380964, -0.01174174448672039, -0.10498635683740888, 0.4080224051288078, 0.16129932074349315, 0.25140024859103416, -0.10053662921760291, 0.3058748585837228, 0.01627234580911814, 0.09085068572913149, 0.04440626058988975, 0.31340479026807266, 0.09914288404841154, 0.17017245090877017, -0.17024012866230415, 0.04312692340906887, 0.06373063966424929]
|
1,803.06992
|
Estimating the intrinsic dimension of datasets by a minimal neighborhood
information
|
Analyzing large volumes of high-dimensional data is an issue of fundamental
importance in data science, molecular simulations and beyond. Several
approaches work on the assumption that the important content of a dataset
belongs to a manifold whose Intrinsic Dimension (ID) is much lower than the
crude large number of coordinates. Such manifold is generally twisted and
curved, in addition points on it will be non-uniformly distributed: two factors
that make the identification of the ID and its exploitation really hard. Here
we propose a new ID estimator using only the distance of the first and the
second nearest neighbor of each point in the sample. This extreme minimality
enables us to reduce the effects of curvature, of density variation, and the
resulting computational cost. The ID estimator is theoretically exact in
uniformly distributed datasets, and provides consistent measures in general.
When used in combination with block analysis, it allows discriminating the
relevant dimensions as a function of the block size. This allows estimating the
ID even when the data lie on a manifold perturbed by a high-dimensional noise,
a situation often encountered in real world data sets. We demonstrate the
usefulness of the approach on molecular simulations and image analysis.
|
stat.ML cs.LG
|
analyzing large volumes of highdimensional data is an issue of fundamental importance in data science molecular simulations and beyond several approaches work on the assumption that the important content of a dataset belongs to a manifold whose intrinsic dimension id is much lower than the crude large number of coordinates such manifold is generally twisted and curved in addition points on it will be nonuniformly distributed two factors that make the identification of the id and its exploitation really hard here we propose a new id estimator using only the distance of the first and the second nearest neighbor of each point in the sample this extreme minimality enables us to reduce the effects of curvature of density variation and the resulting computational cost the id estimator is theoretically exact in uniformly distributed datasets and provides consistent measures in general when used in combination with block analysis it allows discriminating the relevant dimensions as a function of the block size this allows estimating the id even when the data lie on a manifold perturbed by a highdimensional noise a situation often encountered in real world data sets we demonstrate the usefulness of the approach on molecular simulations and image analysis
|
[['analyzing', 'large', 'volumes', 'of', 'highdimensional', 'data', 'is', 'an', 'issue', 'of', 'fundamental', 'importance', 'in', 'data', 'science', 'molecular', 'simulations', 'and', 'beyond', 'several', 'approaches', 'work', 'on', 'the', 'assumption', 'that', 'the', 'important', 'content', 'of', 'a', 'dataset', 'belongs', 'to', 'a', 'manifold', 'whose', 'intrinsic', 'dimension', 'id', 'is', 'much', 'lower', 'than', 'the', 'crude', 'large', 'number', 'of', 'coordinates', 'such', 'manifold', 'is', 'generally', 'twisted', 'and', 'curved', 'in', 'addition', 'points', 'on', 'it', 'will', 'be', 'nonuniformly', 'distributed', 'two', 'factors', 'that', 'make', 'the', 'identification', 'of', 'the', 'id', 'and', 'its', 'exploitation', 'really', 'hard', 'here', 'we', 'propose', 'a', 'new', 'id', 'estimator', 'using', 'only', 'the', 'distance', 'of', 'the', 'first', 'and', 'the', 'second', 'nearest', 'neighbor', 'of', 'each', 'point', 'in', 'the', 'sample', 'this', 'extreme', 'minimality', 'enables', 'us', 'to', 'reduce', 'the', 'effects', 'of', 'curvature', 'of', 'density', 'variation', 'and', 'the', 'resulting', 'computational', 'cost', 'the', 'id', 'estimator', 'is', 'theoretically', 'exact', 'in', 'uniformly', 'distributed', 'datasets', 'and', 'provides', 'consistent', 'measures', 'in', 'general', 'when', 'used', 'in', 'combination', 'with', 'block', 'analysis', 'it', 'allows', 'discriminating', 'the', 'relevant', 'dimensions', 'as', 'a', 'function', 'of', 'the', 'block', 'size', 'this', 'allows', 'estimating', 'the', 'id', 'even', 'when', 'the', 'data', 'lie', 'on', 'a', 'manifold', 'perturbed', 'by', 'a', 'highdimensional', 'noise', 'a', 'situation', 'often', 'encountered', 'in', 'real', 'world', 'data', 'sets', 'we', 'demonstrate', 'the', 'usefulness', 'of', 'the', 'approach', 'on', 'molecular', 'simulations', 'and', 'image', 'analysis']]
|
[-0.1054975470181671, 0.03948279170152091, -0.06840816759271547, 0.08506693368661217, -0.06092257346026599, -0.11513870463240891, 0.060668724477873186, 0.3589372400706634, -0.26870731175178664, -0.3037274867971428, 0.14757371347455772, -0.28108418954085207, -0.15210774032748303, 0.19190124316839502, -0.0822151770722121, 0.060843641003302765, 0.06909569271025248, 0.047914338666014376, -0.06609111390687758, -0.23578006989322603, 0.3473910188610898, 0.07257985996315255, 0.30755043236888013, 0.0018595746764913201, 0.10178020634455606, 0.010066447515273467, -0.05534659439057577, 0.024700417128624395, -0.10007612942754349, 0.16819978179759346, 0.23315472160116768, 0.14210910003283062, 0.2977949211304076, -0.38011092983982964, -0.1870972947217524, 0.11883752290043048, 0.12522128615877592, 0.09730858173519664, -0.03245985645480687, -0.2603992590552662, 0.06543378846443375, -0.11633360618026928, -0.11610809589968994, -0.09046693469106686, 0.020510618358384816, -0.009409408362116664, -0.27190982945263387, 0.0731644335994497, 0.04130258933408186, 0.05186670816037804, -0.03799151138286106, -0.10559393585834187, 0.003413414764218032, 0.1400632587572909, 0.03740828781592427, 0.03810808692360297, 0.12374344127252698, -0.11121841326588765, -0.06934212936088442, 0.39340105654904617, -0.03919176871109812, -0.24542417322285473, 0.20642023554071784, -0.14878038661292523, -0.15459117914084344, 0.11606489973026328, 0.20514712876174598, 0.11354291478171945, -0.140736931735446, 0.1062607595420559, -0.04575177841761615, 0.18103094855629023, 0.014194043642492033, 0.01120432594238082, 0.16345695402473212, 0.1893613063299563, 0.09166634835069999, 0.14123130363121164, -0.1398317449213937, -0.09036038237973117, -0.27916833938565105, -0.16619776798353997, -0.23560658126603812, 0.03471800069906749, -0.14636884455750987, -0.15135783018544316, 0.38511996826622635, 0.17068156465305948, 0.21515646313084288, 0.027524318444775417, 0.3261749861948192, 0.06887783344311174, 0.06365709576988593, 0.0970755439682398, 0.17771497333073058, 0.09235716371214948, 0.06998227558797225, -0.16943095607231953, 0.058196472808485854, 0.01668434439576231]
|
1,803.06993
|
Superconductivity at low density near a ferroelectric quantum critical
point: doped SrTiO
|
Recent experiments on electron- or hole-doped SrTiO$_{3}$ have revealed a
hitherto unknown form of superconductivity, where the Fermi energy of the
paired electrons is much lower than the energies of the bosonic excitations
thought to be responsible for the attractive interaction. We show that this
situation requires a fresh look at the problem calling for (i) a systematic
modeling of the dynamical screening of the Coulomb interaction by ionic and
electronic charges, (ii) a transverse optical phonon mediated pair interaction
and (iii) a determination of the energy range over which the pairing takes
place. We argue that the latter is essentially given by the limiting energy
beyond which quasiparticles cease to be well defined. The model allows to find
the transition temperature as a function of both, the doping concentration and
the dielectric properties of the host system, in good agreement with
experimental data. The additional interaction mediated by the transverse
optical soft phonon is shown to be essential in explaining the observed
anomalous isotope effect. The model allows to capture the effect of the
incipient (or real) ferroelectric phase in pure, or oxygen isotope substituted
SrTiO$_{3}$ .
|
cond-mat.supr-con cond-mat.str-el
|
recent experiments on electron or holedoped srtio_3 have revealed a hitherto unknown form of superconductivity where the fermi energy of the paired electrons is much lower than the energies of the bosonic excitations thought to be responsible for the attractive interaction we show that this situation requires a fresh look at the problem calling for i a systematic modeling of the dynamical screening of the coulomb interaction by ionic and electronic charges ii a transverse optical phonon mediated pair interaction and iii a determination of the energy range over which the pairing takes place we argue that the latter is essentially given by the limiting energy beyond which quasiparticles cease to be well defined the model allows to find the transition temperature as a function of both the doping concentration and the dielectric properties of the host system in good agreement with experimental data the additional interaction mediated by the transverse optical soft phonon is shown to be essential in explaining the observed anomalous isotope effect the model allows to capture the effect of the incipient or real ferroelectric phase in pure or oxygen isotope substituted srtio_3
|
[['recent', 'experiments', 'on', 'electron', 'or', 'holedoped', 'srtio_3', 'have', 'revealed', 'a', 'hitherto', 'unknown', 'form', 'of', 'superconductivity', 'where', 'the', 'fermi', 'energy', 'of', 'the', 'paired', 'electrons', 'is', 'much', 'lower', 'than', 'the', 'energies', 'of', 'the', 'bosonic', 'excitations', 'thought', 'to', 'be', 'responsible', 'for', 'the', 'attractive', 'interaction', 'we', 'show', 'that', 'this', 'situation', 'requires', 'a', 'fresh', 'look', 'at', 'the', 'problem', 'calling', 'for', 'i', 'a', 'systematic', 'modeling', 'of', 'the', 'dynamical', 'screening', 'of', 'the', 'coulomb', 'interaction', 'by', 'ionic', 'and', 'electronic', 'charges', 'ii', 'a', 'transverse', 'optical', 'phonon', 'mediated', 'pair', 'interaction', 'and', 'iii', 'a', 'determination', 'of', 'the', 'energy', 'range', 'over', 'which', 'the', 'pairing', 'takes', 'place', 'we', 'argue', 'that', 'the', 'latter', 'is', 'essentially', 'given', 'by', 'the', 'limiting', 'energy', 'beyond', 'which', 'quasiparticles', 'cease', 'to', 'be', 'well', 'defined', 'the', 'model', 'allows', 'to', 'find', 'the', 'transition', 'temperature', 'as', 'a', 'function', 'of', 'both', 'the', 'doping', 'concentration', 'and', 'the', 'dielectric', 'properties', 'of', 'the', 'host', 'system', 'in', 'good', 'agreement', 'with', 'experimental', 'data', 'the', 'additional', 'interaction', 'mediated', 'by', 'the', 'transverse', 'optical', 'soft', 'phonon', 'is', 'shown', 'to', 'be', 'essential', 'in', 'explaining', 'the', 'observed', 'anomalous', 'isotope', 'effect', 'the', 'model', 'allows', 'to', 'capture', 'the', 'effect', 'of', 'the', 'incipient', 'or', 'real', 'ferroelectric', 'phase', 'in', 'pure', 'or', 'oxygen', 'isotope', 'substituted', 'srtio_3']]
|
[-0.12077017344053795, 0.20709490096993385, -0.05305707138430148, 0.09113335187103659, -0.037784103133259986, -0.14566578017111947, 0.09024166793906115, 0.357617938114121, -0.2452698297534676, -0.3013093447646395, -0.015325013761667604, -0.30459441241380547, -0.09634558518322553, 0.17058833584782074, 0.059796374978467744, -0.009077922630318027, -0.013631139302944994, 0.02161582010389769, -0.07260820766871068, -0.18173273077812344, 0.29841776437220724, 0.06668822746225857, 0.2892217968720046, 0.13257600877304526, 0.05120792901106079, 0.028741862812580014, 0.04770485401890654, 0.023257242179510588, -0.10019554180769501, 0.07657892918799392, 0.24787613539707493, -0.05103901591659947, 0.2250647961167011, -0.4455691881497754, -0.22689217794499794, 0.07250268292678072, 0.14809864933258868, 0.14026498873867493, -0.0793893859867395, -0.26014057396447915, -0.008886493473527903, -0.16413179552431573, -0.12191702381901962, -0.05220760311433338, 0.007605992166081413, -0.0016866049823913982, -0.2714289443350751, 0.10928125408749509, 0.06608734220091408, 0.05250373246138268, -0.12253405557718765, -0.11943298388698342, -0.06949447063405212, 0.07385454361107857, 0.07574323418583344, 0.04729989383812934, 0.1529948534244761, -0.13004233839144722, -0.062010633619751204, 0.40304067051336967, -0.03333232118998702, -0.10579363820778037, 0.19226106919004596, -0.17644525736503125, -0.06102943053110478, 0.16667686511119978, 0.1111920464420965, 0.07016772339942262, -0.14362568481959762, 0.07570996793926016, -0.005244617370320833, 0.17433576105550969, 0.0163026055866444, 0.0912155301809634, 0.2416138616116608, 0.20200157490774323, 0.006279346460904826, 0.1213265948830531, -0.10881137507120994, -0.05406568628327453, -0.2505744156890853, -0.16560820245089378, -0.19144317232704855, 0.05998944069562669, -0.051148082194168165, -0.17075926917377873, 0.39340481527705606, 0.14236170313455523, 0.21326014460475348, -0.053493048328368424, 0.2525661613911709, 0.1266583299848256, 0.10456354802326215, 0.021129093988285583, 0.28625898600560934, 0.1076765775040569, 0.08541573429253589, -0.2987384957580125, 0.10227439257771992, 0.03250349101480993]
|
1,803.06994
|
Inertial Symmetry Breaking
|
We review and expand upon recent work demonstrating that Weyl invariant
theories can be broken "inertially," which does not depend upon a potential.
This can be understood in a general way by the "current algebra" of these
theories, independently of specific Lagrangians. Maintaining the exact Weyl
invariance in a renormalized quantum theory can be accomplished by
renormalization conditions that refer back to the VEV's of fields in the
action. We illustrate the computation of a Weyl invariant Coleman-Weinberg
potential that breaks a U(1) symmetry together,with scale invariance.
|
hep-th astro-ph.CO hep-ph
|
we review and expand upon recent work demonstrating that weyl invariant theories can be broken inertially which does not depend upon a potential this can be understood in a general way by the current algebra of these theories independently of specific lagrangians maintaining the exact weyl invariance in a renormalized quantum theory can be accomplished by renormalization conditions that refer back to the vevs of fields in the action we illustrate the computation of a weyl invariant colemanweinberg potential that breaks a u1 symmetry togetherwith scale invariance
|
[['we', 'review', 'and', 'expand', 'upon', 'recent', 'work', 'demonstrating', 'that', 'weyl', 'invariant', 'theories', 'can', 'be', 'broken', 'inertially', 'which', 'does', 'not', 'depend', 'upon', 'a', 'potential', 'this', 'can', 'be', 'understood', 'in', 'a', 'general', 'way', 'by', 'the', 'current', 'algebra', 'of', 'these', 'theories', 'independently', 'of', 'specific', 'lagrangians', 'maintaining', 'the', 'exact', 'weyl', 'invariance', 'in', 'a', 'renormalized', 'quantum', 'theory', 'can', 'be', 'accomplished', 'by', 'renormalization', 'conditions', 'that', 'refer', 'back', 'to', 'the', 'vevs', 'of', 'fields', 'in', 'the', 'action', 'we', 'illustrate', 'the', 'computation', 'of', 'a', 'weyl', 'invariant', 'colemanweinberg', 'potential', 'that', 'breaks', 'a', 'u1', 'symmetry', 'togetherwith', 'scale', 'invariance']]
|
[-0.18618614106915546, 0.23811976490325706, -0.12506661272261205, 0.05146706746864067, -0.12468573870949534, -0.16969816413502273, 0.03161396874726728, 0.3371563080784886, -0.27017099286299634, -0.2671596148744399, 0.06573893170029488, -0.17487808308282562, -0.18075063811658426, 0.10479230526225576, -0.0841051554033224, 0.02897245138829444, -0.03285134246377924, 0.04557093159230643, -0.16668478266043632, -0.26097617375252896, 0.3286635049694586, 0.05373827465349635, 0.3089980670402563, 0.08569947557069015, 0.07365119527500166, -0.036783135404030595, 0.01432589785910623, 0.048797975240145314, -0.08275667818249298, 0.08505732527132644, 0.20065501598143126, 0.04352912664153548, 0.20666294424188172, -0.44711914454955, -0.23460392995066073, 0.05634449745615035, 0.19222245762817736, 0.18027309887517287, -0.05494320543136361, -0.3461439340960148, 0.08077054097165548, -0.18992934732015657, -0.17583553861761683, -0.15871403483284074, -0.06081570641051025, -0.06625236297935941, -0.22007014818467893, 0.07483638109379383, 0.04605841846340661, 0.05319415169313203, -0.040839647476258144, 0.006926393755007709, -0.048422722822748294, 0.09158074830355513, 0.10177239583978473, 0.05785243187727796, 0.16290178039073294, -0.15972354042961068, -0.1392823453332016, 0.4111372386971705, -0.0872989424970001, -0.22844674962377826, 0.1317732804779743, -0.11104071036124667, -0.19270284557281886, 0.060172361191795316, 0.10664491602327934, 0.14040953804587208, -0.13890653941509595, 0.23220335684519067, -0.04299321914698149, 0.0847886569289014, 0.05959614235258033, 0.010324161603294184, 0.2585435439399335, 0.02424049226913688, 0.07733848379778697, 0.0762001052999674, 0.05925427552659151, -0.10365357538035443, -0.4087551811190192, -0.16214301501438672, -0.19805752660342774, 0.11578617433135446, -0.048909021118963086, -0.1109208096858374, 0.4468062790543881, 0.18098304337611407, 0.21285230728667662, 0.04966479202131416, 0.21832300602393442, 0.14349534879113698, 0.17609127467974675, 0.028838676064773354, 0.2599432279334165, 0.10618954429911925, 0.042728980255941316, -0.2272896049111042, -0.027657075632136142, 0.1434967261955662]
|
1,803.06995
|
Combined dynamical effects of the bar and spiral arms in a Galaxy model.
Application to the solar neighbourhood
|
Observational data indicate that the Milky Way is a barred spiral galaxy.
Computation facilities and availability of data from Galactic surveys stimulate
the appearance of models of the Galactic structure. More efforts to build
dynamical models containing both spiral arms and the central bar/bulge are
needed.
We expand the study of the stellar dynamics in the Galaxy by adding the
bar/bulge component to a model with spiral arms introduced in our previous
paper. The model is tested by applying it to the solar neighborhood, where
observational data are more precise.
We model analytically the potential of the Galaxy to derive the force field
in its equatorial plane. The model comprises an axisymmetric disc derived from
the observable rotation curve, four arms with Gaussian-shaped groove profiles,
and a classical elongated/oblate ellipsoidal bar/bulge structure. The
parameters describing the bar/bulge are constrained by observations and the
stellar dynamics, and their possible limits are determined.
A basic model results in a bar of 2.9 kpc in length, with a mass of the order
of a few 10$^9M_\odot$. The size and orientation of the bar are also restricted
by the position of masers with VLBI distances. The bar's rotation speed is
constrained to $\Omega_{\rm bar}<50$ km s$^{-1}$ kpc$^{-1}$ taking into account
the allowed mass range.
We conclude that our basic model is compatible with observations and with the
dynamical constraints. The model explains simultaneously the bulk of the main
moving groups, associated here with the spiral corotation resonance, and the
Hercules stream, associated with several inner high-order spiral resonances; in
particular, with the 8/1 resonance. From the dynamical constraints on the bar's
angular speed, it is unlikely that the bar's OLR lies near the solar circle;
moreover, its proximity would compromise the stability of the Local Arm
structure.
|
astro-ph.GA
|
observational data indicate that the milky way is a barred spiral galaxy computation facilities and availability of data from galactic surveys stimulate the appearance of models of the galactic structure more efforts to build dynamical models containing both spiral arms and the central barbulge are needed we expand the study of the stellar dynamics in the galaxy by adding the barbulge component to a model with spiral arms introduced in our previous paper the model is tested by applying it to the solar neighborhood where observational data are more precise we model analytically the potential of the galaxy to derive the force field in its equatorial plane the model comprises an axisymmetric disc derived from the observable rotation curve four arms with gaussianshaped groove profiles and a classical elongatedoblate ellipsoidal barbulge structure the parameters describing the barbulge are constrained by observations and the stellar dynamics and their possible limits are determined a basic model results in a bar of 29 kpc in length with a mass of the order of a few 109m_odot the size and orientation of the bar are also restricted by the position of masers with vlbi distances the bars rotation speed is constrained to omega_rm bar50 km s1 kpc1 taking into account the allowed mass range we conclude that our basic model is compatible with observations and with the dynamical constraints the model explains simultaneously the bulk of the main moving groups associated here with the spiral corotation resonance and the hercules stream associated with several inner highorder spiral resonances in particular with the 81 resonance from the dynamical constraints on the bars angular speed it is unlikely that the bars olr lies near the solar circle moreover its proximity would compromise the stability of the local arm structure
|
[['observational', 'data', 'indicate', 'that', 'the', 'milky', 'way', 'is', 'a', 'barred', 'spiral', 'galaxy', 'computation', 'facilities', 'and', 'availability', 'of', 'data', 'from', 'galactic', 'surveys', 'stimulate', 'the', 'appearance', 'of', 'models', 'of', 'the', 'galactic', 'structure', 'more', 'efforts', 'to', 'build', 'dynamical', 'models', 'containing', 'both', 'spiral', 'arms', 'and', 'the', 'central', 'barbulge', 'are', 'needed', 'we', 'expand', 'the', 'study', 'of', 'the', 'stellar', 'dynamics', 'in', 'the', 'galaxy', 'by', 'adding', 'the', 'barbulge', 'component', 'to', 'a', 'model', 'with', 'spiral', 'arms', 'introduced', 'in', 'our', 'previous', 'paper', 'the', 'model', 'is', 'tested', 'by', 'applying', 'it', 'to', 'the', 'solar', 'neighborhood', 'where', 'observational', 'data', 'are', 'more', 'precise', 'we', 'model', 'analytically', 'the', 'potential', 'of', 'the', 'galaxy', 'to', 'derive', 'the', 'force', 'field', 'in', 'its', 'equatorial', 'plane', 'the', 'model', 'comprises', 'an', 'axisymmetric', 'disc', 'derived', 'from', 'the', 'observable', 'rotation', 'curve', 'four', 'arms', 'with', 'gaussianshaped', 'groove', 'profiles', 'and', 'a', 'classical', 'elongatedoblate', 'ellipsoidal', 'barbulge', 'structure', 'the', 'parameters', 'describing', 'the', 'barbulge', 'are', 'constrained', 'by', 'observations', 'and', 'the', 'stellar', 'dynamics', 'and', 'their', 'possible', 'limits', 'are', 'determined', 'a', 'basic', 'model', 'results', 'in', 'a', 'bar', 'of', '29', 'kpc', 'in', 'length', 'with', 'a', 'mass', 'of', 'the', 'order', 'of', 'a', 'few', '109m_odot', 'the', 'size', 'and', 'orientation', 'of', 'the', 'bar', 'are', 'also', 'restricted', 'by', 'the', 'position', 'of', 'masers', 'with', 'vlbi', 'distances', 'the', 'bars', 'rotation', 'speed', 'is', 'constrained', 'to', 'omega_rm', 'bar50', 'km', 's1', 'kpc1', 'taking', 'into', 'account', 'the', 'allowed', 'mass', 'range', 'we', 'conclude', 'that', 'our', 'basic', 'model', 'is', 'compatible', 'with', 'observations', 'and', 'with', 'the', 'dynamical', 'constraints', 'the', 'model', 'explains', 'simultaneously', 'the', 'bulk', 'of', 'the', 'main', 'moving', 'groups', 'associated', 'here', 'with', 'the', 'spiral', 'corotation', 'resonance', 'and', 'the', 'hercules', 'stream', 'associated', 'with', 'several', 'inner', 'highorder', 'spiral', 'resonances', 'in', 'particular', 'with', 'the', '81', 'resonance', 'from', 'the', 'dynamical', 'constraints', 'on', 'the', 'bars', 'angular', 'speed', 'it', 'is', 'unlikely', 'that', 'the', 'bars', 'olr', 'lies', 'near', 'the', 'solar', 'circle', 'moreover', 'its', 'proximity', 'would', 'compromise', 'the', 'stability', 'of', 'the', 'local', 'arm', 'structure']]
|
[-0.12646824182843297, 0.07020197626923594, -0.07399264998730203, 0.05132198390107653, -0.1084005170945027, -0.05591478405473914, 0.013080730183666917, 0.37477313233635473, -0.23604527041652076, -0.33104990329273376, 0.0776623566254903, -0.26356270763810236, -0.07996797961458128, 0.19042600509054525, -0.008594644695894051, 0.01472970243516183, 0.03945469783532635, -0.014709526920991972, -0.05593317984847378, -0.2193933186654155, 0.2934384751829712, 0.06421201721576276, 0.15417476286159515, -0.059957508824260014, 0.0587230746964748, -0.07201969456183645, -0.04159203894385153, 0.0041516562427723735, -0.18131538998225885, 0.10842844423209078, 0.1762769509915631, 0.11664088996079441, 0.2099131947532104, -0.4224835061772224, -0.18614095394400387, 0.036052315565917474, 0.1666347469375997, 0.08589722282758072, -0.045035828129869254, -0.3005211271999301, 0.06228610031511571, -0.15378330257248357, -0.2074364600191053, 0.04053521816337904, 0.03676345094572753, 0.05103887251459856, -0.23408267367451174, 0.11803509043423616, 0.05375499293398947, 0.0708468653120843, -0.09349164397046097, -0.08736332853507135, -0.07180360439505518, 0.09282141223012172, 0.04565384179954343, 0.09091273380469057, 0.19719031530662834, -0.13479200117306023, -0.05262003581942126, 0.418808296417235, -0.05551284620989613, -0.12326945373866487, 0.1952630713689253, -0.21962457086372467, -0.10743900709161439, 0.1035545416707589, 0.1639600424672064, 0.06879206687608842, -0.1267675352303325, 0.05978093595048765, -0.06889943367900819, 0.1825591452368551, 0.030843180148219018, 0.01225185859243304, 0.2937531052641347, 0.13698744169225166, 0.06317785750959337, 0.08347395943522555, -0.208604210044763, -0.11135624851223364, -0.2686508734645706, -0.05276462394436918, -0.08347771054052162, -0.0023215048277552184, -0.13067525855159143, -0.09923753046264225, 0.39565818112734, 0.12392497948619707, 0.2682386591640074, 0.043700786267448846, 0.3294521246811125, 0.057231235373093145, 0.1298377009651134, 0.11088474847126714, 0.3148041841353184, 0.17787397731794843, 0.027765266120808256, -0.2576754694105257, 0.07778308573146943, -0.023052992333003553]
|
1,803.06996
|
Thermodynamics via inducing
|
We consider continuous maps $f:X\to X$ on compact metric spaces admitting
inducing schemes of hyperbolic type introduced in [15] as well as the induced
maps $\tilde{f}:\tilde{X}\to\tilde{X}$ and the associated tower maps
$\hat{f}:\hat{X} \to \hat {X}$. For a certain class of potential functions
$\varphi$ on $X$, which includes all H\"older continuous functions, we
establish thermodynamic formalism for each of the above three systems and we
describe some relations between the corresponding equilibrium measures.
Furthermore we study ergodic properties of these equilibrium measures including
the Bernoulli property, decay of correlations, and the Central Limit Theorem
(CLT). Finally, we prove analyticity of the pressure function for the three
systems.
|
math.DS
|
we consider continuous maps fxto x on compact metric spaces admitting inducing schemes of hyperbolic type introduced in 15 as well as the induced maps tildeftildextotildex and the associated tower maps hatfhatx to hat x for a certain class of potential functions varphi on x which includes all holder continuous functions we establish thermodynamic formalism for each of the above three systems and we describe some relations between the corresponding equilibrium measures furthermore we study ergodic properties of these equilibrium measures including the bernoulli property decay of correlations and the central limit theorem clt finally we prove analyticity of the pressure function for the three systems
|
[['we', 'consider', 'continuous', 'maps', 'fxto', 'x', 'on', 'compact', 'metric', 'spaces', 'admitting', 'inducing', 'schemes', 'of', 'hyperbolic', 'type', 'introduced', 'in', '15', 'as', 'well', 'as', 'the', 'induced', 'maps', 'tildeftildextotildex', 'and', 'the', 'associated', 'tower', 'maps', 'hatfhatx', 'to', 'hat', 'x', 'for', 'a', 'certain', 'class', 'of', 'potential', 'functions', 'varphi', 'on', 'x', 'which', 'includes', 'all', 'holder', 'continuous', 'functions', 'we', 'establish', 'thermodynamic', 'formalism', 'for', 'each', 'of', 'the', 'above', 'three', 'systems', 'and', 'we', 'describe', 'some', 'relations', 'between', 'the', 'corresponding', 'equilibrium', 'measures', 'furthermore', 'we', 'study', 'ergodic', 'properties', 'of', 'these', 'equilibrium', 'measures', 'including', 'the', 'bernoulli', 'property', 'decay', 'of', 'correlations', 'and', 'the', 'central', 'limit', 'theorem', 'clt', 'finally', 'we', 'prove', 'analyticity', 'of', 'the', 'pressure', 'function', 'for', 'the', 'three', 'systems']]
|
[-0.1533478622082979, 0.10696700696336428, -0.0798215085233096, 0.12940429845072615, 0.016707213532824356, -0.11076424633099052, 0.05755814797997188, 0.3738694881590513, -0.3116669782007543, -0.18067450681701303, 0.10248403367474496, -0.29269985073747545, -0.13888720626486106, 0.22471177508347095, -0.04715117712532027, 0.07838962577247563, -0.027381364759863712, 0.043236053512933165, -0.1636666599190973, -0.17820800086169933, 0.4243042013034798, -0.078634100410944, 0.2409274509140792, 0.06427516893969508, 0.17339490834945956, 0.03560456927292622, -0.03566053827167847, 0.028236523230309382, -0.21420077135105833, 0.08071197631383817, 0.19173535904309785, 0.11070520653783415, 0.24701410378642882, -0.3135904233293751, -0.19488063290751037, 0.20805714077925166, 0.05023672780953348, -0.014386337667999145, -0.008076625773145888, -0.2918150453882005, 0.0847822594380257, -0.15250987770895547, -0.1764098685906412, -0.11754115234809713, 0.013563489666781746, 0.11860113129548083, -0.2688584985287609, 0.0513228031520087, 0.13040705988420925, 0.06198648621256535, -0.1144301323667885, -0.08995839364853545, -0.06887265957685976, 0.14235866102927291, 0.014611759692063341, 0.043166458304487884, 0.13164203410717443, -0.0793906849128409, -0.09195334828893045, 0.33954344102396417, -0.10399350719448054, -0.23866167743332112, 0.1947396927862428, -0.1973266838825881, -0.2039266281107512, 0.0674845473975158, 0.164170496738874, 0.12723904372586942, -0.12007869664096059, 0.14272076411613782, -0.05685953203087243, 0.09239293685935152, 0.0766946844143184, 0.09622374226231702, 0.13018642930994526, 0.06910705259696652, 0.13074611980790415, 0.19102596040241993, -0.02854702547427643, -0.09521842644664083, -0.3644516801980969, -0.1649151592414455, -0.11296889642947533, 0.10269764073802015, -0.12985763877874817, -0.1989472210049056, 0.3593656923980094, 0.07767282924704397, 0.18253852144026986, 0.12206565083313482, 0.18701897888632418, 0.13599917995396446, 0.001119694860580449, 0.05779264443733085, 0.14952223606171453, 0.1876825833930455, 0.04493528985991501, -0.13972352293785661, 0.00505500750687833, 0.1650584068086643]
|
1,803.06997
|
Comments on the SU(4) dark matter
|
We discuss possible scale of $SU(4)$ dark matter, in form of neutral baryons.
We argue that it is very likely that those would have time to cluster into
large "nuclear drops" in which they are Bose-condensed.
|
hep-ph
|
we discuss possible scale of su4 dark matter in form of neutral baryons we argue that it is very likely that those would have time to cluster into large nuclear drops in which they are bosecondensed
|
[['we', 'discuss', 'possible', 'scale', 'of', 'su4', 'dark', 'matter', 'in', 'form', 'of', 'neutral', 'baryons', 'we', 'argue', 'that', 'it', 'is', 'very', 'likely', 'that', 'those', 'would', 'have', 'time', 'to', 'cluster', 'into', 'large', 'nuclear', 'drops', 'in', 'which', 'they', 'are', 'bosecondensed']]
|
[-0.1198077967338678, 0.2538566675502807, -0.1459794638471471, 0.15741187858252992, -0.057841531712458365, -0.12523511414959407, -0.011360337905999687, 0.4139010837922494, -0.19671086928186318, -0.31748502432472175, 0.04519642676718326, -0.280113007226545, -0.043281967441240944, 0.10621029045432806, 0.026829556199825473, -0.03791814957124492, -0.006338795265441554, 0.04279384048034748, -0.03668011042464059, -0.2864490749198012, 0.34405871434137225, 0.008788839706944095, 0.17092804238200188, 0.0711142375625463, 0.025817643825171724, -0.11176454603102887, -0.012384508607081242, 0.008508966873503394, -0.07504624098793203, 0.027079684090697102, 0.2760670982922117, 0.1054431771626696, 0.21717351453197706, -0.48395685763615703, -0.15314374703706968, 0.166201234019051, 0.20785209361929446, 0.220425799291762, -0.09798272722400725, -0.28395238218622076, 0.10567942538505627, -0.2051230618963018, -0.1472405121765203, -0.13387450865573353, 0.06404604473047787, -0.005655952781024907, -0.15791275429849824, 0.14210743647547336, 0.002222119959899121, -0.10403696318583873, -0.06359768579972701, -0.14609914924949408, -0.005930884016884698, 0.02068159558499853, 0.0915838551073749, 0.010531085375179019, 0.21670191200812244, -0.22277690452109608, -0.0024776802812185553, 0.4676920808851719, -0.07135443901643157, -0.09193033431397958, 0.2337205703628974, -0.21039630211372343, -0.21519883006759402, 0.1281999854577912, 0.17690502986725834, 0.04230392020609644, -0.1346337185241282, 0.044145887019112706, -0.12708886340260506, 0.18555644361509216, 0.027139095395493012, 0.08125051574057175, 0.30482732768480975, 0.1633722173412227, 0.03829772415338084, 0.07120170340769821, -0.07826786229593886, -0.11964810379787297, -0.2797330359203948, -0.128882815505171, -0.1333326554676104, 0.07297088192879325, -0.033975815452221364, -0.1032312929423319, 0.2910832671590874, 0.1334700675603623, 0.22872438377493787, -0.019368672552647896, 0.2245748318059163, 0.07321612254923417, 0.13502480798504418, 0.07675908993567443, 0.3160384233213133, 0.10369789471021956, 0.03708317834470007, -0.21183982704921314, -0.010516411650718914, -0.037773252212597676]
|
1,803.06998
|
A synergistic view of magnetism, chemical activation, and ORR as well as
OER catalysis of carbon doped hexagonal boron nitride from first-principles
|
Carbon(C) doped hexagonal boron nitride(hBN) has been experimentally reported
in recent years to be a possible catalytic host to oxygen reduction
reaction(ORR), as well as a possible ferromagnet at room temperature.
Substitution by C in hBN has been also reported to form islands of graphene. In
this work, we explore from first principles, the connection between these
different aspects of C doped hBN. We find formation of graphene islands
covering unequal number of B and N sites in hBN to be energetically plausible.
They possess a net non-zero magnetic moment and are also found to be
substantially more chemically active than their non-magnetic counterparts
covering equal number of B and N sites. On-site Coulomb repulsion between
electrons, known to be responsible for magnetism in bipartite lattices like
graphene and hBN, is also found to play a central role in chemical activation
of not only the C atoms at the zigzag interface of magnetic graphene islands
and hBN, but also of boron(B) sites in the immediate hBN neighborhood. However,
such activated B or C due to substitution at B site, which is energetically
more favorable than at N site, has been reported to be unfavorable for ORR.
Advantageously, we find that the activation of C at B sites moderates
systematically with increasing size of graphene islands, paving the way for
abundance of efficient catalytic sites at the edges of magnetic graphene
islands covering more B sites than N sites. Accordingly, as an alternate to
precious metals for electrodes, we propose a class of graphene-hBN hybrids with
lattices of magnetic graphene islands embedded in hBN, which can be metallic.
|
cond-mat.mtrl-sci
|
carbonc doped hexagonal boron nitridehbn has been experimentally reported in recent years to be a possible catalytic host to oxygen reduction reactionorr as well as a possible ferromagnet at room temperature substitution by c in hbn has been also reported to form islands of graphene in this work we explore from first principles the connection between these different aspects of c doped hbn we find formation of graphene islands covering unequal number of b and n sites in hbn to be energetically plausible they possess a net nonzero magnetic moment and are also found to be substantially more chemically active than their nonmagnetic counterparts covering equal number of b and n sites onsite coulomb repulsion between electrons known to be responsible for magnetism in bipartite lattices like graphene and hbn is also found to play a central role in chemical activation of not only the c atoms at the zigzag interface of magnetic graphene islands and hbn but also of boronb sites in the immediate hbn neighborhood however such activated b or c due to substitution at b site which is energetically more favorable than at n site has been reported to be unfavorable for orr advantageously we find that the activation of c at b sites moderates systematically with increasing size of graphene islands paving the way for abundance of efficient catalytic sites at the edges of magnetic graphene islands covering more b sites than n sites accordingly as an alternate to precious metals for electrodes we propose a class of graphenehbn hybrids with lattices of magnetic graphene islands embedded in hbn which can be metallic
|
[['carbonc', 'doped', 'hexagonal', 'boron', 'nitridehbn', 'has', 'been', 'experimentally', 'reported', 'in', 'recent', 'years', 'to', 'be', 'a', 'possible', 'catalytic', 'host', 'to', 'oxygen', 'reduction', 'reactionorr', 'as', 'well', 'as', 'a', 'possible', 'ferromagnet', 'at', 'room', 'temperature', 'substitution', 'by', 'c', 'in', 'hbn', 'has', 'been', 'also', 'reported', 'to', 'form', 'islands', 'of', 'graphene', 'in', 'this', 'work', 'we', 'explore', 'from', 'first', 'principles', 'the', 'connection', 'between', 'these', 'different', 'aspects', 'of', 'c', 'doped', 'hbn', 'we', 'find', 'formation', 'of', 'graphene', 'islands', 'covering', 'unequal', 'number', 'of', 'b', 'and', 'n', 'sites', 'in', 'hbn', 'to', 'be', 'energetically', 'plausible', 'they', 'possess', 'a', 'net', 'nonzero', 'magnetic', 'moment', 'and', 'are', 'also', 'found', 'to', 'be', 'substantially', 'more', 'chemically', 'active', 'than', 'their', 'nonmagnetic', 'counterparts', 'covering', 'equal', 'number', 'of', 'b', 'and', 'n', 'sites', 'onsite', 'coulomb', 'repulsion', 'between', 'electrons', 'known', 'to', 'be', 'responsible', 'for', 'magnetism', 'in', 'bipartite', 'lattices', 'like', 'graphene', 'and', 'hbn', 'is', 'also', 'found', 'to', 'play', 'a', 'central', 'role', 'in', 'chemical', 'activation', 'of', 'not', 'only', 'the', 'c', 'atoms', 'at', 'the', 'zigzag', 'interface', 'of', 'magnetic', 'graphene', 'islands', 'and', 'hbn', 'but', 'also', 'of', 'boronb', 'sites', 'in', 'the', 'immediate', 'hbn', 'neighborhood', 'however', 'such', 'activated', 'b', 'or', 'c', 'due', 'to', 'substitution', 'at', 'b', 'site', 'which', 'is', 'energetically', 'more', 'favorable', 'than', 'at', 'n', 'site', 'has', 'been', 'reported', 'to', 'be', 'unfavorable', 'for', 'orr', 'advantageously', 'we', 'find', 'that', 'the', 'activation', 'of', 'c', 'at', 'b', 'sites', 'moderates', 'systematically', 'with', 'increasing', 'size', 'of', 'graphene', 'islands', 'paving', 'the', 'way', 'for', 'abundance', 'of', 'efficient', 'catalytic', 'sites', 'at', 'the', 'edges', 'of', 'magnetic', 'graphene', 'islands', 'covering', 'more', 'b', 'sites', 'than', 'n', 'sites', 'accordingly', 'as', 'an', 'alternate', 'to', 'precious', 'metals', 'for', 'electrodes', 'we', 'propose', 'a', 'class', 'of', 'graphenehbn', 'hybrids', 'with', 'lattices', 'of', 'magnetic', 'graphene', 'islands', 'embedded', 'in', 'hbn', 'which', 'can', 'be', 'metallic']]
|
[-0.12532003919333715, 0.19165730491302024, 0.0387877485955651, 0.012296914018092131, 0.01899284690405161, -0.2043138849535716, 0.14013020381682903, 0.4629032641238473, -0.23427433374128925, -0.33032776498210975, -0.021858693459053512, -0.32597197267357897, -0.11524989802351385, 0.16403851975215875, 0.04701270164652752, -0.048364234770936564, 0.012507125460843736, -0.041127240354329804, -0.031813005137721166, -0.27226111964772354, 0.22521519197324583, 0.07626205058803803, 0.2805953728417537, 0.0913951277800131, -0.021948516927482453, -0.06079750013371271, 0.10852898351897701, 0.04970864417073901, -0.1432869865705612, 0.08722491073339138, 0.2411372702278395, -0.08951401500099519, 0.21921759730952123, -0.494460459083262, -0.17725400933145966, 0.05338764511634854, 0.17308292191337524, 0.15148564731125, -0.0936556989530136, -0.22389907530020256, 0.1001716280212633, -0.1204109529189114, -0.10701451726176354, -0.04423459682072701, 0.09579598441270283, -0.0050958709091040175, -0.24439794333481688, 0.050181220777371735, 0.05311094770808226, 0.08649480765855415, -0.058470560355508565, -0.17291505229145912, -0.14211489137938466, 0.07726287513620755, 0.03808221404401748, 0.05865980099582117, 0.19165005671221608, -0.06825131819912802, -0.08383547798743712, 0.401164931687792, -0.011937444235458032, -0.08853343384120854, 0.234478981678105, -0.19719305638925033, -0.11408808623075825, 0.14626237947727064, 0.1256754246784707, 0.1089826835347729, -0.14546516709655574, 0.07090532924238939, -0.019694583217822328, 0.1312899507826527, 0.1269034831342022, 0.08462966262927711, 0.2614597215745669, 0.1996586058924449, 0.11238156083418842, 0.1404416950874583, -0.08659845795624044, -0.0027380091702112284, -0.1572385542484234, -0.22401935875082934, -0.20269580975444032, 0.08916462743370449, -0.06911891056002276, -0.2145012044755055, 0.35256869775146166, 0.09892875475086584, 0.18432440535476768, -0.08837373058502863, 0.17007483116319197, 0.04586725553166574, 0.13450443308212628, 0.031006762017796927, 0.21832062379446432, 0.14305272304360886, 0.0937372269215126, -0.18972804832994627, 0.10062102063783859, 0.018855808283283797]
|
1,803.06999
|
Characterization of High Purity Germanium Point Contact Detectors with
Low Net Impurity Concentration
|
High Purity germanium point-contact detectors have low energy thresholds and
excellent energy resolution over a wide energy range, and are thus widely used
in nuclear and particle physics. In rare event searches, such as neutrinoless
double beta decay, the point-contact geometry is of particular importance since
it allows for pulse-shape discrimination, and therefore for a significant
background reduction. In this paper we investigate the pulse-shape
discrimination performance of ultra-high purity germanium point contact
detectors. It is demonstrated that a minimal net impurity concentration is
required to meet the pulse-shape performance requirements.
|
physics.ins-det
|
high purity germanium pointcontact detectors have low energy thresholds and excellent energy resolution over a wide energy range and are thus widely used in nuclear and particle physics in rare event searches such as neutrinoless double beta decay the pointcontact geometry is of particular importance since it allows for pulseshape discrimination and therefore for a significant background reduction in this paper we investigate the pulseshape discrimination performance of ultrahigh purity germanium point contact detectors it is demonstrated that a minimal net impurity concentration is required to meet the pulseshape performance requirements
|
[['high', 'purity', 'germanium', 'pointcontact', 'detectors', 'have', 'low', 'energy', 'thresholds', 'and', 'excellent', 'energy', 'resolution', 'over', 'a', 'wide', 'energy', 'range', 'and', 'are', 'thus', 'widely', 'used', 'in', 'nuclear', 'and', 'particle', 'physics', 'in', 'rare', 'event', 'searches', 'such', 'as', 'neutrinoless', 'double', 'beta', 'decay', 'the', 'pointcontact', 'geometry', 'is', 'of', 'particular', 'importance', 'since', 'it', 'allows', 'for', 'pulseshape', 'discrimination', 'and', 'therefore', 'for', 'a', 'significant', 'background', 'reduction', 'in', 'this', 'paper', 'we', 'investigate', 'the', 'pulseshape', 'discrimination', 'performance', 'of', 'ultrahigh', 'purity', 'germanium', 'point', 'contact', 'detectors', 'it', 'is', 'demonstrated', 'that', 'a', 'minimal', 'net', 'impurity', 'concentration', 'is', 'required', 'to', 'meet', 'the', 'pulseshape', 'performance', 'requirements']]
|
[-0.028404396058029528, 0.16403196104239304, -0.06259826137326084, 0.12651102376620765, -0.006188387997898754, -0.18334028003532643, 0.03604111628182191, 0.3898353796749079, -0.1925303864569127, -0.39998615815580546, 0.04502707283053506, -0.32670901764128585, -0.04287280698030532, 0.22943642149694715, -0.036742382391181945, 0.13293807092890308, 0.10033417518179004, 0.02353025599290709, -0.10519091065609726, -0.19826866675086402, 0.21948128967331007, 0.21882570518569633, 0.3768495283611528, 0.12481469223992182, 0.11967158790391225, 0.03230910280279324, 0.001228048256342555, -0.013601085580476038, -0.13710124915822955, 0.02025036183237047, 0.35034982872369524, 0.0823454731502212, 0.17172521819452663, -0.36729107827848784, -0.20541186064768296, 0.16021518431767656, 0.10891112751214878, 0.030120359041285447, -0.16636726433401006, -0.23009007327913583, 0.11907672073569271, -0.21543554235812645, -0.06390233114771135, -0.0765274928621743, -0.025800194591283798, 0.04196510642030082, -0.23853281678652372, 0.0344159776692862, -0.0029367106444724315, -0.0011802449372116026, -0.0027185984954985042, -0.13714974859197224, 0.08099901330258165, 0.06245975073038058, 0.021676013647875452, -0.03664391350057385, 0.19788979807008916, -0.16240194466753075, -0.09140345402021002, 0.30757323533787834, -0.03613808883000984, -0.15986846450327352, 0.212882135657, -0.1726398299867799, -0.0962579747365153, 0.22319476650311396, 0.1454311446286738, 0.06872761297131796, -0.18663225702654856, 0.11724063102187907, 0.09542039587356888, 0.21905815945381737, 0.10980648006015754, 0.10947692022239278, 0.2212310521044656, 0.2848455283105128, 0.09327240218664264, 0.08432354894466698, -0.23149955850657444, 0.015431233326095965, -0.2953059322477042, -0.2295024320790237, -0.15908151039096352, 0.05796242848161485, -0.060896936271232195, -0.16179779284521117, 0.4087134098511312, 0.09733136628682797, 0.11598266298872428, -0.05818574934440491, 0.27685493707738734, 0.07619476632424886, 0.030705456053940476, -0.05968093186371274, 0.31302936504605217, 0.158408200102193, 0.08767929486802441, -0.24427318098637593, 0.0480899274717648, -0.04325778543396474]
|
1,803.07
|
Generalized Rich-Club Ordering in Networks
|
Rich-club ordering refers to the tendency of nodes with a high degree to be
more interconnected than expected. In this paper we consider the concept of
rich-club ordering when generalized to structural measures that differ from the
node degree and to non-structural measures (i.e. to node metadata). The
differences in considering rich-club ordering (RCO) with respect to both
structural and non-structural measures is then discussed in terms of employed
coefficients and of appropriate null models (link rewiring vs metadata
reshuffling). Once a framework for the evaluation of generalized rich-club
ordering (GRCO) is defined, we investigate such a phenomenon in real networks
provided with node metadata. By considering different notions of node richness,
we compare structural and non-structural rich-club ordering, observing how
external information about the network nodes is able to validate the presence
of rich-clubs in networked systems.
|
physics.soc-ph cs.SI
|
richclub ordering refers to the tendency of nodes with a high degree to be more interconnected than expected in this paper we consider the concept of richclub ordering when generalized to structural measures that differ from the node degree and to nonstructural measures ie to node metadata the differences in considering richclub ordering rco with respect to both structural and nonstructural measures is then discussed in terms of employed coefficients and of appropriate null models link rewiring vs metadata reshuffling once a framework for the evaluation of generalized richclub ordering grco is defined we investigate such a phenomenon in real networks provided with node metadata by considering different notions of node richness we compare structural and nonstructural richclub ordering observing how external information about the network nodes is able to validate the presence of richclubs in networked systems
|
[['richclub', 'ordering', 'refers', 'to', 'the', 'tendency', 'of', 'nodes', 'with', 'a', 'high', 'degree', 'to', 'be', 'more', 'interconnected', 'than', 'expected', 'in', 'this', 'paper', 'we', 'consider', 'the', 'concept', 'of', 'richclub', 'ordering', 'when', 'generalized', 'to', 'structural', 'measures', 'that', 'differ', 'from', 'the', 'node', 'degree', 'and', 'to', 'nonstructural', 'measures', 'ie', 'to', 'node', 'metadata', 'the', 'differences', 'in', 'considering', 'richclub', 'ordering', 'rco', 'with', 'respect', 'to', 'both', 'structural', 'and', 'nonstructural', 'measures', 'is', 'then', 'discussed', 'in', 'terms', 'of', 'employed', 'coefficients', 'and', 'of', 'appropriate', 'null', 'models', 'link', 'rewiring', 'vs', 'metadata', 'reshuffling', 'once', 'a', 'framework', 'for', 'the', 'evaluation', 'of', 'generalized', 'richclub', 'ordering', 'grco', 'is', 'defined', 'we', 'investigate', 'such', 'a', 'phenomenon', 'in', 'real', 'networks', 'provided', 'with', 'node', 'metadata', 'by', 'considering', 'different', 'notions', 'of', 'node', 'richness', 'we', 'compare', 'structural', 'and', 'nonstructural', 'richclub', 'ordering', 'observing', 'how', 'external', 'information', 'about', 'the', 'network', 'nodes', 'is', 'able', 'to', 'validate', 'the', 'presence', 'of', 'richclubs', 'in', 'networked', 'systems']]
|
[-0.16894270111452384, 0.08734142436119526, -0.017663207718346646, 0.07682689189728674, -0.09241800788162358, -0.1332029103524173, 0.10711011812310207, 0.39099216115647467, -0.3079538341557634, -0.3146398012594664, 0.028497913422947073, -0.32516905316489114, -0.2169186553877333, 0.047700495954115366, -0.06288454985411406, 0.012219828195815933, 0.023308860677955807, 0.09907961956502033, -0.051831180562157235, -0.22937000384453035, 0.3555957985960919, 0.07973674611307417, 0.31067076314618625, 0.0639944086370119, 0.10625269786491433, 0.00725221866066905, -0.030257574896719576, 0.10957435965858589, -0.11768132269887997, 0.14023847141357113, 0.2809483337943306, 0.16978603425314245, 0.25351143257179554, -0.3856156462857473, -0.21451482038432057, 0.13774338915296222, 0.1051044861205678, 0.04811558976728955, 0.04810372710789375, -0.3036519405229584, 0.15360467711908984, -0.1728864454091071, -0.09614168999352209, -0.09193019092545264, -0.01600214436083384, 0.08542928603761223, -0.2526448615759179, 0.08232952672583253, 0.04751563608263403, 0.13612523881475563, -0.030504298409905987, -0.07239695553046961, -0.05963046386487026, 0.13580039905428892, 0.02921271026286337, 0.0032395610739342005, 0.11548699198655137, -0.113588356505742, -0.1562748862720648, 0.3959980633082813, 0.0048601058900374855, -0.2081280384229393, 0.1892198098492741, -0.11585140096671555, -0.160630232381189, 0.04872786686958178, 0.17470135731096176, 0.02694648551835638, -0.17370718322659293, -0.03153953803838163, 0.00175070745256338, 0.17536522378213704, 0.0798648425269926, 0.06266152798333138, 0.14009554064967603, 0.17503301498135956, 0.10971142938765495, 0.1690119841444792, -0.04291437379340979, -0.12635998873978996, -0.19313058184554288, -0.13769313765932684, -0.19826738278556993, -0.010333417999166726, -0.17107387222105003, -0.13622043074608065, 0.42209849287620815, 0.1710610590989877, 0.22006157360822504, 0.04641893203201555, 0.22796557794166458, 0.061502558533507196, 0.06409986403119494, 0.07091105460405242, 0.12866909215159283, 0.12475629036729831, 0.09948107935623199, -0.18101357600982368, 0.19406288129655455, 0.01465759838870524]
|
1,803.07001
|
A short survey on Newton polytopes, tropical geometry and ring of
conditions of algebraic torus
|
The purpose of this note is to give an exposition of some interesting
combinatorics and convex geometry concepts that appear in algebraic geometry in
relation to counting the number of solutions of a system of polynomial
equations in several variables over complex numbers. The exposition is aimed
for a general audience in mathematics and we hope to be accessible to
undergraduate as well as advance high school students. The topics discussed
belong to relatively new, and closely related branches of algebraic geometry
which are usually referred to as tropical geometry and toric geometry. These
areas make connections between the study of algebra and geometry of polynomials
and the combinatorial and convex geometric study of piecewise linear functions.
The main results discussed in this note are descriptions of the so-called "ring
of conditions" of algebraic torus.
|
math.AG
|
the purpose of this note is to give an exposition of some interesting combinatorics and convex geometry concepts that appear in algebraic geometry in relation to counting the number of solutions of a system of polynomial equations in several variables over complex numbers the exposition is aimed for a general audience in mathematics and we hope to be accessible to undergraduate as well as advance high school students the topics discussed belong to relatively new and closely related branches of algebraic geometry which are usually referred to as tropical geometry and toric geometry these areas make connections between the study of algebra and geometry of polynomials and the combinatorial and convex geometric study of piecewise linear functions the main results discussed in this note are descriptions of the socalled ring of conditions of algebraic torus
|
[['the', 'purpose', 'of', 'this', 'note', 'is', 'to', 'give', 'an', 'exposition', 'of', 'some', 'interesting', 'combinatorics', 'and', 'convex', 'geometry', 'concepts', 'that', 'appear', 'in', 'algebraic', 'geometry', 'in', 'relation', 'to', 'counting', 'the', 'number', 'of', 'solutions', 'of', 'a', 'system', 'of', 'polynomial', 'equations', 'in', 'several', 'variables', 'over', 'complex', 'numbers', 'the', 'exposition', 'is', 'aimed', 'for', 'a', 'general', 'audience', 'in', 'mathematics', 'and', 'we', 'hope', 'to', 'be', 'accessible', 'to', 'undergraduate', 'as', 'well', 'as', 'advance', 'high', 'school', 'students', 'the', 'topics', 'discussed', 'belong', 'to', 'relatively', 'new', 'and', 'closely', 'related', 'branches', 'of', 'algebraic', 'geometry', 'which', 'are', 'usually', 'referred', 'to', 'as', 'tropical', 'geometry', 'and', 'toric', 'geometry', 'these', 'areas', 'make', 'connections', 'between', 'the', 'study', 'of', 'algebra', 'and', 'geometry', 'of', 'polynomials', 'and', 'the', 'combinatorial', 'and', 'convex', 'geometric', 'study', 'of', 'piecewise', 'linear', 'functions', 'the', 'main', 'results', 'discussed', 'in', 'this', 'note', 'are', 'descriptions', 'of', 'the', 'socalled', 'ring', 'of', 'conditions', 'of', 'algebraic', 'torus']]
|
[-0.10771021637893109, 0.05850909344638543, -0.1119017379986838, 0.1225844064761919, -0.1424326933696176, -0.13195697894250905, -0.026212109597744764, 0.2990978286981031, -0.3224845933417479, -0.3033630330908906, 0.14525693714256502, -0.22560509376710763, -0.21835644028528972, 0.2365581204769788, -0.17067263912133596, -0.003282812368814592, 0.0020208591552175305, 0.042297171506409846, -0.09289756534805443, -0.28050310789710947, 0.3623260106201525, 0.034698255849933184, 0.20900260156227482, 0.06681667157978087, 0.07957311784503636, -0.0015516102727916505, -0.06233256627909011, 0.0407419255822552, -0.15334091572359385, 0.1706898511904809, 0.3923197983591645, 0.14349985826001674, 0.23086373444163688, -0.43271862930721705, -0.11074230585040318, 0.06798895862367418, 0.10861971985065827, 0.07907705112377665, -0.0140243383952313, -0.22848003760532096, 0.030065033967710205, -0.12389887231229632, -0.17572719159458453, -0.06151026206918889, 0.026838412153086178, 0.08196074834300413, -0.16690472329242362, -0.018546660472121505, 0.09113648887809918, 0.1499050149694085, -0.015391731593343947, -0.11984804160116862, 0.015100791339797002, 0.08509104321193364, 0.04907898753364053, 0.02847744954784435, 0.0691447775017608, -0.13295160059782643, -0.12703493084862, 0.3812083997453252, 0.041795652307983905, -0.23019053053662733, 0.2146416147618934, -0.16165692424574107, -0.15812577818589355, 0.10020103390432067, 0.20967104333901296, 0.14316997366301992, -0.12185855517508808, 0.11733048689353315, -0.06964661974321913, 0.08396509480490177, 0.08461726397551872, 0.0436743372658923, 0.19157901420085519, 0.10076540412243318, 0.0486221414027063, 0.16912668976605078, 0.038763205707073214, -0.14857907747090968, -0.3612033722439298, -0.16816997504965575, -0.145272936699567, 0.06469414959213247, -0.06953022068083993, -0.19097087804090093, 0.42497807599742105, 0.09903709069584254, 0.18313927433832927, 0.04558524911667013, 0.2307839857414365, 0.07125695853200914, -0.0026043036262746212, 0.029187516426598583, 0.16139654803921952, 0.23862429752394004, 0.09024536298605165, -0.12413616023129886, 0.00555026050682904, 0.11144044969092917]
|
1,803.07002
|
Auslander-Reiten $(d+2)$-angles in subcategories and a $(d+2)$-angulated
generalisation of a theorem by Br\"uning
|
Let $\Phi$ be a finite dimensional algebra over an algebraically closed field
$k$ and assume gldim$\,\Phi\leq d$, for some fixed positive integer $d$. For
$d=1$, Br\"uning proved that there is a bijection between the wide
subcategories of the abelian category mod$\,\Phi$ and those of the triangulated
category $\mathcal{D}^b(\text{mod}\Phi)$. Moreover, for a suitable triangulated
category $\mathcal{M}$, J{\o}rgensen gave a description of Auslander-Reiten
triangles in the extension closed subcategories of $\mathcal{M}$.
In this paper, we generalise these results for $d$-abelian and
$(d+2)$-angulated categories, where kernels and cokernels are replaced by
complexes of $d+1$ objects and triangles are replaced by complexes of $d+2$
objects. The categories are obtained as follows: if $\mathcal{F}\subseteq
\text{mod} \Phi$ is a $d$-cluster tilting subcategory, consider
$\overline{\mathcal{F}}:=\text{add} \{\Sigma^{id}\mathcal{F}\mid i\in\mathbb{Z}
\}\subseteq \mathcal{D}^b(\text{mod}\Phi)$. Then $\mathcal{F}$ is $d$-abelian
and plays the role of a higher mod$\,\Phi$ having for higher derived category
the $(d+2)$-angulated category $\overline{\mathcal{F}}$.
|
math.RT
|
let phi be a finite dimensional algebra over an algebraically closed field k and assume gldimphileq d for some fixed positive integer d for d1 bruning proved that there is a bijection between the wide subcategories of the abelian category modphi and those of the triangulated category mathcaldbtextmodphi moreover for a suitable triangulated category mathcalm jorgensen gave a description of auslanderreiten triangles in the extension closed subcategories of mathcalm in this paper we generalise these results for dabelian and d2angulated categories where kernels and cokernels are replaced by complexes of d1 objects and triangles are replaced by complexes of d2 objects the categories are obtained as follows if mathcalfsubseteq textmod phi is a dcluster tilting subcategory consider overlinemathcalftextadd sigmaidmathcalfmid iinmathbbz subseteq mathcaldbtextmodphi then mathcalf is dabelian and plays the role of a higher modphi having for higher derived category the d2angulated category overlinemathcalf
|
[['let', 'phi', 'be', 'a', 'finite', 'dimensional', 'algebra', 'over', 'an', 'algebraically', 'closed', 'field', 'k', 'and', 'assume', 'gldimphileq', 'd', 'for', 'some', 'fixed', 'positive', 'integer', 'd', 'for', 'd1', 'bruning', 'proved', 'that', 'there', 'is', 'a', 'bijection', 'between', 'the', 'wide', 'subcategories', 'of', 'the', 'abelian', 'category', 'modphi', 'and', 'those', 'of', 'the', 'triangulated', 'category', 'mathcaldbtextmodphi', 'moreover', 'for', 'a', 'suitable', 'triangulated', 'category', 'mathcalm', 'jorgensen', 'gave', 'a', 'description', 'of', 'auslanderreiten', 'triangles', 'in', 'the', 'extension', 'closed', 'subcategories', 'of', 'mathcalm', 'in', 'this', 'paper', 'we', 'generalise', 'these', 'results', 'for', 'dabelian', 'and', 'd2angulated', 'categories', 'where', 'kernels', 'and', 'cokernels', 'are', 'replaced', 'by', 'complexes', 'of', 'd1', 'objects', 'and', 'triangles', 'are', 'replaced', 'by', 'complexes', 'of', 'd2', 'objects', 'the', 'categories', 'are', 'obtained', 'as', 'follows', 'if', 'mathcalfsubseteq', 'textmod', 'phi', 'is', 'a', 'dcluster', 'tilting', 'subcategory', 'consider', 'overlinemathcalftextadd', 'sigmaidmathcalfmid', 'iinmathbbz', 'subseteq', 'mathcaldbtextmodphi', 'then', 'mathcalf', 'is', 'dabelian', 'and', 'plays', 'the', 'role', 'of', 'a', 'higher', 'modphi', 'having', 'for', 'higher', 'derived', 'category', 'the', 'd2angulated', 'category', 'overlinemathcalf']]
|
[-0.1806344701770555, 0.08697585632638678, -0.025281245278677453, 0.07798270152761015, -0.04691631828296792, -0.19468980895493318, -0.06012311783291537, 0.376016995890273, -0.33759487747663147, -0.17949279964798026, 0.05374345966545796, -0.2386350632990124, -0.06864817468104539, 0.15973181585884758, -0.187433291307685, -0.12310108184745466, 0.07993272100920203, 0.12978574897473058, -0.012252117448520882, -0.2599623309948516, 0.437282390287146, -0.08781723262811149, 0.1961745700419501, 0.029654635771833086, 0.11979532725419159, 0.0056886761380290545, 0.025904842736889366, 0.08601477156582944, -0.1915743788612114, 0.13243754134271984, 0.33899623125239653, 0.08340813186778515, 0.20028872375152315, -0.32444509458555665, -0.08618863318654432, 0.18998994663771657, 0.15148552735853527, -0.02556776424386987, -0.027093343798898988, -0.30249293580375336, 0.17676485495607333, -0.2062350813437391, -0.09030506863362259, -0.048188383568561186, 0.18932781306147162, 0.0010581880359462014, -0.32654026331104063, -0.03656117360935443, 0.14635737258940934, 0.16788902216832394, -0.09823697222293251, -0.15202357324392154, -0.09525458439839658, 0.07439423007200714, -0.08985832325717504, 0.07687291819257316, 0.0743371367626996, -0.11352410241514142, -0.10257812954002508, 0.3479575653319006, -0.046344246487650606, -0.2377702156978625, 0.1336411484223963, -0.14955242411061018, -0.12954756794152436, 0.1388593038475072, -0.01293490424890209, 0.18852132576069347, -0.01537396707895419, 0.24828239663555804, -0.1862790301338666, 0.048600984395792086, 0.14459202858377937, 0.02737045154078967, 0.15619254706910363, 0.09989652006770484, 0.022111335612350593, 0.17696127519442664, 0.011154618914480562, -0.0011608385963848343, -0.3660497794272723, -0.18082429827622104, -0.08038553864419185, 0.14302901948664198, -0.11875988016944138, -0.15771711009330358, 0.3070161862316093, 0.05548231595290687, 0.19958947240202515, 0.16840488197350945, 0.15881716857353848, 0.007800852334023349, 0.04433700170160996, 0.05822653473113422, 0.08421256838612155, 0.2546454829853718, -0.04817619311054134, -0.054662844338626775, -0.021732043430071186, 0.22108494582827445]
|
1,803.07003
|
Efficient algorithm to compute the second Chern number in four
dimensional systems
|
Topological insulators are exotic material that possess conducting surface
states protected by the topology of the system. They can be classified in terms
of their properties under discrete symmetries and are characterized by
topological invariants. The latter has been measured experimentally for several
models in one, two and three dimensions in both condensed matter and quantum
simulation platforms. The recent progress in quantum simulation opens the road
to the simulation of higher dimensional Hamiltonians and in particular of the
4D quantum Hall effect. These systems are characterized by the second Chern
number, a topological invariant that appears in the quantization of the
transverse conductivity for the non-linear response to both external magnetic
and electric fields. This quantity cannot always be computed analytically and
there is therefore a need of an algorithm to compute it numerically. In this
work, we propose an efficient algorithm to compute the second Chern number in
4D systems. We construct the algorithm with the help of lattice gauge theory
and discuss the convergence to the continuous gauge theory. We benchmark the
algorithm on several relevant models, including the 4D Dirac Hamiltonian and
the 4D quantum Hall effect and verify numerically its rapid convergence.
|
cond-mat.quant-gas cond-mat.mes-hall cond-mat.str-el quant-ph
|
topological insulators are exotic material that possess conducting surface states protected by the topology of the system they can be classified in terms of their properties under discrete symmetries and are characterized by topological invariants the latter has been measured experimentally for several models in one two and three dimensions in both condensed matter and quantum simulation platforms the recent progress in quantum simulation opens the road to the simulation of higher dimensional hamiltonians and in particular of the 4d quantum hall effect these systems are characterized by the second chern number a topological invariant that appears in the quantization of the transverse conductivity for the nonlinear response to both external magnetic and electric fields this quantity cannot always be computed analytically and there is therefore a need of an algorithm to compute it numerically in this work we propose an efficient algorithm to compute the second chern number in 4d systems we construct the algorithm with the help of lattice gauge theory and discuss the convergence to the continuous gauge theory we benchmark the algorithm on several relevant models including the 4d dirac hamiltonian and the 4d quantum hall effect and verify numerically its rapid convergence
|
[['topological', 'insulators', 'are', 'exotic', 'material', 'that', 'possess', 'conducting', 'surface', 'states', 'protected', 'by', 'the', 'topology', 'of', 'the', 'system', 'they', 'can', 'be', 'classified', 'in', 'terms', 'of', 'their', 'properties', 'under', 'discrete', 'symmetries', 'and', 'are', 'characterized', 'by', 'topological', 'invariants', 'the', 'latter', 'has', 'been', 'measured', 'experimentally', 'for', 'several', 'models', 'in', 'one', 'two', 'and', 'three', 'dimensions', 'in', 'both', 'condensed', 'matter', 'and', 'quantum', 'simulation', 'platforms', 'the', 'recent', 'progress', 'in', 'quantum', 'simulation', 'opens', 'the', 'road', 'to', 'the', 'simulation', 'of', 'higher', 'dimensional', 'hamiltonians', 'and', 'in', 'particular', 'of', 'the', '4d', 'quantum', 'hall', 'effect', 'these', 'systems', 'are', 'characterized', 'by', 'the', 'second', 'chern', 'number', 'a', 'topological', 'invariant', 'that', 'appears', 'in', 'the', 'quantization', 'of', 'the', 'transverse', 'conductivity', 'for', 'the', 'nonlinear', 'response', 'to', 'both', 'external', 'magnetic', 'and', 'electric', 'fields', 'this', 'quantity', 'can', 'not', 'always', 'be', 'computed', 'analytically', 'and', 'there', 'is', 'therefore', 'a', 'need', 'of', 'an', 'algorithm', 'to', 'compute', 'it', 'numerically', 'in', 'this', 'work', 'we', 'propose', 'an', 'efficient', 'algorithm', 'to', 'compute', 'the', 'second', 'chern', 'number', 'in', '4d', 'systems', 'we', 'construct', 'the', 'algorithm', 'with', 'the', 'help', 'of', 'lattice', 'gauge', 'theory', 'and', 'discuss', 'the', 'convergence', 'to', 'the', 'continuous', 'gauge', 'theory', 'we', 'benchmark', 'the', 'algorithm', 'on', 'several', 'relevant', 'models', 'including', 'the', '4d', 'dirac', 'hamiltonian', 'and', 'the', '4d', 'quantum', 'hall', 'effect', 'and', 'verify', 'numerically', 'its', 'rapid', 'convergence']]
|
[-0.15684596129758943, 0.18642599294752923, -0.0755085216004947, 0.05403620639470208, -0.025830255863680082, -0.14622311891677478, -0.010294013025210888, 0.37203909726719364, -0.25700625311818465, -0.3188393650472992, 0.07636464877416277, -0.25835628403677613, -0.2115674386855751, 0.2050513142879789, -0.02550836168041434, 0.11628733381524334, -0.027013877068053593, 0.016794748104534893, -0.09107045466233177, -0.2893262265839219, 0.30725094076302467, -0.0017307466436930076, 0.2823703231047745, 0.06732229623006365, 0.058688529970528876, -0.036580158062420334, 0.028144820530974127, 0.06013747813436438, -0.11566072065217686, 0.11276290171416335, 0.23564872419570526, 0.01992647018932709, 0.19680084697337766, -0.44253834283374477, -0.21176713548431342, 0.07186366129675974, 0.1234217320093791, 0.1558636791152748, -0.05837811836314322, -0.31410009767730823, 0.10001276237796052, -0.17851690071131657, -0.11913623196435058, -0.15864594249888805, -0.0021796591810392912, -0.056683082793218396, -0.2071183101542181, 0.04623704739479405, 0.02709962004816837, 0.06440209457004029, -0.06746693655455749, -0.05514444487646805, -0.06064191109952376, 0.12194034537168766, 0.0532752470398459, 3.268651081004528e-05, 0.08271607178300995, -0.17081513974364793, -0.18586912977443348, 0.4087897597840338, -0.02823384955638286, -0.23514081089348166, 0.19152235347634144, -0.12915267793678048, -0.12281270067423883, 0.11076725501393091, 0.16075203062100996, 0.13003513831386548, -0.09858933578932075, 0.1292030082829179, -0.024283535087086035, 0.10017331375216011, -0.006160253346098041, 0.06972155498453614, 0.23084180138657115, 0.10939932624266173, 0.05961037219520846, 0.16198392764187766, -0.06128216108761145, -0.11494817871793239, -0.2875059513337534, -0.20369024439761885, -0.22009930582105586, 0.060376928748890425, -0.0591370893231178, -0.16911971283079397, 0.4261519827884669, 0.16762378448567522, 0.16095963131278904, 0.0048163749696216495, 0.27154381898692764, 0.15126590485534055, 0.046944790219916314, 0.06537721744936073, 0.24084704512297506, 0.1486542921341636, 0.08875990581623457, -0.25783835664406807, 0.005516916820944071, 0.09268824437708416]
|
1,803.07004
|
Capturing photoelectron motion with guiding fictitious particles
|
Photoelectron momentum distributions (PMDs) from atoms and molecules undergo
qualitative changes as laser parameters are varied. We present a model to
interpret the shape of the PMDs. The electron's motion is guided by a
fictitious particle in our model, clearly characterizing two distinct dynamical
behaviors: direct ionization and rescattering. As laser ellipticity is varied,
our model reproduces the bifurcation in the PMDs seen in experiments.
|
nlin.CD physics.atom-ph
|
photoelectron momentum distributions pmds from atoms and molecules undergo qualitative changes as laser parameters are varied we present a model to interpret the shape of the pmds the electrons motion is guided by a fictitious particle in our model clearly characterizing two distinct dynamical behaviors direct ionization and rescattering as laser ellipticity is varied our model reproduces the bifurcation in the pmds seen in experiments
|
[['photoelectron', 'momentum', 'distributions', 'pmds', 'from', 'atoms', 'and', 'molecules', 'undergo', 'qualitative', 'changes', 'as', 'laser', 'parameters', 'are', 'varied', 'we', 'present', 'a', 'model', 'to', 'interpret', 'the', 'shape', 'of', 'the', 'pmds', 'the', 'electrons', 'motion', 'is', 'guided', 'by', 'a', 'fictitious', 'particle', 'in', 'our', 'model', 'clearly', 'characterizing', 'two', 'distinct', 'dynamical', 'behaviors', 'direct', 'ionization', 'and', 'rescattering', 'as', 'laser', 'ellipticity', 'is', 'varied', 'our', 'model', 'reproduces', 'the', 'bifurcation', 'in', 'the', 'pmds', 'seen', 'in', 'experiments']]
|
[-0.08033310758093229, 0.1935783612362754, -0.13512651017652108, 0.09856992999020105, 0.0036083423604185766, -0.11173043481181734, -0.005887385744314928, 0.41796111991772283, -0.27099963658704207, -0.33189359123890216, -0.07153579147640042, -0.2996850991335053, -0.12817080615518184, 0.18425819842109026, -0.02010349235855616, 0.053001734886605006, 0.060938793721680456, -0.06612793184243716, -0.05105903134323084, -0.1163025826215744, 0.2679900541185187, 0.06431268415986918, 0.19905216835725767, 0.011397629403150998, 0.08388448882346543, 0.020049372781068088, 0.005770886718080594, -0.010411952364330108, -0.14457101724468746, 0.035479802426170166, 0.20789330411845675, 0.05264582755581404, 0.1754446880103877, -0.4152326671549907, -0.26115278247743845, 0.017599708816179862, 0.17283828276424454, 0.14688215986467323, -0.07464755231944414, -0.29048197217858757, -0.046305294922338085, -0.14021319757000758, -0.13201728624363357, -0.07805888052456654, 0.010598594777715895, 0.10968608540984301, -0.2854372279145397, 0.09080584071791516, 0.0526958079842958, 0.06783127976724734, -0.09382207832800654, -0.07270212398412136, -0.08099263994596326, 0.10290412299621564, 0.06819009282447111, 0.03953103307777872, 0.21796581367603862, -0.09609401579946279, -0.11585115624878269, 0.3952939592874967, -0.076255540873927, -0.16670394602518243, 0.18382298092429455, -0.17569645934093456, -0.08227577968858756, 0.19640216221316503, 0.1310902972920583, 0.13634599783959298, -0.10113088371088871, 0.01856649449775712, -0.05423288151908379, 0.19829379433336167, 0.09231194514566315, 0.018353840737388685, 0.199616404192952, 0.16143503971218776, -0.026140424336951514, 0.1531409751623869, -0.12166623612865805, -0.1453048510476947, -0.2941104711785626, -0.08469637517745678, -0.1858174426910969, -0.006167174202318375, -0.07990940648507183, -0.12979615869788597, 0.43572055898033657, 0.1366806600923435, 0.2688426768550506, -0.031225794109587486, 0.2808868952238789, 0.10840026127317777, 0.006982596236496018, -0.006553990823718218, 0.2671318448363588, 0.13814250776329293, 0.09861526884711706, -0.2742909831747126, 0.08581247036703504, 0.011964785107053243]
|
1,803.07005
|
Stochastic evolution equations with singular drift and gradient noise
via curvature and commutation conditions
|
We prove existence and uniqueness of solutions to a nonlinear stochastic
evolution equation on the $d$-dimensional torus with singular $p$-Laplace-type
or total variation flow-type drift with general sublinear doubling
nonlinearities and Gaussian gradient Stratonovich noise with divergence-free
coefficients. Assuming a weak defective commutator bound and a
curvature-dimension condition, the well-posedness result is obtained in a
stochastic variational inequality setup by using resolvent and Dirichlet form
methods and an approximative It\^{o}-formula.
|
math.AP math.FA math.PR
|
we prove existence and uniqueness of solutions to a nonlinear stochastic evolution equation on the ddimensional torus with singular plaplacetype or total variation flowtype drift with general sublinear doubling nonlinearities and gaussian gradient stratonovich noise with divergencefree coefficients assuming a weak defective commutator bound and a curvaturedimension condition the wellposedness result is obtained in a stochastic variational inequality setup by using resolvent and dirichlet form methods and an approximative itoformula
|
[['we', 'prove', 'existence', 'and', 'uniqueness', 'of', 'solutions', 'to', 'a', 'nonlinear', 'stochastic', 'evolution', 'equation', 'on', 'the', 'ddimensional', 'torus', 'with', 'singular', 'plaplacetype', 'or', 'total', 'variation', 'flowtype', 'drift', 'with', 'general', 'sublinear', 'doubling', 'nonlinearities', 'and', 'gaussian', 'gradient', 'stratonovich', 'noise', 'with', 'divergencefree', 'coefficients', 'assuming', 'a', 'weak', 'defective', 'commutator', 'bound', 'and', 'a', 'curvaturedimension', 'condition', 'the', 'wellposedness', 'result', 'is', 'obtained', 'in', 'a', 'stochastic', 'variational', 'inequality', 'setup', 'by', 'using', 'resolvent', 'and', 'dirichlet', 'form', 'methods', 'and', 'an', 'approximative', 'itoformula']]
|
[-0.14299419415655776, 0.04428300648388635, -0.08278975844302255, 0.08414835089891878, -0.1418765478403024, -0.17409005156461743, -0.01538825823345046, 0.28895781581303565, -0.31199444252727687, -0.1879688095220405, 0.14492600510888937, -0.27271984851635667, -0.13461526343261526, 0.14996414899866542, -0.09258344247970945, 0.13818233359632068, 0.08935769453289497, 0.0005073564572502737, -0.08016916536861032, -0.23365588370116724, 0.36143958725818043, -0.029879656421236585, 0.22226751094980948, -0.004253472761669453, 0.1768663976935373, -0.016710203458163618, 0.017573740151103422, 0.023443427395777428, -0.18832927910557043, 0.10551744335722449, 0.16359924885066415, 0.02804189989262301, 0.32777205684586713, -0.43576019200617855, -0.2227723359170815, 0.15065331803634763, 0.07715822895229592, 0.05242498433622329, -0.054213890770409744, -0.31354375880049623, 0.054226350396925554, -0.059837271526887795, -0.20288828539027684, -0.09467627046008904, -0.009295299460274586, 0.08650652811680314, -0.4055510840608158, 0.1993478546998855, 0.13254860834475013, 0.03742620412030838, -0.1672676082673496, -0.08806081270576334, -0.003817102009686979, -0.049841534963849445, 0.03656338530160703, 0.011184138032452514, 0.06127513867492477, -0.08000119693536797, -0.0899234381571844, 0.2645674074858265, -0.19716006968224395, -0.3309211703422277, 0.1308658298752878, -0.13432418194639942, -0.12293368007015923, 0.1060104641550477, 0.12822358366236955, 0.16047232330817243, -0.173555469504841, 0.16339147373936072, -0.06174228116330029, 0.11420255130750762, 0.13012713901158693, 0.010261163993677854, 0.005444119036521601, 0.08831919782349597, 0.22278091627294602, 0.129476689139678, -0.009392799718467437, -0.12562486644753296, -0.3669292698951735, -0.13210137624485904, -0.1712133718141611, 0.18914438997381838, -0.18392374951529916, -0.21487899587584147, 0.2814018429776627, 0.04210885285494336, 0.1585485393019474, 0.12188350649818819, 0.25524306745416875, 0.2250387551991836, -0.039033219852633236, 0.13959047645397915, 0.15981533844867532, 0.26594264981120935, 0.12803704992773524, -0.20477804946173253, 0.05332623775103602, 0.2106809532843476]
|
1,803.07006
|
Observations of one young and three middle-aged $\gamma$-ray pulsars
with the Gran Telescopio Canarias
|
We used the 10.4m Gran Telescopio Canarias to search for the optical
counterparts to four isolated $\gamma$-ray pulsars, all detected in the X-rays
by either \xmm\ or \chan\ but not yet in the optical. Three of them are
middle-aged pulsars -- PSR\, J1846+0919 (0.36 Myr), PSR\, J2055+2539 (1.2 Myr),
PSR\, J2043+2740 (1.2 Myr) -- and one, PSR\, J1907+0602, is a young pulsar
(19.5 kyr). For both PSR\, J1907+0602 and PSR\, J2055+2539 we found one object
close to the pulsar position. However, in both cases such an object cannot be a
viable candidate counterpart to the pulsar. For PSR\, J1907+0602, because it
would imply an anomalously red spectrum for the pulsar and for PSR\, J2055+2539
because the pulsar would be unrealistically bright ($r'=20.34\pm0.04$) for the
assumed distance and interstellar extinction. For PSR\, J1846+0919, we found no
object sufficiently close to the expected position to claim a possible
association, whereas for PSR\, J2043+2740 we confirm our previous findings that
the object nearest to the pulsar position is an unrelated field star. We used
our brightness limits ($g' \approx 27$), the first obtained with a
large-aperture telescope for both PSR\, J1846+0919 and PSR\, J2055+2539, to
constrain the optical emission properties of these pulsars and investigate the
presence of spectral turnovers at low energies in their multi-wavelength
spectra.
|
astro-ph.HE
|
we used the 104m gran telescopio canarias to search for the optical counterparts to four isolated gammaray pulsars all detected in the xrays by either xmm or chan but not yet in the optical three of them are middleaged pulsars psr j18460919 036 myr psr j20552539 12 myr psr j20432740 12 myr and one psr j19070602 is a young pulsar 195 kyr for both psr j19070602 and psr j20552539 we found one object close to the pulsar position however in both cases such an object cannot be a viable candidate counterpart to the pulsar for psr j19070602 because it would imply an anomalously red spectrum for the pulsar and for psr j20552539 because the pulsar would be unrealistically bright r2034pm004 for the assumed distance and interstellar extinction for psr j18460919 we found no object sufficiently close to the expected position to claim a possible association whereas for psr j20432740 we confirm our previous findings that the object nearest to the pulsar position is an unrelated field star we used our brightness limits g approx 27 the first obtained with a largeaperture telescope for both psr j18460919 and psr j20552539 to constrain the optical emission properties of these pulsars and investigate the presence of spectral turnovers at low energies in their multiwavelength spectra
|
[['we', 'used', 'the', '104m', 'gran', 'telescopio', 'canarias', 'to', 'search', 'for', 'the', 'optical', 'counterparts', 'to', 'four', 'isolated', 'gammaray', 'pulsars', 'all', 'detected', 'in', 'the', 'xrays', 'by', 'either', 'xmm', 'or', 'chan', 'but', 'not', 'yet', 'in', 'the', 'optical', 'three', 'of', 'them', 'are', 'middleaged', 'pulsars', 'psr', 'j18460919', '036', 'myr', 'psr', 'j20552539', '12', 'myr', 'psr', 'j20432740', '12', 'myr', 'and', 'one', 'psr', 'j19070602', 'is', 'a', 'young', 'pulsar', '195', 'kyr', 'for', 'both', 'psr', 'j19070602', 'and', 'psr', 'j20552539', 'we', 'found', 'one', 'object', 'close', 'to', 'the', 'pulsar', 'position', 'however', 'in', 'both', 'cases', 'such', 'an', 'object', 'can', 'not', 'be', 'a', 'viable', 'candidate', 'counterpart', 'to', 'the', 'pulsar', 'for', 'psr', 'j19070602', 'because', 'it', 'would', 'imply', 'an', 'anomalously', 'red', 'spectrum', 'for', 'the', 'pulsar', 'and', 'for', 'psr', 'j20552539', 'because', 'the', 'pulsar', 'would', 'be', 'unrealistically', 'bright', 'r2034pm004', 'for', 'the', 'assumed', 'distance', 'and', 'interstellar', 'extinction', 'for', 'psr', 'j18460919', 'we', 'found', 'no', 'object', 'sufficiently', 'close', 'to', 'the', 'expected', 'position', 'to', 'claim', 'a', 'possible', 'association', 'whereas', 'for', 'psr', 'j20432740', 'we', 'confirm', 'our', 'previous', 'findings', 'that', 'the', 'object', 'nearest', 'to', 'the', 'pulsar', 'position', 'is', 'an', 'unrelated', 'field', 'star', 'we', 'used', 'our', 'brightness', 'limits', 'g', 'approx', '27', 'the', 'first', 'obtained', 'with', 'a', 'largeaperture', 'telescope', 'for', 'both', 'psr', 'j18460919', 'and', 'psr', 'j20552539', 'to', 'constrain', 'the', 'optical', 'emission', 'properties', 'of', 'these', 'pulsars', 'and', 'investigate', 'the', 'presence', 'of', 'spectral', 'turnovers', 'at', 'low', 'energies', 'in', 'their', 'multiwavelength', 'spectra']]
|
[-0.09420425565539912, 0.10957715805488988, -0.0741316581634752, 0.13941689272178337, -0.21080071219783453, -0.135494281917828, 0.08643440801413062, 0.4616977058807915, -0.15773949587612218, -0.34437288137433947, 0.0954259941925488, -0.31033854587838267, 0.00718124308689269, 0.2993778608594406, -0.04242000018492482, -0.043785813945468585, 0.13926075522146486, -0.025501198262165143, -0.0018285882776220908, -0.19828474966280343, 0.18530252916334233, 0.08365203675765649, 0.09853127529352622, -0.01703102779926135, 0.13450011703101172, -0.07750675340297299, 0.03122968661581289, -0.10275156252170213, -0.08013071304337228, 0.02413435887769392, 0.233745679441611, 0.08525106523069004, 0.12375723925322506, -0.3247483827718446, -0.17774588086440246, 0.10850318845466904, 0.18588106355405817, -0.059346682080155554, -0.012248873630871356, -0.3673785070027664, 0.11083676632344303, -0.2846121476322878, -0.2225066379815305, 0.09568855944605772, 0.09229319672515388, 0.04959024626400348, -0.15729143787263278, 0.07107494353703311, 0.0002332322474103421, 0.03333621313751517, -0.18496018718106602, -0.1222759615717772, 0.06570469879244349, 0.05035064840263177, 0.043502961841130734, 0.0958160881880003, 0.07230867157725371, -0.1325411256842034, -0.09806390248133608, 0.40983872651561815, -0.05151780699555463, 0.026396502606693725, 0.22074339630626985, -0.2605400051315368, -0.24519020626277505, 0.14872654494697685, 0.07343209864690302, 0.12637804566777117, -0.18009384322191044, -0.030861824496516317, -0.02503721840088783, 0.26202088739845975, 0.04512235991445915, 0.07164357148851093, 0.3501819842924031, 0.09426762668453245, 0.026030267243392167, 0.10238201238043641, -0.3579000672359812, 0.01922232461275032, -0.16541971592932725, -0.053726296076761944, -0.14586783147072155, 0.14610148428426945, -0.11706197901504259, -0.07545390316144616, 0.3421870587099308, 0.12473047720070682, 0.12447190008846656, 0.040137078507610086, 0.27316420137737263, 0.1275466379109893, 0.03747440189153905, 0.18578567635926926, 0.37462282122798124, 0.17280077295518428, 0.11455541934800458, -0.2277275990007801, 0.09622573853856972, -0.04501486212489599]
|
1,803.07007
|
Specifying and Analyzing Virtual Network Services Using Queuing Petri
Nets
|
For optimal placement and orchestration of network services, it is crucial
that their structure and semantics are specified clearly and comprehensively
and are available to an orchestrator. Existing specification approaches are
either ambiguous or miss important aspects regarding the behavior of virtual
network functions (VNFs) forming a service. We propose to formally and
unambiguously specify the behavior of these functions and services using
Queuing Petri Nets (QPNs). QPNs are an established method that allows to
express queuing, synchronization, stochastically distributed processing delays,
and changing traffic volume and characteristics at each VNF. With QPNs,
multiple VNFs can be connected to complete network services in any structure,
even specifying bidirectional network services containing loops.
We propose a tool-based workflow that supports the specification of network
services and the automatic generation of corresponding simulation code to
enable an in-depth analysis of their behavior and performance. In a case study,
we show how developers can benefit from analysis insights, e.g., to anticipate
the impact of different service configurations. We also discuss how management
and orchestration systems can benefit from our clear and comprehensive
specification approach and its extensive analysis possibilities, leading to
better placement of VNFs and improved Quality of Service.
|
cs.NI
|
for optimal placement and orchestration of network services it is crucial that their structure and semantics are specified clearly and comprehensively and are available to an orchestrator existing specification approaches are either ambiguous or miss important aspects regarding the behavior of virtual network functions vnfs forming a service we propose to formally and unambiguously specify the behavior of these functions and services using queuing petri nets qpns qpns are an established method that allows to express queuing synchronization stochastically distributed processing delays and changing traffic volume and characteristics at each vnf with qpns multiple vnfs can be connected to complete network services in any structure even specifying bidirectional network services containing loops we propose a toolbased workflow that supports the specification of network services and the automatic generation of corresponding simulation code to enable an indepth analysis of their behavior and performance in a case study we show how developers can benefit from analysis insights eg to anticipate the impact of different service configurations we also discuss how management and orchestration systems can benefit from our clear and comprehensive specification approach and its extensive analysis possibilities leading to better placement of vnfs and improved quality of service
|
[['for', 'optimal', 'placement', 'and', 'orchestration', 'of', 'network', 'services', 'it', 'is', 'crucial', 'that', 'their', 'structure', 'and', 'semantics', 'are', 'specified', 'clearly', 'and', 'comprehensively', 'and', 'are', 'available', 'to', 'an', 'orchestrator', 'existing', 'specification', 'approaches', 'are', 'either', 'ambiguous', 'or', 'miss', 'important', 'aspects', 'regarding', 'the', 'behavior', 'of', 'virtual', 'network', 'functions', 'vnfs', 'forming', 'a', 'service', 'we', 'propose', 'to', 'formally', 'and', 'unambiguously', 'specify', 'the', 'behavior', 'of', 'these', 'functions', 'and', 'services', 'using', 'queuing', 'petri', 'nets', 'qpns', 'qpns', 'are', 'an', 'established', 'method', 'that', 'allows', 'to', 'express', 'queuing', 'synchronization', 'stochastically', 'distributed', 'processing', 'delays', 'and', 'changing', 'traffic', 'volume', 'and', 'characteristics', 'at', 'each', 'vnf', 'with', 'qpns', 'multiple', 'vnfs', 'can', 'be', 'connected', 'to', 'complete', 'network', 'services', 'in', 'any', 'structure', 'even', 'specifying', 'bidirectional', 'network', 'services', 'containing', 'loops', 'we', 'propose', 'a', 'toolbased', 'workflow', 'that', 'supports', 'the', 'specification', 'of', 'network', 'services', 'and', 'the', 'automatic', 'generation', 'of', 'corresponding', 'simulation', 'code', 'to', 'enable', 'an', 'indepth', 'analysis', 'of', 'their', 'behavior', 'and', 'performance', 'in', 'a', 'case', 'study', 'we', 'show', 'how', 'developers', 'can', 'benefit', 'from', 'analysis', 'insights', 'eg', 'to', 'anticipate', 'the', 'impact', 'of', 'different', 'service', 'configurations', 'we', 'also', 'discuss', 'how', 'management', 'and', 'orchestration', 'systems', 'can', 'benefit', 'from', 'our', 'clear', 'and', 'comprehensive', 'specification', 'approach', 'and', 'its', 'extensive', 'analysis', 'possibilities', 'leading', 'to', 'better', 'placement', 'of', 'vnfs', 'and', 'improved', 'quality', 'of', 'service']]
|
[-0.17049621852105343, 0.008037624146944729, -0.06507537059774292, 0.06738741788126737, -0.10788227630859515, -0.17179703067628865, 0.11702047620290125, 0.4488319079982599, -0.27273491537065464, -0.32749847321756903, 0.10453955687790505, -0.2543691592492656, -0.17123528346206596, 0.16460230259040398, -0.09927926678683249, 0.07759999638561604, 0.0845242415171892, 0.00019472706318374365, -0.026390722517850736, -0.23646659968033207, 0.3012228474490165, 0.03582387394389979, 0.35230515636905535, 0.1017574618994802, 0.041143595328469416, 0.012110667279566908, -0.03440050377987968, -0.007333369536188237, -0.08382055861339875, 0.15349295133545163, 0.3142017299808127, 0.24999841724092206, 0.26619136961990125, -0.47560378209909965, -0.17807687770783295, 0.061302470686245086, 0.16765402507196184, 0.03541228279168836, 0.020823189254193023, -0.29966211580283714, 0.1164645741818955, -0.24509659486936244, -0.07884651967111578, -0.13137402144724003, -0.04246977596605187, 0.07896388778853027, -0.2706685683930524, -0.06142165928238147, 0.013375985470416053, 0.047439852107770096, -0.047694638121795134, -0.05535876006353351, -0.05872482823404167, 0.2356225674922299, 0.015024262817273966, -0.015961230119104088, 0.17091568870686213, -0.11062787242734871, -0.1656159157332903, 0.3724630684402729, 0.011338364228908786, -0.19119978932484152, 0.21005804799638952, -0.013399328399440132, -0.1805862197912473, 0.0889354683370164, 0.24576701260015824, 0.05960740538303348, -0.21793603037689638, -0.0030762312081666085, 0.020361189764149034, 0.18279989950150857, 0.041272688779961035, 0.05713745958980192, 0.21459817153704233, 0.23731935910672555, 0.07368917262824583, 0.14670456177820948, 0.0008848556801960402, -0.10653533007439017, -0.23257485642671102, -0.1412549601078298, -0.10169951256062022, -0.0021520248067040506, -0.10140917730310266, -0.1636104360317367, 0.38716346885876607, 0.19659197771789383, 0.12962848030215102, 0.11518286681393644, 0.3580217543790864, 0.05720330525584386, 0.08962606363055216, 0.13081891394485035, 0.10391991814305335, -0.022644605653048468, 0.17911143640437704, -0.1767573489660993, 0.13443800541489542, 0.009412440021054317]
|
1,803.07008
|
Asymmetric Ejecta of Cool Supergiants and Hypergiants in the Massive
Cluster Westerlund 1
|
We report new 5.5 GHz radio observations of the massive star cluster
Westerlund 1, taken by the Australia Telescope Compact Array, detecting nine of
the ten yellow hypergiants (YHGs) and red supergiants (RSGs) within the
cluster. Eight of nine sources are spatially resolved. The nebulae associated
with the YHGs Wd1-4a, -12a and -265 demonstrate a cometary morphology - the
first time this phenomenon has been observed for such stars. This structure is
also echoed in the ejecta of the RSGs Wd1-20 and -26; in each case the cometary
tails are directed away from the cluster core. The nebular emission around the
RSG Wd1-237 is less collimated than these systems but once again appears more
prominent in the hemisphere facing the cluster. Considered as a whole, the
nebular morphologies provide compelling evidence for sculpting via a physical
agent associated with Westerlund 1, such as a cluster wind.
|
astro-ph.SR astro-ph.GA
|
we report new 55 ghz radio observations of the massive star cluster westerlund 1 taken by the australia telescope compact array detecting nine of the ten yellow hypergiants yhgs and red supergiants rsgs within the cluster eight of nine sources are spatially resolved the nebulae associated with the yhgs wd14a 12a and 265 demonstrate a cometary morphology the first time this phenomenon has been observed for such stars this structure is also echoed in the ejecta of the rsgs wd120 and 26 in each case the cometary tails are directed away from the cluster core the nebular emission around the rsg wd1237 is less collimated than these systems but once again appears more prominent in the hemisphere facing the cluster considered as a whole the nebular morphologies provide compelling evidence for sculpting via a physical agent associated with westerlund 1 such as a cluster wind
|
[['we', 'report', 'new', '55', 'ghz', 'radio', 'observations', 'of', 'the', 'massive', 'star', 'cluster', 'westerlund', '1', 'taken', 'by', 'the', 'australia', 'telescope', 'compact', 'array', 'detecting', 'nine', 'of', 'the', 'ten', 'yellow', 'hypergiants', 'yhgs', 'and', 'red', 'supergiants', 'rsgs', 'within', 'the', 'cluster', 'eight', 'of', 'nine', 'sources', 'are', 'spatially', 'resolved', 'the', 'nebulae', 'associated', 'with', 'the', 'yhgs', 'wd14a', '12a', 'and', '265', 'demonstrate', 'a', 'cometary', 'morphology', 'the', 'first', 'time', 'this', 'phenomenon', 'has', 'been', 'observed', 'for', 'such', 'stars', 'this', 'structure', 'is', 'also', 'echoed', 'in', 'the', 'ejecta', 'of', 'the', 'rsgs', 'wd120', 'and', '26', 'in', 'each', 'case', 'the', 'cometary', 'tails', 'are', 'directed', 'away', 'from', 'the', 'cluster', 'core', 'the', 'nebular', 'emission', 'around', 'the', 'rsg', 'wd1237', 'is', 'less', 'collimated', 'than', 'these', 'systems', 'but', 'once', 'again', 'appears', 'more', 'prominent', 'in', 'the', 'hemisphere', 'facing', 'the', 'cluster', 'considered', 'as', 'a', 'whole', 'the', 'nebular', 'morphologies', 'provide', 'compelling', 'evidence', 'for', 'sculpting', 'via', 'a', 'physical', 'agent', 'associated', 'with', 'westerlund', '1', 'such', 'as', 'a', 'cluster', 'wind']]
|
[-0.06272652857153165, 0.12245110472874113, -0.053930848802466104, 0.07796654824010084, -0.08501392392389162, -0.0928202673373088, 0.04952553273047465, 0.46098935491287374, -0.1314461953695339, -0.31509008554374457, 0.09667148866484099, -0.2957329956526068, -0.06660328113513303, 0.1719162394214769, -0.024322517781885683, -0.08833744050443015, 0.11623419220001817, -0.04271216830382169, 0.0032706315994826735, -0.2340932631468348, 0.278090549009839, 0.045455301933287326, 0.11527045793883817, -0.06413079571129728, 0.046803178088608344, -0.15843291896146158, -0.06409153993680916, -0.047309110596985886, -0.07275339549499184, 0.06495889054585091, 0.21785594082214463, 0.1462966719409451, 0.24987626312018543, -0.3563929867970062, -0.21287305137588525, 0.04293877149040116, 0.24415518436580896, 0.009992577043742361, -0.06264250676533369, -0.30905150443325347, 0.08221743532954912, -0.21679362995405746, -0.2477238550388687, 0.12814056825146494, 0.0838197864867537, 0.033414871484356026, -0.15930984152397337, 0.11216278943379941, -0.014543104476564315, 0.11356294129542271, -0.12932235794961716, -0.1596924188304168, -0.06237317680817386, 0.09597296520582282, -0.02028938055261445, 0.06318441511485988, 0.1373297179730209, -0.1406784566138989, -0.05341902308979295, 0.42523443320287313, -0.012768526560430985, 0.04077626058217351, 0.260635905990928, -0.22648998030172793, -0.237412914623913, 0.1754496608808322, 0.09812842476473545, 0.14643224152493697, -0.18471299363242816, -0.04694666470930597, -0.03667192314390723, 0.18546059553865607, 0.053536027635473916, 0.06908735415806443, 0.3230128001592214, 0.14425704599699188, 0.02772594142941312, 0.16151198846104384, -0.2752876538089739, -0.050320870115120014, -0.24348155482554099, -0.1118822604299746, -0.10089135277216178, 0.07428680761376212, -0.1526958344920914, -0.12809159594505384, 0.3379832521920473, 0.042085574355925776, 0.17715570931388458, -0.012692064816676552, 0.27146040019907164, 0.05124837224712779, 0.1287991899487064, 0.14805041559853813, 0.28756666037542616, 0.16807160206617866, 0.12674707489114412, -0.1896356566133581, 0.08569113043805873, -0.03789923506506889]
|
1,803.07009
|
Multi-access Edge Computing: The driver behind the wheel of 5G-connected
cars
|
The automotive and telco industries have taken an investment bet on the
connected car market, pushing for the digital transformation of the sector by
exploiting recent Information and Communication Technology (ICT) progress. As
ICT developments continue, it is expected that the technology advancements will
be able to fulfill the sophisticated requirements for vehicular use cases, such
as low latency and reliable communications for safety, high computing power to
process large amount of sensed data, and increased bandwidth for on-board
infotainment.
The aforementioned requirements have received significant focus during the
ongoing definition of the 3GPP 5G mobile standards, where there has been a
drive to facilitate vertical industries such as automotive, in addition to
providing the core aspects of the communication infrastructure. Of the
technology enablers for 5G, Multi-access Edge Computing (MEC) can be considered
essential. That is, a cloud environment located at the edge of the network, in
proximity of the end-users and coupled with the service provider's network
infrastructure. Even before 5G is rolled out, current mobile networks can
already target support for these challenging use cases using MEC technology.
This is because MEC is able to fulfill low latency and high bandwidth
requirements, and, in addition, it lends itself to be deployed at the vertical
industrial sector premises such as road infrastructure, air/sea ports, smart
factories, etc., thus, bringing computing power where it is needed most.
This work showcases the automotive use cases that are relevant for MEC,
providing insights into the technologies specified and investigated by the ETSI
MEC Industry Specification Group (ISG), who were the pioneer in creating a
standardized computing platform for advanced mobile networks with regards to
network edge related use cases.
|
cs.NI
|
the automotive and telco industries have taken an investment bet on the connected car market pushing for the digital transformation of the sector by exploiting recent information and communication technology ict progress as ict developments continue it is expected that the technology advancements will be able to fulfill the sophisticated requirements for vehicular use cases such as low latency and reliable communications for safety high computing power to process large amount of sensed data and increased bandwidth for onboard infotainment the aforementioned requirements have received significant focus during the ongoing definition of the 3gpp 5g mobile standards where there has been a drive to facilitate vertical industries such as automotive in addition to providing the core aspects of the communication infrastructure of the technology enablers for 5g multiaccess edge computing mec can be considered essential that is a cloud environment located at the edge of the network in proximity of the endusers and coupled with the service providers network infrastructure even before 5g is rolled out current mobile networks can already target support for these challenging use cases using mec technology this is because mec is able to fulfill low latency and high bandwidth requirements and in addition it lends itself to be deployed at the vertical industrial sector premises such as road infrastructure airsea ports smart factories etc thus bringing computing power where it is needed most this work showcases the automotive use cases that are relevant for mec providing insights into the technologies specified and investigated by the etsi mec industry specification group isg who were the pioneer in creating a standardized computing platform for advanced mobile networks with regards to network edge related use cases
|
[['the', 'automotive', 'and', 'telco', 'industries', 'have', 'taken', 'an', 'investment', 'bet', 'on', 'the', 'connected', 'car', 'market', 'pushing', 'for', 'the', 'digital', 'transformation', 'of', 'the', 'sector', 'by', 'exploiting', 'recent', 'information', 'and', 'communication', 'technology', 'ict', 'progress', 'as', 'ict', 'developments', 'continue', 'it', 'is', 'expected', 'that', 'the', 'technology', 'advancements', 'will', 'be', 'able', 'to', 'fulfill', 'the', 'sophisticated', 'requirements', 'for', 'vehicular', 'use', 'cases', 'such', 'as', 'low', 'latency', 'and', 'reliable', 'communications', 'for', 'safety', 'high', 'computing', 'power', 'to', 'process', 'large', 'amount', 'of', 'sensed', 'data', 'and', 'increased', 'bandwidth', 'for', 'onboard', 'infotainment', 'the', 'aforementioned', 'requirements', 'have', 'received', 'significant', 'focus', 'during', 'the', 'ongoing', 'definition', 'of', 'the', '3gpp', '5g', 'mobile', 'standards', 'where', 'there', 'has', 'been', 'a', 'drive', 'to', 'facilitate', 'vertical', 'industries', 'such', 'as', 'automotive', 'in', 'addition', 'to', 'providing', 'the', 'core', 'aspects', 'of', 'the', 'communication', 'infrastructure', 'of', 'the', 'technology', 'enablers', 'for', '5g', 'multiaccess', 'edge', 'computing', 'mec', 'can', 'be', 'considered', 'essential', 'that', 'is', 'a', 'cloud', 'environment', 'located', 'at', 'the', 'edge', 'of', 'the', 'network', 'in', 'proximity', 'of', 'the', 'endusers', 'and', 'coupled', 'with', 'the', 'service', 'providers', 'network', 'infrastructure', 'even', 'before', '5g', 'is', 'rolled', 'out', 'current', 'mobile', 'networks', 'can', 'already', 'target', 'support', 'for', 'these', 'challenging', 'use', 'cases', 'using', 'mec', 'technology', 'this', 'is', 'because', 'mec', 'is', 'able', 'to', 'fulfill', 'low', 'latency', 'and', 'high', 'bandwidth', 'requirements', 'and', 'in', 'addition', 'it', 'lends', 'itself', 'to', 'be', 'deployed', 'at', 'the', 'vertical', 'industrial', 'sector', 'premises', 'such', 'as', 'road', 'infrastructure', 'airsea', 'ports', 'smart', 'factories', 'etc', 'thus', 'bringing', 'computing', 'power', 'where', 'it', 'is', 'needed', 'most', 'this', 'work', 'showcases', 'the', 'automotive', 'use', 'cases', 'that', 'are', 'relevant', 'for', 'mec', 'providing', 'insights', 'into', 'the', 'technologies', 'specified', 'and', 'investigated', 'by', 'the', 'etsi', 'mec', 'industry', 'specification', 'group', 'isg', 'who', 'were', 'the', 'pioneer', 'in', 'creating', 'a', 'standardized', 'computing', 'platform', 'for', 'advanced', 'mobile', 'networks', 'with', 'regards', 'to', 'network', 'edge', 'related', 'use', 'cases']]
|
[-0.16726102208276447, 0.056888119339837825, 0.023917847684845863, 0.019577455104540637, -0.08931992585743985, -0.20066834740481412, 0.07555127124931904, 0.3803213302610549, -0.2381460712843645, -0.31768120812225364, 0.15877166585058725, -0.27541677170875317, -0.14969888422973185, 0.21197067647033352, -0.12997345207175307, 0.09331469434998568, 0.0660618288329846, 0.0009518318521461899, 0.03746206137869279, -0.25044171958692746, 0.24607019831942353, 0.09785402507735617, 0.38938778560112813, 0.13002113631981754, 0.007621036430405413, -0.02315295228010995, -0.035467713431408296, -0.04957381684713425, -0.05558975606194338, 0.16296009783693355, 0.3831760108968404, 0.20068447175632015, 0.3305846349903208, -0.5185689384238326, -0.21669753274516865, 0.08642261583479909, 0.1439370459076285, -0.011824110901425424, -0.04955810064109873, -0.3010833077308581, 0.10725187540814947, -0.2933121164213772, -0.14791578729134455, -0.05572983882177023, 0.034596871356429575, 0.04219526414786258, -0.25751298101176673, -0.06887849585380393, -0.03720094093160114, 0.05352557040776106, 0.005877957015177704, -0.08527911060637118, -0.023775891623654063, 0.2434587349575817, 0.018941080075309265, 0.04162822842803991, 0.1840293301435241, -0.1976667580853481, -0.10167010804879473, 0.41009456827640267, 0.04230552265276503, -0.1239426006527832, 0.16960638133631417, -0.03979941204118227, -0.16505807825856633, 0.05358091672202371, 0.22565845603989304, -0.03610592175998705, -0.2073847051640167, 0.07493488909865113, 0.056744389534968104, 0.10252518456164586, 0.06291627716574577, 0.0943237770995353, 0.2462077494015542, 0.25480604482514835, 0.14631756827555153, 0.09224978130412952, -0.06116865672717179, -0.11769008516604516, -0.2011246830886632, -0.16129748088646037, -0.17729366415644252, 0.005735399464493711, -0.03358945383090633, -0.08656936398750881, 0.3340208452302132, 0.18158182753049, 0.07990691463191651, 0.023262330532750692, 0.42659973191003575, 0.08735718646525613, 0.1686963742170081, 0.13451150551156923, 0.20537456151796765, 0.02281604978681388, 0.26465817199510744, -0.13084174622865327, 0.09731306637842091, -0.04465282725114978]
|
1,803.0701
|
Diffusion and first-passage characteristics on a dynamically evolving
support
|
We propose a generalized diffusion equation for a flat Euclidean space
subjected to a continuous infinitesimal scale transform. For the special cases
of an algebraic or exponential expansion/contraction, governed by
time-dependent scale factors $a(t)\sim t^\lambda$ and $a(t)\sim \exp(\mu t)$,
the partial differential equation is solved analytically and the asymptotic
scaling behavior, as well as the dynamical exponents, are derived. Whereas in
the algebraic case the two processes (diffusion and expansion) compete and a
crossover is observed, we find that for exponential dynamics the expansion
dominates on all time scales. For the case of contracting spaces, an algebraic
evolution slows down the overall dynamics, reflected in terms of a new
effective diffusion constant, whereas an exponential contraction neutralizes
the diffusive behavior entirely and leads to a stationary state. Furthermore,
we derive various first-passage properties and describe four qualitatively
different regimes of (strong) recurrent/transient behavior depending on the
scale factor exponent.
|
cond-mat.stat-mech
|
we propose a generalized diffusion equation for a flat euclidean space subjected to a continuous infinitesimal scale transform for the special cases of an algebraic or exponential expansioncontraction governed by timedependent scale factors atsim tlambda and atsim expmu t the partial differential equation is solved analytically and the asymptotic scaling behavior as well as the dynamical exponents are derived whereas in the algebraic case the two processes diffusion and expansion compete and a crossover is observed we find that for exponential dynamics the expansion dominates on all time scales for the case of contracting spaces an algebraic evolution slows down the overall dynamics reflected in terms of a new effective diffusion constant whereas an exponential contraction neutralizes the diffusive behavior entirely and leads to a stationary state furthermore we derive various firstpassage properties and describe four qualitatively different regimes of strong recurrenttransient behavior depending on the scale factor exponent
|
[['we', 'propose', 'a', 'generalized', 'diffusion', 'equation', 'for', 'a', 'flat', 'euclidean', 'space', 'subjected', 'to', 'a', 'continuous', 'infinitesimal', 'scale', 'transform', 'for', 'the', 'special', 'cases', 'of', 'an', 'algebraic', 'or', 'exponential', 'expansioncontraction', 'governed', 'by', 'timedependent', 'scale', 'factors', 'atsim', 'tlambda', 'and', 'atsim', 'expmu', 't', 'the', 'partial', 'differential', 'equation', 'is', 'solved', 'analytically', 'and', 'the', 'asymptotic', 'scaling', 'behavior', 'as', 'well', 'as', 'the', 'dynamical', 'exponents', 'are', 'derived', 'whereas', 'in', 'the', 'algebraic', 'case', 'the', 'two', 'processes', 'diffusion', 'and', 'expansion', 'compete', 'and', 'a', 'crossover', 'is', 'observed', 'we', 'find', 'that', 'for', 'exponential', 'dynamics', 'the', 'expansion', 'dominates', 'on', 'all', 'time', 'scales', 'for', 'the', 'case', 'of', 'contracting', 'spaces', 'an', 'algebraic', 'evolution', 'slows', 'down', 'the', 'overall', 'dynamics', 'reflected', 'in', 'terms', 'of', 'a', 'new', 'effective', 'diffusion', 'constant', 'whereas', 'an', 'exponential', 'contraction', 'neutralizes', 'the', 'diffusive', 'behavior', 'entirely', 'and', 'leads', 'to', 'a', 'stationary', 'state', 'furthermore', 'we', 'derive', 'various', 'firstpassage', 'properties', 'and', 'describe', 'four', 'qualitatively', 'different', 'regimes', 'of', 'strong', 'recurrenttransient', 'behavior', 'depending', 'on', 'the', 'scale', 'factor', 'exponent']]
|
[-0.1516066241185055, 0.1713085347479579, -0.10315434813084132, 0.10735906605495492, -0.05610922115699174, -0.13097705736337859, 0.002352055493345786, 0.2958618008029786, -0.33026031842864295, -0.21729195196530782, 0.11079130836013654, -0.2558239305909484, -0.143647563717693, 0.1816057867144008, 0.03426567548760087, 0.04210509842960164, -0.03718264214537182, 0.03222306930095058, -0.08283322045069842, -0.1976576335146092, 0.33466425204548883, 0.018386816487347114, 0.27670385371704864, 0.016606233498031222, 0.14749518622065316, -0.016580418230512657, -0.0028648127768679545, 0.04039576688590977, -0.1848317604983242, 0.009484444383053563, 0.18006921625252487, 0.012847171580368603, 0.225180132849444, -0.40821718394038947, -0.21598651131539923, 0.0828415947821545, 0.21082744011466667, 0.07298646451326439, -0.005593760425187144, -0.24345165940718977, 0.01098814037804668, -0.1369816017324558, -0.18888269344697128, -0.07426012656336801, 0.06606785398184296, 0.024283934419194388, -0.2866899610773937, 0.14622562686103313, 0.08099017093863457, 0.03778592219444092, -0.08103464245859131, -0.07569793772622566, 0.02703025083866197, 0.12002453333666749, 0.0603303339913583, -0.002976894658688154, 0.12875801746456608, -0.11935373249061003, -0.08627965352757569, 0.36346987363051725, -0.12659268174477778, -0.20763795704555674, 0.1724864006779122, -0.15502817147549847, -0.10295024711475079, 0.1422470809201194, 0.1553220100436561, 0.13729988864597054, -0.1280746384621346, 0.1472964036047169, 0.018346807734790648, 0.12895751948392875, 0.07179047662695567, 0.00888589909614844, 0.08377935432567815, 0.1377837806373734, 0.05801489931213468, 0.13926095853565965, -0.025326200125336245, -0.1859853116750585, -0.30755461928610867, -0.12703040171402027, -0.12718045059512872, 0.12225932694933805, -0.17966994861450764, -0.19479929831042583, 0.37479231176532907, 0.06301391358499893, 0.23203763359924778, 0.11667664166432931, 0.21393177867867053, 0.18823905317333048, -0.010116448039126053, 0.09459899911603684, 0.1908736416151294, 0.11488201499859979, 0.10428779073550391, -0.2721122878672857, 0.09601443296776631, 0.10097291408345808]
|
1,803.07011
|
Radio bearing of sources with directional antennas in urban environment
|
This paper focuses on assessing the limitations in the direction-finding
process of radio sources with directional antennas in an urbanized environment,
demonstrating how signal source antenna parameters, such as beamwidth and
maximum radiation direction affect bearing accuracy in non-line-of-sight (NLOS)
conditions. These evaluations are based on simulation studies, which use
measurement-tested signal processing procedures. These procedures are based on
a multi-elliptical propagation model, the geometry of which is related to the
environment by the power delay profile or spectrum. The probability density
function of the angle of arrival for different parameters of the transmitting
antenna is the simulation result. This characteristic allows assessing the
effect of the signal source antenna parameters on bearing error. The obtained
results are the basis for practical correction bearing error and these show the
possibility of improving the efficiency of the radio source location in the
urbanized environment.
|
cs.IT math.IT
|
this paper focuses on assessing the limitations in the directionfinding process of radio sources with directional antennas in an urbanized environment demonstrating how signal source antenna parameters such as beamwidth and maximum radiation direction affect bearing accuracy in nonlineofsight nlos conditions these evaluations are based on simulation studies which use measurementtested signal processing procedures these procedures are based on a multielliptical propagation model the geometry of which is related to the environment by the power delay profile or spectrum the probability density function of the angle of arrival for different parameters of the transmitting antenna is the simulation result this characteristic allows assessing the effect of the signal source antenna parameters on bearing error the obtained results are the basis for practical correction bearing error and these show the possibility of improving the efficiency of the radio source location in the urbanized environment
|
[['this', 'paper', 'focuses', 'on', 'assessing', 'the', 'limitations', 'in', 'the', 'directionfinding', 'process', 'of', 'radio', 'sources', 'with', 'directional', 'antennas', 'in', 'an', 'urbanized', 'environment', 'demonstrating', 'how', 'signal', 'source', 'antenna', 'parameters', 'such', 'as', 'beamwidth', 'and', 'maximum', 'radiation', 'direction', 'affect', 'bearing', 'accuracy', 'in', 'nonlineofsight', 'nlos', 'conditions', 'these', 'evaluations', 'are', 'based', 'on', 'simulation', 'studies', 'which', 'use', 'measurementtested', 'signal', 'processing', 'procedures', 'these', 'procedures', 'are', 'based', 'on', 'a', 'multielliptical', 'propagation', 'model', 'the', 'geometry', 'of', 'which', 'is', 'related', 'to', 'the', 'environment', 'by', 'the', 'power', 'delay', 'profile', 'or', 'spectrum', 'the', 'probability', 'density', 'function', 'of', 'the', 'angle', 'of', 'arrival', 'for', 'different', 'parameters', 'of', 'the', 'transmitting', 'antenna', 'is', 'the', 'simulation', 'result', 'this', 'characteristic', 'allows', 'assessing', 'the', 'effect', 'of', 'the', 'signal', 'source', 'antenna', 'parameters', 'on', 'bearing', 'error', 'the', 'obtained', 'results', 'are', 'the', 'basis', 'for', 'practical', 'correction', 'bearing', 'error', 'and', 'these', 'show', 'the', 'possibility', 'of', 'improving', 'the', 'efficiency', 'of', 'the', 'radio', 'source', 'location', 'in', 'the', 'urbanized', 'environment']]
|
[-0.16900967502741948, 0.04211401537232884, -0.030113748704076657, 0.005783590302844008, -0.06936776862440115, -0.10749712867450946, 0.05144609754379997, 0.42827681685857316, -0.22191695017568397, -0.33019203051317036, 0.11441806092171382, -0.24924893470009185, -0.1412816781844574, 0.23469649060094294, -0.0627973683026507, 0.06814284958870065, 0.05700722181548675, 0.02139353884899236, -0.040841396524016055, -0.19364280459728647, 0.3016145757425378, 0.17191199377733976, 0.3488849578689493, 0.055051032450472846, 0.08862129042374221, 0.013410038783723582, -0.07043707301073991, -0.03249745592047668, -0.06726206476545847, 0.08328558275383627, 0.22923297359746822, 0.18531004138000257, 0.22634173190577866, -0.403359707801583, -0.26680447204791485, 0.07001854440342661, 0.10483456011250589, 0.0686747603191076, -0.06732654628667531, -0.3018349201867608, 0.053764943492512964, -0.1380385867607324, -0.11635518192597633, 0.07124735111806621, -0.04050498072500506, 0.10727338400728842, -0.27183908440423665, 0.07525145914405584, 0.007123705072341659, 0.05662661329810078, -0.03694799034492978, -0.14790407718152654, 0.03023043257045619, 0.17626584940656015, 0.053705887686327454, -0.013581501547881264, 0.18005619484085775, -0.1271413579213281, -0.09044307575508265, 0.36204655156702015, -0.029087902226729703, -0.24634300016448007, 0.14392307390465486, -0.14402027410873647, -0.11132953518750609, 0.1278897758469263, 0.2501114110746388, 0.0824939269863122, -0.14442953900417563, 0.017837406676890103, 0.036648330859119956, 0.18731272618240075, 0.06529140653392525, 0.08473863178560286, 0.2042734254653572, 0.16637186731165604, 0.08089986415117556, 0.13575347255360573, -0.17710006636970327, -0.04566689952877714, -0.27280446809736336, -0.11406891656286539, -0.19062338333497655, -0.001394500648800997, -0.12882629484710192, -0.1204058555981098, 0.4088417864305542, 0.19792679801636132, 0.13945695658128524, 0.051911487400941286, 0.38257670920368625, 0.12284842662592517, 0.017308576613770308, 0.0633088703571112, 0.2588803118610002, 0.10491797527965449, 0.07015981836944607, -0.23630174559190975, 0.1244391914793944, -0.027482369077451368]
|
1,803.07012
|
Conditional $\pi$-Phase Shift of Single-Photon-Level Pulses at Room
Temperature
|
The development of useful photon-photon interactions can trigger numerous
breakthroughs in quantum information science, however this has remained a
considerable challenge spanning several decades. Here we demonstrate the first
room-temperature implementation of large phase shifts ($\approx\pi$) on a
single-photon level probe pulse (1.5us) triggered by a
simultaneously-propagating few-photon-level signal field. This process is
mediated by $Rb^{87}$ vapor in a double-$\Lambda$ atomic configuration. We use
homodyne tomography to obtain the quadrature statistics of the phase-shifted
quantum fields and perform maximum-likelihood estimation to reconstruct their
quantum state in the Fock state basis. For the probe field, we have observed
input-output fidelities higher than 90$\%$ for phase-shifted output states, and
high overlap (over 90\%) with a theoretically perfect coherent state. Our
noise-free, four-wave-mixing-mediated photon-photon interface is a key
milestone towards developing quantum logic and nondemolition photon detection
using schemes such as coherent photon conversion.
|
quant-ph
|
the development of useful photonphoton interactions can trigger numerous breakthroughs in quantum information science however this has remained a considerable challenge spanning several decades here we demonstrate the first roomtemperature implementation of large phase shifts approxpi on a singlephoton level probe pulse 15us triggered by a simultaneouslypropagating fewphotonlevel signal field this process is mediated by rb87 vapor in a doublelambda atomic configuration we use homodyne tomography to obtain the quadrature statistics of the phaseshifted quantum fields and perform maximumlikelihood estimation to reconstruct their quantum state in the fock state basis for the probe field we have observed inputoutput fidelities higher than 90 for phaseshifted output states and high overlap over 90 with a theoretically perfect coherent state our noisefree fourwavemixingmediated photonphoton interface is a key milestone towards developing quantum logic and nondemolition photon detection using schemes such as coherent photon conversion
|
[['the', 'development', 'of', 'useful', 'photonphoton', 'interactions', 'can', 'trigger', 'numerous', 'breakthroughs', 'in', 'quantum', 'information', 'science', 'however', 'this', 'has', 'remained', 'a', 'considerable', 'challenge', 'spanning', 'several', 'decades', 'here', 'we', 'demonstrate', 'the', 'first', 'roomtemperature', 'implementation', 'of', 'large', 'phase', 'shifts', 'approxpi', 'on', 'a', 'singlephoton', 'level', 'probe', 'pulse', '15us', 'triggered', 'by', 'a', 'simultaneouslypropagating', 'fewphotonlevel', 'signal', 'field', 'this', 'process', 'is', 'mediated', 'by', 'rb87', 'vapor', 'in', 'a', 'doublelambda', 'atomic', 'configuration', 'we', 'use', 'homodyne', 'tomography', 'to', 'obtain', 'the', 'quadrature', 'statistics', 'of', 'the', 'phaseshifted', 'quantum', 'fields', 'and', 'perform', 'maximumlikelihood', 'estimation', 'to', 'reconstruct', 'their', 'quantum', 'state', 'in', 'the', 'fock', 'state', 'basis', 'for', 'the', 'probe', 'field', 'we', 'have', 'observed', 'inputoutput', 'fidelities', 'higher', 'than', '90', 'for', 'phaseshifted', 'output', 'states', 'and', 'high', 'overlap', 'over', '90', 'with', 'a', 'theoretically', 'perfect', 'coherent', 'state', 'our', 'noisefree', 'fourwavemixingmediated', 'photonphoton', 'interface', 'is', 'a', 'key', 'milestone', 'towards', 'developing', 'quantum', 'logic', 'and', 'nondemolition', 'photon', 'detection', 'using', 'schemes', 'such', 'as', 'coherent', 'photon', 'conversion']]
|
[-0.1240904723654372, 0.20201523469448307, -0.04794755221189877, 0.04124075735638602, -0.017153152468593887, -0.15675468777517115, 0.09002307885543981, 0.4217771789888396, -0.22262197471543277, -0.30104307437410754, 0.05692448284065718, -0.23631699081598678, -0.09254795184059844, 0.24247691401001745, -0.0061097431576575606, 0.12405184781464347, 0.07741644047540579, -0.017963014250743564, -0.03323999551009305, -0.1990036409880191, 0.23186630517733794, 0.0716753572133798, 0.3500354951689441, 0.031363517490392345, 0.17044512819104496, 0.036426960714977155, 0.01920639312261865, -0.08311037685854673, -0.08432328340386713, 0.0993867511737813, 0.31927885985797283, 0.11350897718628827, 0.2710187438481154, -0.43985389086016774, -0.2096165864758982, 0.10466977354329433, 0.14312707001630584, 0.21940920640626094, -0.08587583513118081, -0.33748858644674623, -0.012082708606719087, -0.190283659730025, -0.05751950252311726, -0.11686335671965005, -0.0026529719832142557, -0.04765094289926635, -0.2382327786504026, 0.04487374090983866, -0.006657543980914175, 0.07236589145350412, 0.03364520828939811, -0.03539448632539189, 0.035384461081444024, 0.08637086312578869, -0.12817539104339531, 0.06128069006750381, 0.16465882594309691, -0.17914349452191353, -0.20495735582671243, 0.32091414991657446, -0.0911693776840638, -0.12489953672302628, 0.1462315886492168, -0.15813560137205696, -0.0811787857776032, 0.16718863771997228, 0.14677994635914635, 0.0979059472370784, -0.12108935710776897, 0.031081463531913902, 0.02497065507120242, 0.22173730413137127, 0.09308112214190246, 0.1581853702273492, 0.21874161355238217, 0.18328788061456305, 0.054667503792235124, 0.1653643638731735, -0.13493278240219922, -0.10508086819143925, -0.26161624292034086, -0.1658031914882824, -0.20245241453313698, 0.08374502328156501, -0.017500833050457482, -0.11861495528859596, 0.4068831771979258, 0.16362076996227415, 0.14747016455971357, -0.04747168029774062, 0.3675467718569358, 0.14044131142474767, 0.00925560371889087, 0.009594237771782562, 0.3262998717429157, 0.19815228921259298, 0.0821492967984374, -0.2045372164413931, 0.05864687256147935, -0.030576243578544715]
|
1,803.07013
|
Leading Logarithms of the Two Point Function in Massless O(N) and SU(N)
Models to any Order from Analyticity and Unitarity
|
Leading (large) logarithms in non-renormalizable theories have been
investigated in the recent past. Besides some general considerations, explicit
results for the expansion coefficients (in terms of leading logarithms) of
partial wave amplitudes and of scalar and vector form factors have been given.
Analyticity and unitarity constraints haven been used to obtain the expansion
coefficients of partial waves in massless theories, yielding form factors and
the scalar two-point function to five-loop order in the O(4)/O(3) model. Later,
the all order solutions for the partial waves in any O(N+1)/O(N) model were
found. Also, results up to four-loop order exist for massive theories. Here we
extend the implications of analyticity and unitarity constraints on the leading
logarithms to arbitrary loop order in massless theories. We explicitly obtain
the scalar and vector form factors as well as to the scalar two-point function
in any O(N) and SU(N) type models. We present relations between the expansion
coefficients of these quantities and those of of the relevant partial waves.
Our work offers a consistency check on the published results in the O(N) models
for form factors, and new results for the scalar two-point function. For the
SU(N) type models, we use the known expansion coefficients for partial waves to
obtain those for scalar and vector form factors as well as for the scalar
two-point function. Our results for the form factor offer a check for the known
and future results for massive O(N) and SU(N) type models when the massless
limit is taken. Mathematica notebooks which can be used to calculate the
expansion coefficients are provided as ancillary files.
|
hep-ph
|
leading large logarithms in nonrenormalizable theories have been investigated in the recent past besides some general considerations explicit results for the expansion coefficients in terms of leading logarithms of partial wave amplitudes and of scalar and vector form factors have been given analyticity and unitarity constraints haven been used to obtain the expansion coefficients of partial waves in massless theories yielding form factors and the scalar twopoint function to fiveloop order in the o4o3 model later the all order solutions for the partial waves in any on1on model were found also results up to fourloop order exist for massive theories here we extend the implications of analyticity and unitarity constraints on the leading logarithms to arbitrary loop order in massless theories we explicitly obtain the scalar and vector form factors as well as to the scalar twopoint function in any on and sun type models we present relations between the expansion coefficients of these quantities and those of of the relevant partial waves our work offers a consistency check on the published results in the on models for form factors and new results for the scalar twopoint function for the sun type models we use the known expansion coefficients for partial waves to obtain those for scalar and vector form factors as well as for the scalar twopoint function our results for the form factor offer a check for the known and future results for massive on and sun type models when the massless limit is taken mathematica notebooks which can be used to calculate the expansion coefficients are provided as ancillary files
|
[['leading', 'large', 'logarithms', 'in', 'nonrenormalizable', 'theories', 'have', 'been', 'investigated', 'in', 'the', 'recent', 'past', 'besides', 'some', 'general', 'considerations', 'explicit', 'results', 'for', 'the', 'expansion', 'coefficients', 'in', 'terms', 'of', 'leading', 'logarithms', 'of', 'partial', 'wave', 'amplitudes', 'and', 'of', 'scalar', 'and', 'vector', 'form', 'factors', 'have', 'been', 'given', 'analyticity', 'and', 'unitarity', 'constraints', 'haven', 'been', 'used', 'to', 'obtain', 'the', 'expansion', 'coefficients', 'of', 'partial', 'waves', 'in', 'massless', 'theories', 'yielding', 'form', 'factors', 'and', 'the', 'scalar', 'twopoint', 'function', 'to', 'fiveloop', 'order', 'in', 'the', 'o4o3', 'model', 'later', 'the', 'all', 'order', 'solutions', 'for', 'the', 'partial', 'waves', 'in', 'any', 'on1on', 'model', 'were', 'found', 'also', 'results', 'up', 'to', 'fourloop', 'order', 'exist', 'for', 'massive', 'theories', 'here', 'we', 'extend', 'the', 'implications', 'of', 'analyticity', 'and', 'unitarity', 'constraints', 'on', 'the', 'leading', 'logarithms', 'to', 'arbitrary', 'loop', 'order', 'in', 'massless', 'theories', 'we', 'explicitly', 'obtain', 'the', 'scalar', 'and', 'vector', 'form', 'factors', 'as', 'well', 'as', 'to', 'the', 'scalar', 'twopoint', 'function', 'in', 'any', 'on', 'and', 'sun', 'type', 'models', 'we', 'present', 'relations', 'between', 'the', 'expansion', 'coefficients', 'of', 'these', 'quantities', 'and', 'those', 'of', 'of', 'the', 'relevant', 'partial', 'waves', 'our', 'work', 'offers', 'a', 'consistency', 'check', 'on', 'the', 'published', 'results', 'in', 'the', 'on', 'models', 'for', 'form', 'factors', 'and', 'new', 'results', 'for', 'the', 'scalar', 'twopoint', 'function', 'for', 'the', 'sun', 'type', 'models', 'we', 'use', 'the', 'known', 'expansion', 'coefficients', 'for', 'partial', 'waves', 'to', 'obtain', 'those', 'for', 'scalar', 'and', 'vector', 'form', 'factors', 'as', 'well', 'as', 'for', 'the', 'scalar', 'twopoint', 'function', 'our', 'results', 'for', 'the', 'form', 'factor', 'offer', 'a', 'check', 'for', 'the', 'known', 'and', 'future', 'results', 'for', 'massive', 'on', 'and', 'sun', 'type', 'models', 'when', 'the', 'massless', 'limit', 'is', 'taken', 'mathematica', 'notebooks', 'which', 'can', 'be', 'used', 'to', 'calculate', 'the', 'expansion', 'coefficients', 'are', 'provided', 'as', 'ancillary', 'files']]
|
[-0.11245411965029158, 0.10057619244272586, -0.06024602301482543, 0.10732658793803176, -0.09989879051052773, -0.06865584064907757, -0.005818502109263177, 0.29931937941556214, -0.17884957420867192, -0.2770108772345769, 0.1150999857012346, -0.2964010558798483, -0.16065737858453752, 0.1918692211638283, 0.06635331894263967, 0.10705457497672498, 0.005064280803194483, 0.07049258430041852, -0.0872758281246567, -0.2775524696370743, 0.34262976227932473, 0.019096153105772635, 0.21272446674771095, 0.08844393793536165, 0.07834903224911682, 0.0034567451238710404, -0.05622631855280572, -0.012433847755492302, -0.14640194814968124, 0.09127759866244053, 0.2153117346410388, 0.10230702039419552, 0.17430928487771455, -0.4338127463862286, -0.22156724970048394, 0.05216287376220473, 0.1667003408900839, 0.12591612768379032, 0.0002111009831312788, -0.26384703728604975, 0.08053537477620963, -0.18923785520063444, -0.17033561512486625, -0.1496290369563601, 0.004126003651901056, -0.0037269416595773616, -0.33794840911531265, 0.10442893962873029, -0.004694756441251979, -0.0011773584330568218, -0.07084802522338245, -0.15326695436681087, 0.01650069226628127, 0.1412666941179142, 0.11252483774068986, 0.03536112798832869, 0.052703854752320596, -0.20426777484720104, -0.12562980068263682, 0.3877156186139723, -0.11179546736187891, -0.23711687746059634, 0.1550666056573391, -0.17204621655045377, -0.15584651502346947, 0.06431452696432026, 0.1987819384120561, 0.1240867455140021, -0.13962246200989778, 0.12959648939364996, -0.012201106593398047, 0.11783449819759388, 0.11107701356593833, 0.06423735445767875, 0.18388775479668779, 0.025503366594629377, -0.017705663484130198, 0.11519721382651264, 0.003577944363168803, -0.08016360320154407, -0.36437738113787793, -0.15715751715647838, -0.08548962305706947, 0.03367031920710818, -0.13589721782795483, -0.16050820012278286, 0.37137899955357817, 0.1218661448193131, 0.19328997152118113, 0.07671101289518703, 0.25963423325047463, 0.1851970908798114, 0.11561251791746832, 0.06700716264375293, 0.2520315291930767, 0.16384556011264817, 0.08362321937918833, -0.17297289569889734, 0.014888747409074959, 0.12182624894905238]
|
1,803.07014
|
Two-photon interference in the telecom C-band after frequency conversion
of photons from remote quantum emitters
|
Efficient fiber-based long-distance quantum communication via quantum
repeaters relies on deterministic single-photon sources at telecom wavelengths,
with the potential to exploit the existing world-wide infrastructures. For
upscaling the experimental complexity in quantum networking, two-photon
interference (TPI) of remote non-classical emitters in the low-loss telecom
bands is of utmost importance. With respect to TPI of distinct emitters,
several experiments have been conducted, e.g., using trapped atoms
[Beugnon2006], ions [Maunz2007], NV-centers [Bernien2012, Sipahigil2012],
SiV-centers [Sipahigil2014], organic molecules [Lettow2010] and semiconductor
quantum dots (QDs) [Patel2010, Flagg2010, He2013b, Gold2014, Giesz2015,
Thoma2017, Reindl2017, Zopf2017]; however, the spectral range was far from the
highly desirable telecom C-band. Here, we report on TPI at 1550 nm between
down-converted single photons from remote QDs [Michler2017Book], demonstrating
quantum frequency conversion [Zaske2012, Ates2012, Kambs2016] as precise and
stable mechanism to erase the frequency difference between independent
emitters. On resonance, a TPI-visibility of (29+-3)% has been observed, being
only limited by spectral diffusion processes of the individual QDs
[Robinson2000, Kuhlmann2015]. Up to 2-km of additional fiber channel has been
introduced in both or individual signal paths with no influence on
TPI-visibility, proving negligible photon wave-packet distortion. The present
experiment is conducted within a local fiber network covering several rooms
between two floors of the building. Our studies pave the way to establish
long-distance entanglement distribution between remote solid-state emitters
including interfaces with various quantum hybrid systems
[DeGreve2012,Maring2017,Bock2017,Maring2018].
|
quant-ph cond-mat.mes-hall physics.app-ph physics.optics
|
efficient fiberbased longdistance quantum communication via quantum repeaters relies on deterministic singlephoton sources at telecom wavelengths with the potential to exploit the existing worldwide infrastructures for upscaling the experimental complexity in quantum networking twophoton interference tpi of remote nonclassical emitters in the lowloss telecom bands is of utmost importance with respect to tpi of distinct emitters several experiments have been conducted eg using trapped atoms beugnon2006 ions maunz2007 nvcenters bernien2012 sipahigil2012 sivcenters sipahigil2014 organic molecules lettow2010 and semiconductor quantum dots qds patel2010 flagg2010 he2013b gold2014 giesz2015 thoma2017 reindl2017 zopf2017 however the spectral range was far from the highly desirable telecom cband here we report on tpi at 1550 nm between downconverted single photons from remote qds michler2017book demonstrating quantum frequency conversion zaske2012 ates2012 kambs2016 as precise and stable mechanism to erase the frequency difference between independent emitters on resonance a tpivisibility of 293 has been observed being only limited by spectral diffusion processes of the individual qds robinson2000 kuhlmann2015 up to 2km of additional fiber channel has been introduced in both or individual signal paths with no influence on tpivisibility proving negligible photon wavepacket distortion the present experiment is conducted within a local fiber network covering several rooms between two floors of the building our studies pave the way to establish longdistance entanglement distribution between remote solidstate emitters including interfaces with various quantum hybrid systems degreve2012maring2017bock2017maring2018
|
[['efficient', 'fiberbased', 'longdistance', 'quantum', 'communication', 'via', 'quantum', 'repeaters', 'relies', 'on', 'deterministic', 'singlephoton', 'sources', 'at', 'telecom', 'wavelengths', 'with', 'the', 'potential', 'to', 'exploit', 'the', 'existing', 'worldwide', 'infrastructures', 'for', 'upscaling', 'the', 'experimental', 'complexity', 'in', 'quantum', 'networking', 'twophoton', 'interference', 'tpi', 'of', 'remote', 'nonclassical', 'emitters', 'in', 'the', 'lowloss', 'telecom', 'bands', 'is', 'of', 'utmost', 'importance', 'with', 'respect', 'to', 'tpi', 'of', 'distinct', 'emitters', 'several', 'experiments', 'have', 'been', 'conducted', 'eg', 'using', 'trapped', 'atoms', 'beugnon2006', 'ions', 'maunz2007', 'nvcenters', 'bernien2012', 'sipahigil2012', 'sivcenters', 'sipahigil2014', 'organic', 'molecules', 'lettow2010', 'and', 'semiconductor', 'quantum', 'dots', 'qds', 'patel2010', 'flagg2010', 'he2013b', 'gold2014', 'giesz2015', 'thoma2017', 'reindl2017', 'zopf2017', 'however', 'the', 'spectral', 'range', 'was', 'far', 'from', 'the', 'highly', 'desirable', 'telecom', 'cband', 'here', 'we', 'report', 'on', 'tpi', 'at', '1550', 'nm', 'between', 'downconverted', 'single', 'photons', 'from', 'remote', 'qds', 'michler2017book', 'demonstrating', 'quantum', 'frequency', 'conversion', 'zaske2012', 'ates2012', 'kambs2016', 'as', 'precise', 'and', 'stable', 'mechanism', 'to', 'erase', 'the', 'frequency', 'difference', 'between', 'independent', 'emitters', 'on', 'resonance', 'a', 'tpivisibility', 'of', '293', 'has', 'been', 'observed', 'being', 'only', 'limited', 'by', 'spectral', 'diffusion', 'processes', 'of', 'the', 'individual', 'qds', 'robinson2000', 'kuhlmann2015', 'up', 'to', '2km', 'of', 'additional', 'fiber', 'channel', 'has', 'been', 'introduced', 'in', 'both', 'or', 'individual', 'signal', 'paths', 'with', 'no', 'influence', 'on', 'tpivisibility', 'proving', 'negligible', 'photon', 'wavepacket', 'distortion', 'the', 'present', 'experiment', 'is', 'conducted', 'within', 'a', 'local', 'fiber', 'network', 'covering', 'several', 'rooms', 'between', 'two', 'floors', 'of', 'the', 'building', 'our', 'studies', 'pave', 'the', 'way', 'to', 'establish', 'longdistance', 'entanglement', 'distribution', 'between', 'remote', 'solidstate', 'emitters', 'including', 'interfaces', 'with', 'various', 'quantum', 'hybrid', 'systems', 'degreve2012maring2017bock2017maring2018']]
|
[-0.14729073239458115, 0.1730362368306136, -0.023080824330301567, -0.01793534136397446, 0.018073229488022258, -0.23403994821583723, 0.09728053962871765, 0.49960903187125627, -0.21096117058907185, -0.3065535122759774, 0.025518579918563846, -0.3215576802002321, -0.058814361346263146, 0.270284248288896, 0.0019686775331588294, 0.12272913799630386, 0.04350615906676665, -0.07025269890033484, 0.024401456604038578, -0.14167635934023962, 0.24129676691428348, 0.07128423286168513, 0.36230485073733376, 0.09064185187349667, 0.10985548382320691, -0.009051600224476788, 0.010316052886433807, -0.12197348592505504, -0.06990055411784347, 0.1424533452626576, 0.30742617271189915, 0.03619932552068673, 0.26571981113699106, -0.43916689036275713, -0.23495255015089667, 0.10424095411130255, 0.15885585278125958, 0.12329005589823949, -0.0761837569102276, -0.332545538949273, 0.04105451197500599, -0.13229682930920383, -0.0436660438841716, -0.0012119766376626742, -0.01699596141133052, 0.02160297612150172, -0.1950203790306344, 0.02700470446258562, -0.029625412646109368, 0.09622159797587607, 0.06005982566385133, -0.059842448407267726, 0.018843155881011913, 0.14038851505979932, -0.08670780127568373, -0.03566363933588387, 0.19623876774526838, -0.08706622454683564, -0.18770086246261392, 0.3606175579554816, -0.046838041669274175, -0.07348968591056948, 0.1918406468538895, -0.15000738665498425, -0.06314846252017461, 0.14461127467831542, 0.15633749251114434, 0.0942007500671385, -0.14640322711438605, 0.044052857061327055, 0.04982599511392193, 0.23448201620059161, 0.1208614496730895, 0.2337697036258904, 0.22285825850229968, 0.1654314173911099, 0.039802430677089363, 0.15038137627986842, -0.12262677903388544, -0.1184338175917579, -0.24135610996687895, -0.1662714946369576, -0.2345406468588822, 0.08769310492962266, -0.07627915093974362, -0.11624826185519364, 0.35746245803933885, 0.13086397467079655, 0.11569225405905359, -0.02246774431539349, 0.3316638262396088, 0.07076986436040537, 0.10090196937193523, 0.021811024545878344, 0.30937412809027304, 0.15713718385691525, 0.09438292407615129, -0.22196933566500424, 0.03210807626197889, -0.07878831715442904]
|
1,803.07015
|
Live Target Detection with Deep Learning Neural Network and Unmanned
Aerial Vehicle on Android Mobile Device
|
This paper describes the stages faced during the development of an Android
program which obtains and decodes live images from DJI Phantom 3 Professional
Drone and implements certain features of the TensorFlow Android Camera Demo
application. Test runs were made and outputs of the application were noted. A
lake was classified as seashore, breakwater and pier with the proximities of
24.44%, 21.16% and 12.96% respectfully. The joystick of the UAV controller and
laptop keyboard was classified with the proximities of 19.10% and 13.96%
respectfully. The laptop monitor was classified as screen, monitor and
television with the proximities of 18.77%, 14.76% and 14.00% respectfully. The
computer used during the development of this study was classified as notebook
and laptop with the proximities of 20.04% and 11.68% respectfully. A tractor
parked at a parking lot was classified with the proximity of 12.88%. A group of
cars in the same parking lot were classified as sports car, racer and
convertible with the proximities of 31.75%, 18.64% and 13.45% respectfully at
an inference time of 851ms.
|
cs.CV
|
this paper describes the stages faced during the development of an android program which obtains and decodes live images from dji phantom 3 professional drone and implements certain features of the tensorflow android camera demo application test runs were made and outputs of the application were noted a lake was classified as seashore breakwater and pier with the proximities of 2444 2116 and 1296 respectfully the joystick of the uav controller and laptop keyboard was classified with the proximities of 1910 and 1396 respectfully the laptop monitor was classified as screen monitor and television with the proximities of 1877 1476 and 1400 respectfully the computer used during the development of this study was classified as notebook and laptop with the proximities of 2004 and 1168 respectfully a tractor parked at a parking lot was classified with the proximity of 1288 a group of cars in the same parking lot were classified as sports car racer and convertible with the proximities of 3175 1864 and 1345 respectfully at an inference time of 851ms
|
[['this', 'paper', 'describes', 'the', 'stages', 'faced', 'during', 'the', 'development', 'of', 'an', 'android', 'program', 'which', 'obtains', 'and', 'decodes', 'live', 'images', 'from', 'dji', 'phantom', '3', 'professional', 'drone', 'and', 'implements', 'certain', 'features', 'of', 'the', 'tensorflow', 'android', 'camera', 'demo', 'application', 'test', 'runs', 'were', 'made', 'and', 'outputs', 'of', 'the', 'application', 'were', 'noted', 'a', 'lake', 'was', 'classified', 'as', 'seashore', 'breakwater', 'and', 'pier', 'with', 'the', 'proximities', 'of', '2444', '2116', 'and', '1296', 'respectfully', 'the', 'joystick', 'of', 'the', 'uav', 'controller', 'and', 'laptop', 'keyboard', 'was', 'classified', 'with', 'the', 'proximities', 'of', '1910', 'and', '1396', 'respectfully', 'the', 'laptop', 'monitor', 'was', 'classified', 'as', 'screen', 'monitor', 'and', 'television', 'with', 'the', 'proximities', 'of', '1877', '1476', 'and', '1400', 'respectfully', 'the', 'computer', 'used', 'during', 'the', 'development', 'of', 'this', 'study', 'was', 'classified', 'as', 'notebook', 'and', 'laptop', 'with', 'the', 'proximities', 'of', '2004', 'and', '1168', 'respectfully', 'a', 'tractor', 'parked', 'at', 'a', 'parking', 'lot', 'was', 'classified', 'with', 'the', 'proximity', 'of', '1288', 'a', 'group', 'of', 'cars', 'in', 'the', 'same', 'parking', 'lot', 'were', 'classified', 'as', 'sports', 'car', 'racer', 'and', 'convertible', 'with', 'the', 'proximities', 'of', '3175', '1864', 'and', '1345', 'respectfully', 'at', 'an', 'inference', 'time', 'of', '851ms']]
|
[-0.07590668257873724, 0.02812526038101436, -0.06880608873770518, 0.008592030303278828, -0.07508946193710846, -0.18204426312380853, 0.022060452111969317, 0.36835200970663745, -0.17046676138142014, -0.4058944439926349, 0.1482092045401634, -0.32537780580494335, -0.10565763462937491, 0.20024078534368206, -0.13569883442867328, 0.020792948345051094, 0.046227979683317245, 0.04902097235762459, 0.007582446199376136, -0.26182636818026794, 0.20617462327508668, 0.05804233091219109, 0.23380219675737487, -0.012329359949730775, 0.1192899769939044, 0.010284406819161686, -0.06591274857740193, -0.0447644152897684, -0.054778210262713185, 0.05542021636741565, 0.27835190029924406, 0.18449477233157, 0.2850992446244859, -0.4121110862559255, -0.10661644754184046, 0.015899376142838532, 0.08302813091808382, -0.018972797289846792, -0.0032770330784842373, -0.404510908278034, 0.10297909274494861, -0.2288240831838373, -0.06526465127193232, 0.04379541440592969, 0.05470844473593923, 0.0472187595852815, -0.19673724108074298, -0.013144286311067203, -0.029047928908702864, 0.15543806378674857, -0.06647754164056524, -0.11016671194092316, -0.05976013912107138, 0.22099536676233744, 0.025574089218314517, 0.05060099062496139, 0.16786718200070455, -0.09522926629425081, -0.12922707704608055, 0.3753878104281338, -0.0001035758075030411, -0.04553252347361515, 0.17830118347123702, -0.062212452741668506, -0.07572613582562875, 0.09426248759332606, 0.16908148049500168, 0.09892741337363772, -0.14590003054917736, 0.010914050728452447, -0.03262958087280447, 0.17224008087616632, 0.13171202171703472, -0.06749337593312649, 0.15592997551840895, 0.18792562903836368, -0.04163038627628018, 0.14338376941707204, -0.16714897591291983, -0.017212223762865454, -0.22613319294417605, -0.20976106963421712, -0.11579571718569187, 0.01576562227325185, -0.01986864676402868, -0.11261891670634641, 0.3871513628318687, 0.09501820040373679, 0.14211172649691647, 0.04333950561156277, 0.25384563317741543, 0.0032649486517424093, 0.11388781806727981, 0.1126028200290474, 0.1650959108627456, 0.016603905750055086, 0.2022130604203352, -0.12091435236746774, 0.04879124945522669, 0.03350461184266297]
|
1,803.07016
|
Solving coupled problems of lumped parameter models in a platform for
severe accidents in nuclear reactors
|
This paper focuses on solving coupled problems of lumped parameter models.
Such problems are of interest for the simulation of severe accidents in nuclear
reactors~: these coarse-grained models allow for fast calculations for
statistical analysis used for risk assessment and solutions of large problems
when considering the whole severe accident scenario. However, this modeling
approach has several numerical flaws. Besides, in this industrial context,
computational efficiency is of great importance leading to various numerical
constraints. The objective of this research is to analyze the applicability of
explicit coupling strategies to solve such coupled problems and to design
implicit coupling schemes allowing stable and accurate computations. The
proposed schemes are theoretically analyzed and tested within CEA's procor
platform on a problem of heat conduction solved with coupled lumped parameter
models and coupled 1D models. Numerical results are discussed and allow us to
emphasize the benefits of using the designed coupling schemes instead of the
usual explicit coupling schemes.
|
cs.CE physics.comp-ph
|
this paper focuses on solving coupled problems of lumped parameter models such problems are of interest for the simulation of severe accidents in nuclear reactors these coarsegrained models allow for fast calculations for statistical analysis used for risk assessment and solutions of large problems when considering the whole severe accident scenario however this modeling approach has several numerical flaws besides in this industrial context computational efficiency is of great importance leading to various numerical constraints the objective of this research is to analyze the applicability of explicit coupling strategies to solve such coupled problems and to design implicit coupling schemes allowing stable and accurate computations the proposed schemes are theoretically analyzed and tested within ceas procor platform on a problem of heat conduction solved with coupled lumped parameter models and coupled 1d models numerical results are discussed and allow us to emphasize the benefits of using the designed coupling schemes instead of the usual explicit coupling schemes
|
[['this', 'paper', 'focuses', 'on', 'solving', 'coupled', 'problems', 'of', 'lumped', 'parameter', 'models', 'such', 'problems', 'are', 'of', 'interest', 'for', 'the', 'simulation', 'of', 'severe', 'accidents', 'in', 'nuclear', 'reactors', 'these', 'coarsegrained', 'models', 'allow', 'for', 'fast', 'calculations', 'for', 'statistical', 'analysis', 'used', 'for', 'risk', 'assessment', 'and', 'solutions', 'of', 'large', 'problems', 'when', 'considering', 'the', 'whole', 'severe', 'accident', 'scenario', 'however', 'this', 'modeling', 'approach', 'has', 'several', 'numerical', 'flaws', 'besides', 'in', 'this', 'industrial', 'context', 'computational', 'efficiency', 'is', 'of', 'great', 'importance', 'leading', 'to', 'various', 'numerical', 'constraints', 'the', 'objective', 'of', 'this', 'research', 'is', 'to', 'analyze', 'the', 'applicability', 'of', 'explicit', 'coupling', 'strategies', 'to', 'solve', 'such', 'coupled', 'problems', 'and', 'to', 'design', 'implicit', 'coupling', 'schemes', 'allowing', 'stable', 'and', 'accurate', 'computations', 'the', 'proposed', 'schemes', 'are', 'theoretically', 'analyzed', 'and', 'tested', 'within', 'ceas', 'procor', 'platform', 'on', 'a', 'problem', 'of', 'heat', 'conduction', 'solved', 'with', 'coupled', 'lumped', 'parameter', 'models', 'and', 'coupled', '1d', 'models', 'numerical', 'results', 'are', 'discussed', 'and', 'allow', 'us', 'to', 'emphasize', 'the', 'benefits', 'of', 'using', 'the', 'designed', 'coupling', 'schemes', 'instead', 'of', 'the', 'usual', 'explicit', 'coupling', 'schemes']]
|
[-0.09188486738518502, 0.024447754917976756, -0.02308217087873998, 0.06187675014669553, -0.07465329224270625, -0.18572352507497925, 0.042695013036837995, 0.3546629339659539, -0.2404855996107635, -0.3201193528918502, 0.13532004929640187, -0.2415495092431322, -0.1305004037462939, 0.2637124747703544, -0.05204793866216324, 0.14411886215496522, 0.09288408238297471, -0.04643518629018217, -0.07686597225853266, -0.23580537461496603, 0.2861950569517481, 0.07041189728830105, 0.3173772976972545, 0.09506667074180232, 0.10159759383084467, -0.057382866605901375, -0.05622558526467914, 0.033535164864495016, -0.13972458097188606, 0.1489475149055346, 0.30888461598274614, 0.10176979649650793, 0.33273731533867806, -0.48734833222503465, -0.26294948457358164, 0.10443473540288277, 0.139890750474595, 0.11314719619724947, -0.054960874686889254, -0.24610285519455105, 0.046501998616478, -0.1863984264111003, -0.10929086839016049, -0.11944841737679851, -0.04904147906778141, 0.03384410963880304, -0.3092255881414391, 0.07608560278104284, -0.013729951810091734, 0.030984863233989485, -0.05511440319988208, -0.11021308595828043, 0.042546966013898596, 0.11165456026020155, 0.06917535053794265, -0.07636071209353992, 0.09816592456534123, -0.12534619415274414, -0.1288720573692654, 0.41462707105809105, -0.0014644982584286481, -0.2573196336847897, 0.2110503556815764, -0.011206064998614004, -0.14343211679265666, 0.10834171672244199, 0.2294233619587687, 0.14396967298540778, -0.14789238708134433, 0.09684312804855812, 0.03571408077214773, 0.14361980735198954, 0.0034045410396244665, -0.005759631528351934, 0.15372117661172524, 0.2363259132208231, 0.022933869921521712, 0.11640395297674844, -0.04512747788342098, -0.17290997136912595, -0.262202211799703, -0.0926440257991579, -0.11318708950271592, -0.03558943071626485, -0.09107547813600365, -0.1285168015374205, 0.3921815424453085, 0.23029079355406934, 0.09814178294096237, -0.0010353303275620325, 0.3406002340742793, 0.12170306911978584, 0.051269996459431685, 0.036695721035357565, 0.24398041766984627, 0.15002661163751513, 0.0934804667515728, -0.26057220575137013, 0.057695428057251356, 0.03619500769463439]
|
1,803.07017
|
A Positive Proportion of Hasse Principle Failures in a Family of
Ch\^atelet Surfaces
|
We investigate the family of surfaces defined by the affine equation $$Y^2 +
Z^2 = (aT^2 + b)(cT^2 +d)$$ where $\vert ad-bc \vert=1$ and develop an
asymptotic formula for the frequency of Hasse principle failures. We show that
a positive proportion (roughly 23.7%) of such surfaces fail the Hasse
principle, by building on previous work of la Bret\`{e}che and Browning.
|
math.NT math.AG
|
we investigate the family of surfaces defined by the affine equation y2 z2 at2 bct2 d where vert adbc vert1 and develop an asymptotic formula for the frequency of hasse principle failures we show that a positive proportion roughly 237 of such surfaces fail the hasse principle by building on previous work of la breteche and browning
|
[['we', 'investigate', 'the', 'family', 'of', 'surfaces', 'defined', 'by', 'the', 'affine', 'equation', 'y2', 'z2', 'at2', 'bct2', 'd', 'where', 'vert', 'adbc', 'vert1', 'and', 'develop', 'an', 'asymptotic', 'formula', 'for', 'the', 'frequency', 'of', 'hasse', 'principle', 'failures', 'we', 'show', 'that', 'a', 'positive', 'proportion', 'roughly', '237', 'of', 'such', 'surfaces', 'fail', 'the', 'hasse', 'principle', 'by', 'building', 'on', 'previous', 'work', 'of', 'la', 'breteche', 'and', 'browning']]
|
[-0.19668390176125936, 0.09620454398749903, -0.06858412728511862, 0.053509375978527327, -0.04807581349242745, -0.1469141659950505, 0.06261797059726502, 0.2564824250127588, -0.2520979279610661, -0.2736151360607307, 0.054392156739985306, -0.27669696094069096, -0.17972351931218458, 0.17358179337212018, -0.13319840131693386, 0.025266949519781128, -0.03470198250891242, 0.018602834124716798, -0.05471124358259009, -0.28488673475970117, 0.34510205978793757, -0.03306225793702262, 0.24952512785135436, 0.05259416250711573, 0.0986648373904505, 0.06597112348702337, 0.04234660289616191, -0.01749619355957423, -0.24294419533712894, 0.10534572729375213, 0.2562897446166192, 0.10274697774522272, 0.21301054492193675, -0.37129621407283203, -0.13944902404078416, 0.15941015943618758, 0.10504097055361074, 0.03582929497185562, -0.007658165407649774, -0.2504882354426497, 0.10835475556086749, -0.18189213638522364, -0.19687327755881207, -0.04195126332342625, 0.029501423372754028, 0.04900187643111816, -0.2358345221894394, 0.06841343044236835, 0.12662245336520886, 0.1268330887292645, -0.02325142068106548, -0.17678032742281044, -0.07432372698427311, 0.015663621390038834, 0.038076668844691346, 0.07052962164951689, 0.0019539621093177368, -0.038924266900201995, -0.1121829306440694, 0.31979986458463827, -0.09889324675480436, -0.14899088365824095, 0.08065490970121962, -0.14020366394210473, -0.17211219828043664, 0.08822968332762164, 0.11022432946733066, 0.1741744671682162, -0.07028948862197078, 0.16884845388579248, -0.053875103393303495, 0.09929686600974362, 0.09677283568972987, -0.04901694118702186, 0.13504502320263004, 0.037171357876754234, 0.04658564514206124, 0.04239518286859883, -0.06307276956587364, -0.002994887198188475, -0.3478910293030952, -0.21465752519101702, -0.16901877748646907, 0.14901567365242435, -0.10634364028425937, -0.15693958143570594, 0.2814289086298751, 0.07761182896241994, 0.2120280837937441, 0.14023452701180109, 0.14932589794105816, 0.09278683796791094, 0.00728036104036229, 0.08752465579891577, 0.15945765117482683, 0.14611037718610273, 0.0006210818703818534, -0.2123662267695181, 0.0686058390918853, 0.20715363955657398]
|
1,803.07018
|
Bayesian design of experiments for intractable likelihood models using
coupled auxiliary models and multivariate emulation
|
A Bayesian design is given by maximising an expected utility over a design
space. The utility is chosen to represent the aim of the experiment and its
expectation is taken with respect to all unknowns: responses, parameters and/or
models. Although straightforward in principle, there are several challenges to
finding Bayesian designs in practice. Firstly, the utility and expected utility
are rarely available in closed form and require approximation. Secondly, the
design space can be of high-dimensionality. In the case of intractable
likelihood models, these problems are compounded by the fact that the
likelihood function, whose evaluation is required to approximate the expected
utility, is not available in closed form. A strategy is proposed to find
Bayesian designs for intractable likelihood models. It relies on the
development of an automatic, auxiliary modelling approach, using multivariate
Gaussian process emulators, to approximate the likelihood function. This is
then combined with a copula-based approach to approximate the marginal
likelihood (a quantity commonly required to evaluate many utility functions).
These approximations are demonstrated on examples of stochastic process models
involving experimental aims of both parameter estimation and model comparison.
|
stat.ME
|
a bayesian design is given by maximising an expected utility over a design space the utility is chosen to represent the aim of the experiment and its expectation is taken with respect to all unknowns responses parameters andor models although straightforward in principle there are several challenges to finding bayesian designs in practice firstly the utility and expected utility are rarely available in closed form and require approximation secondly the design space can be of highdimensionality in the case of intractable likelihood models these problems are compounded by the fact that the likelihood function whose evaluation is required to approximate the expected utility is not available in closed form a strategy is proposed to find bayesian designs for intractable likelihood models it relies on the development of an automatic auxiliary modelling approach using multivariate gaussian process emulators to approximate the likelihood function this is then combined with a copulabased approach to approximate the marginal likelihood a quantity commonly required to evaluate many utility functions these approximations are demonstrated on examples of stochastic process models involving experimental aims of both parameter estimation and model comparison
|
[['a', 'bayesian', 'design', 'is', 'given', 'by', 'maximising', 'an', 'expected', 'utility', 'over', 'a', 'design', 'space', 'the', 'utility', 'is', 'chosen', 'to', 'represent', 'the', 'aim', 'of', 'the', 'experiment', 'and', 'its', 'expectation', 'is', 'taken', 'with', 'respect', 'to', 'all', 'unknowns', 'responses', 'parameters', 'andor', 'models', 'although', 'straightforward', 'in', 'principle', 'there', 'are', 'several', 'challenges', 'to', 'finding', 'bayesian', 'designs', 'in', 'practice', 'firstly', 'the', 'utility', 'and', 'expected', 'utility', 'are', 'rarely', 'available', 'in', 'closed', 'form', 'and', 'require', 'approximation', 'secondly', 'the', 'design', 'space', 'can', 'be', 'of', 'highdimensionality', 'in', 'the', 'case', 'of', 'intractable', 'likelihood', 'models', 'these', 'problems', 'are', 'compounded', 'by', 'the', 'fact', 'that', 'the', 'likelihood', 'function', 'whose', 'evaluation', 'is', 'required', 'to', 'approximate', 'the', 'expected', 'utility', 'is', 'not', 'available', 'in', 'closed', 'form', 'a', 'strategy', 'is', 'proposed', 'to', 'find', 'bayesian', 'designs', 'for', 'intractable', 'likelihood', 'models', 'it', 'relies', 'on', 'the', 'development', 'of', 'an', 'automatic', 'auxiliary', 'modelling', 'approach', 'using', 'multivariate', 'gaussian', 'process', 'emulators', 'to', 'approximate', 'the', 'likelihood', 'function', 'this', 'is', 'then', 'combined', 'with', 'a', 'copulabased', 'approach', 'to', 'approximate', 'the', 'marginal', 'likelihood', 'a', 'quantity', 'commonly', 'required', 'to', 'evaluate', 'many', 'utility', 'functions', 'these', 'approximations', 'are', 'demonstrated', 'on', 'examples', 'of', 'stochastic', 'process', 'models', 'involving', 'experimental', 'aims', 'of', 'both', 'parameter', 'estimation', 'and', 'model', 'comparison']]
|
[-0.058617491158656776, -0.006291603561808385, -0.06613151205744108, 0.10638559726456388, -0.11608328314184252, -0.1265626327316884, 0.05268206375299285, 0.4226842843320059, -0.26518396019958385, -0.32638476707412023, 0.12616397485164824, -0.24578720578701113, -0.1857726200073755, 0.21162819209047998, -0.09013981347063395, 0.13162625495707567, 0.0570491214824395, 0.01644733925754933, -0.07149627580150517, -0.28443469308094, 0.2903397093645965, 0.0872025936032119, 0.29874264917705895, -0.027134220611870936, 0.10118594592811701, 0.000993206792412346, -0.03649088374652859, 0.017251337634503296, -0.10925730802619396, 0.16014393356517362, 0.29695759053348686, 0.23131692498092257, 0.34561753974539106, -0.38929573043867055, -0.19719811737709475, 0.15280363078858025, 0.11993521672743752, 0.07347930416100375, -0.006059038347777222, -0.22430327100269293, 0.029990185584250394, -0.15944718158520435, -0.09359873493161538, -0.1127436254549969, -0.05093045118922854, 0.02432606327372765, -0.36952769687290443, 0.033071962395574105, -0.003327952667503901, 0.006602019997840019, -0.03227105694278852, -0.1493487710274918, 0.007916080929293379, 0.07587737555909173, 0.07066070175072958, 0.010329802851787384, 0.10340231386299306, -0.12569793689525124, -0.1289880018625611, 0.3501398669272337, -0.02243749961844119, -0.2819367521999242, 0.15648342812251623, -0.06384098466040324, -0.12157544638941307, 0.13974428067076192, 0.19710238884790274, 0.1270410488916399, -0.20357175953888698, 0.08300877216844009, -0.014876071943233357, 0.1431702774336926, -0.01575853346287698, -0.023703845596173778, 0.19435406730348326, 0.17919398098298267, 0.050796173603726937, 0.14140189333715092, -0.06497059144464362, -0.15042133798535517, -0.3021696214589452, -0.11882855940822755, -0.2220364230249644, -0.0032734413625407992, -0.09962027032230727, -0.18627561586807764, 0.34300534337323724, 0.21011596130278043, 0.1650365268566099, 0.11991919780848548, 0.3380810174756967, 0.16276084183229375, 0.04020517597066076, 0.05660128832855464, 0.21495316254541927, 0.0943009718852725, 0.018943174470737373, -0.16009741323574891, 0.16282956250032168, 0.00026042088385387933]
|
1,803.07019
|
Observation of Nuclear Quantum Effects and Hydrogen Bond Symmetrisation
in High Pressure Ice
|
Hydrogen bond symmetrisations in H-bonded systems triggered by pressure
induced nuclear quantum effects (NQEs) is a long-known concept1 but
experimental evidences in high-pressure ices have remained elusive with
conventional methods2,3. Theoretical works predicted quantum-mechanical
tunneling of protons within water ices to occur at pressures above 30 GPa and
the H-bond symmetrisation transition above 60 GPa4. Here, we used 1H-NMR on
high-pressure ice up to 90 GPa, and demonstrate that NQEs govern the behavior
of the hydrogen bonded protons in ice VII already at significantly lower
pressures than previously expected. A pronounced tunneling mode was found to be
present up to the highest pressures of 90 GPa, well into the stability field of
ice X, where NQEs are not anticipated in a fully symmetrized H-bond network. We
found two distinct transitions in the NMR shift data at about 20 GPa and 75 GPa
attributed to the step-wise symmetrization of the H-bond (HB), with
high-barrier H-Bonds (HBHB) to low-barrier H-bonds (LBHB) and LBHB to symmetric
H-bonds (SHB) respectively. These transitions could have major implication on
the physical properties of high-pressure ices and planetary interior models.
NQEs observed in this chemically simple system over a wide pressure range could
prove to be useful in designing a new generation of electronic devices
exploiting protonic tunneling.
|
cond-mat.mtrl-sci
|
hydrogen bond symmetrisations in hbonded systems triggered by pressure induced nuclear quantum effects nqes is a longknown concept1 but experimental evidences in highpressure ices have remained elusive with conventional methods23 theoretical works predicted quantummechanical tunneling of protons within water ices to occur at pressures above 30 gpa and the hbond symmetrisation transition above 60 gpa4 here we used 1hnmr on highpressure ice up to 90 gpa and demonstrate that nqes govern the behavior of the hydrogen bonded protons in ice vii already at significantly lower pressures than previously expected a pronounced tunneling mode was found to be present up to the highest pressures of 90 gpa well into the stability field of ice x where nqes are not anticipated in a fully symmetrized hbond network we found two distinct transitions in the nmr shift data at about 20 gpa and 75 gpa attributed to the stepwise symmetrization of the hbond hb with highbarrier hbonds hbhb to lowbarrier hbonds lbhb and lbhb to symmetric hbonds shb respectively these transitions could have major implication on the physical properties of highpressure ices and planetary interior models nqes observed in this chemically simple system over a wide pressure range could prove to be useful in designing a new generation of electronic devices exploiting protonic tunneling
|
[['hydrogen', 'bond', 'symmetrisations', 'in', 'hbonded', 'systems', 'triggered', 'by', 'pressure', 'induced', 'nuclear', 'quantum', 'effects', 'nqes', 'is', 'a', 'longknown', 'concept1', 'but', 'experimental', 'evidences', 'in', 'highpressure', 'ices', 'have', 'remained', 'elusive', 'with', 'conventional', 'methods23', 'theoretical', 'works', 'predicted', 'quantummechanical', 'tunneling', 'of', 'protons', 'within', 'water', 'ices', 'to', 'occur', 'at', 'pressures', 'above', '30', 'gpa', 'and', 'the', 'hbond', 'symmetrisation', 'transition', 'above', '60', 'gpa4', 'here', 'we', 'used', '1hnmr', 'on', 'highpressure', 'ice', 'up', 'to', '90', 'gpa', 'and', 'demonstrate', 'that', 'nqes', 'govern', 'the', 'behavior', 'of', 'the', 'hydrogen', 'bonded', 'protons', 'in', 'ice', 'vii', 'already', 'at', 'significantly', 'lower', 'pressures', 'than', 'previously', 'expected', 'a', 'pronounced', 'tunneling', 'mode', 'was', 'found', 'to', 'be', 'present', 'up', 'to', 'the', 'highest', 'pressures', 'of', '90', 'gpa', 'well', 'into', 'the', 'stability', 'field', 'of', 'ice', 'x', 'where', 'nqes', 'are', 'not', 'anticipated', 'in', 'a', 'fully', 'symmetrized', 'hbond', 'network', 'we', 'found', 'two', 'distinct', 'transitions', 'in', 'the', 'nmr', 'shift', 'data', 'at', 'about', '20', 'gpa', 'and', '75', 'gpa', 'attributed', 'to', 'the', 'stepwise', 'symmetrization', 'of', 'the', 'hbond', 'hb', 'with', 'highbarrier', 'hbonds', 'hbhb', 'to', 'lowbarrier', 'hbonds', 'lbhb', 'and', 'lbhb', 'to', 'symmetric', 'hbonds', 'shb', 'respectively', 'these', 'transitions', 'could', 'have', 'major', 'implication', 'on', 'the', 'physical', 'properties', 'of', 'highpressure', 'ices', 'and', 'planetary', 'interior', 'models', 'nqes', 'observed', 'in', 'this', 'chemically', 'simple', 'system', 'over', 'a', 'wide', 'pressure', 'range', 'could', 'prove', 'to', 'be', 'useful', 'in', 'designing', 'a', 'new', 'generation', 'of', 'electronic', 'devices', 'exploiting', 'protonic', 'tunneling']]
|
[-0.09323535171801957, 0.22919622002151405, -0.03485531705314095, 0.014600681011605719, -0.00032427203355501723, -0.12118213347756096, 0.12624972026560058, 0.4042448627861958, -0.2612506404871718, -0.3116210562242557, 0.01564427192189541, -0.2782466121298234, -0.09935338443226534, 0.1179900029222074, 0.035624123300489, 0.00012722307843273704, -0.010340437774537402, -0.02579433907239327, -0.08552016942531268, -0.21412325008926028, 0.22798108783532475, 0.09185155307663857, 0.26058305956613165, 0.14894722478048314, 0.03617831959346201, -0.09811928282035244, 0.10223789999907999, -0.010310230465284865, -0.17551065002273777, 0.030969082762134597, 0.2990161217440597, -0.0013104348611360692, 0.17445205881043327, -0.4569634765712092, -0.23299627516925045, 0.059363753443303545, 0.10894014468208606, 0.10861763551275165, -0.048718067980145364, -0.26997962905528045, 0.05867417393369799, -0.14708706435467145, -0.11682012782637562, -0.08209616944275218, 0.014838161571426046, -0.012162307726029414, -0.17995386120571655, 0.14052073820494115, 0.029579512664745337, 0.12129397950252717, -0.14180527905939494, -0.20378275611381344, -0.054988456952150516, -0.001036646210778396, -0.0026256060137332064, 0.039523645294536336, 0.23638631671512256, -0.07551094908515914, -0.08543330495465022, 0.42004271805991683, -0.03303754046816182, -0.001845937259540468, 0.23235372163228762, -0.20335105036891707, -0.13170029808658637, 0.262793402517558, 0.10427681151415827, 0.07143561053315847, -0.1569280075564872, -0.013409992948104401, 0.024503551244405685, 0.17698583427931913, 0.1268199511286034, 0.005505828695480251, 0.22641809177087638, 0.18188760648605876, 0.011475857670288374, 0.11247966276567646, -0.10360875145054096, -0.08698718686072716, -0.1686804774692011, -0.1783268366018039, -0.11371523609146977, 0.06882009012586475, -0.038647667780273835, -0.1219483161666114, 0.3141174149440683, 0.11445859887239351, 0.14426888254905137, -0.04301455895669613, 0.21222652173465462, 0.055346628458881116, 0.10904744807269098, 0.05407330903532074, 0.3033248337338344, 0.19988807186018676, 0.11690270523167695, -0.23788635936357733, 0.13862215609343959, -0.04384190517023332]
|
1,803.0702
|
An efficient algorithm for packing cuts and (2,3)-metrics in a planar
graph with three holes
|
We consider a planar graph $G$ in which the edges have nonnegative integer
lengths such that the length of every cycle of $G$ is even, and three faces are
distinguished, called holes in $G$. It is known that there exists a packing of
cuts and (2,3)-metrics with nonnegative integer weights in $G$ which realizes
the distances within each hole. We develop a strongly polynomial purely
combinatorial algorithm to find such a packing.
|
math.CO
|
we consider a planar graph g in which the edges have nonnegative integer lengths such that the length of every cycle of g is even and three faces are distinguished called holes in g it is known that there exists a packing of cuts and 23metrics with nonnegative integer weights in g which realizes the distances within each hole we develop a strongly polynomial purely combinatorial algorithm to find such a packing
|
[['we', 'consider', 'a', 'planar', 'graph', 'g', 'in', 'which', 'the', 'edges', 'have', 'nonnegative', 'integer', 'lengths', 'such', 'that', 'the', 'length', 'of', 'every', 'cycle', 'of', 'g', 'is', 'even', 'and', 'three', 'faces', 'are', 'distinguished', 'called', 'holes', 'in', 'g', 'it', 'is', 'known', 'that', 'there', 'exists', 'a', 'packing', 'of', 'cuts', 'and', '23metrics', 'with', 'nonnegative', 'integer', 'weights', 'in', 'g', 'which', 'realizes', 'the', 'distances', 'within', 'each', 'hole', 'we', 'develop', 'a', 'strongly', 'polynomial', 'purely', 'combinatorial', 'algorithm', 'to', 'find', 'such', 'a', 'packing']]
|
[-0.22496333967527032, 0.16419939240309553, -0.07074264182486165, 0.013645247244735209, -0.08374886865347204, -0.18785296223113235, 0.012823808964499285, 0.4120417251448396, -0.30028347602822414, -0.27198058775376893, 0.09260572152848447, -0.28697286971228225, -0.19926545446292615, 0.11933749893181761, -0.06486229365363612, -0.00805063646706477, 0.08203355568579175, 0.10918953175276098, -0.015060592559063774, -0.24591525205825848, 0.2823673260568733, -0.10710954309349328, 0.12959134565587616, 0.054331959192444323, 0.13672538257399114, 0.04390653465467859, 0.029664197923536872, 0.15634889588494535, -0.18977844285631953, 0.0636773620876418, 0.2893198730988087, 0.1335221615711778, 0.2673017186650508, -0.37078236510877133, -0.16306513374750042, 0.20139590676539434, 0.07671517476400125, 0.05110116179337279, -0.038452599197626114, -0.14315833201185918, 0.16328668311356345, -0.09319130653961444, -0.07083687280685129, 0.017790938386509955, 0.14493056043693928, -0.009474276158381516, -0.282628870779045, -0.0029379356272098882, 0.08084308732510873, -0.013274122973982717, 0.02839872030488832, -0.17720865780933642, -0.04241466477618251, 0.08312554295424004, -0.03562479583107092, 0.08879570372428902, 0.05912591411951851, -0.09234861630788992, -0.18160525496891686, 0.4094239966287999, -0.029552129569502785, -0.2095448150509365, 0.14994383616451645, -0.1566060908978254, -0.18168472042831946, 0.13468621403608524, 0.1327406077868712, 0.1578705001779845, -0.05455230111477595, 0.1351377024384163, -0.1585676279181326, 0.13929433102758837, 0.10714933295524351, 0.00903791119672463, 0.22777475849528547, 0.11945014969694992, 0.16369442308885634, 0.18459844138001053, -0.013655325948772296, 0.03228103932203122, -0.28206464909279433, -0.10723006676777568, -0.2570729029699373, 0.08373853440960528, -0.16749008138898538, -0.2518200771751958, 0.3765511781921689, 0.07091871975973563, 0.22500987583115487, 0.11238847902162709, 0.23132072299380474, 0.10301664613948112, 0.08696523287930381, 0.17303322962629544, 0.14692881566957688, 0.11840088114070273, -0.06445397794554929, -0.16677866030064686, 0.020325425726978083, 0.1461031996500744]
|
1,803.07021
|
Jumping VaR: Order Statistics Volatility Estimator for Jumps
Classification and Market Risk Modeling
|
This paper proposes a new integrated variance estimator based on order
statistics within the framework of jump-diffusion models. Its ability to
disentangle the integrated variance from the total process quadratic variation
is confirmed by both simulated and empirical tests. For practical purposes, we
introduce an iterative algorithm to estimate the time-varying volatility and
the occurred jumps of log-return time series. Such estimates enable the
definition of a new market risk model for the Value at Risk forecasting. We
show empirically that this procedure outperforms the standard historical
simulation method applying standard back-testing approach.
|
q-fin.RM
|
this paper proposes a new integrated variance estimator based on order statistics within the framework of jumpdiffusion models its ability to disentangle the integrated variance from the total process quadratic variation is confirmed by both simulated and empirical tests for practical purposes we introduce an iterative algorithm to estimate the timevarying volatility and the occurred jumps of logreturn time series such estimates enable the definition of a new market risk model for the value at risk forecasting we show empirically that this procedure outperforms the standard historical simulation method applying standard backtesting approach
|
[['this', 'paper', 'proposes', 'a', 'new', 'integrated', 'variance', 'estimator', 'based', 'on', 'order', 'statistics', 'within', 'the', 'framework', 'of', 'jumpdiffusion', 'models', 'its', 'ability', 'to', 'disentangle', 'the', 'integrated', 'variance', 'from', 'the', 'total', 'process', 'quadratic', 'variation', 'is', 'confirmed', 'by', 'both', 'simulated', 'and', 'empirical', 'tests', 'for', 'practical', 'purposes', 'we', 'introduce', 'an', 'iterative', 'algorithm', 'to', 'estimate', 'the', 'timevarying', 'volatility', 'and', 'the', 'occurred', 'jumps', 'of', 'logreturn', 'time', 'series', 'such', 'estimates', 'enable', 'the', 'definition', 'of', 'a', 'new', 'market', 'risk', 'model', 'for', 'the', 'value', 'at', 'risk', 'forecasting', 'we', 'show', 'empirically', 'that', 'this', 'procedure', 'outperforms', 'the', 'standard', 'historical', 'simulation', 'method', 'applying', 'standard', 'backtesting', 'approach']]
|
[-0.004980786628420314, -0.02730926005429493, -0.14305488810804423, 0.13721807175062822, -0.06943477299665252, -0.11503692195870943, 0.08141210538920976, 0.4105381577085423, -0.27504053151094787, -0.30586698484076286, 0.12894216529093683, -0.2561454381593453, -0.184143666746921, 0.24082877686978268, -0.12742178381160302, 0.09904399657088722, 0.060786134438208676, -0.024726436077867463, -0.025984545160705846, -0.2775987742784163, 0.23403361231409092, 0.09888453190765714, 0.3364382047651796, -0.007500910540662145, 0.16761113320206922, -0.002583469414422589, -0.08822322485002099, 0.01131407936198777, -0.12796829950594235, 0.1570996782211687, 0.2106134097800438, 0.16721372813567198, 0.3832743989452904, -0.3851033439359037, -0.19829780784665899, 0.14733333896685352, 0.07775773901131845, 0.052704076550560454, -0.02379222067638791, -0.28362467157984933, 0.023011235040812802, -0.22170280063554884, -0.10607633710418257, -0.1109905661314085, -0.0473000582618018, -0.0113583877282117, -0.3618665558376139, 0.13792192234447406, 0.008512683067550902, 0.04995684552047732, -0.05041645654672457, -0.13955561845232883, 0.049157413353602734, 0.07677025186218402, 0.09591776262862378, -0.04434039945694147, 0.1461240994613818, -0.03791824858936091, -0.17347863759164528, 0.30585213229861313, -0.11355800235140769, -0.1634590887334398, 0.11298069466275953, -0.09064212388869736, -0.13516073962373118, 0.10453983109885005, 0.2582423206298582, 0.07911503641435536, -0.21505825071951115, 0.05508673643337823, 0.015787806622283435, 0.1508229799788966, -0.027882934835869618, -0.053566772976429554, 0.14452930538845, 0.21881044867338353, 0.08430972284767577, 0.12873942158635585, -0.14470724539671054, -0.14037756914252875, -0.3217100680565401, -0.13776661488678185, -0.1769931494428586, -0.031127580440282743, -0.15088812651842462, -0.17876028462428278, 0.418177562895962, 0.2765175384589501, 0.14631729947543273, 0.1456339801110888, 0.3387900157380969, 0.1636028519921726, 0.0012570405479079933, 0.08613257404036259, 0.1591043555708502, 0.06134447166245551, 0.09775683627794346, -0.2047233631438826, 0.1583502745801603, 0.05112104412288435]
|
1,803.07022
|
The Feasibility and Benefits of In Situ Exploration of `Oumuamua-like
objects
|
A rapid accumulation of observations and interpretation have followed in the
wake of 1I `Oumuamua's passage through the inner Solar System. We briefly
outline the consequences that this first detection of an interstellar asteroid
implies for the planet-forming process, and we assess the near-term prospects
for detecting and observing (both remotely and in situ) future Solar System
visitors of this type. Drawing on detailed heat-transfer calculations that take
both `Oumuamua's unusual shape and its chaotic tumbling into account, we affirm
that the lack of a detectable coma in deep images of the object very likely
arises from the presence of a radiation-modified coating of high molecular
weight material (rather than a refractory bulk composition). Assuming that
`Oumuamua is a typical representative of a larger population with a kinematic
distribution similar to Population I stars in the local galactic neighborhood,
we calculate expected arrival rates, impact parameters and velocities of
similar objects and assess their prospects for detection using operational and
forthcoming facilities. Using `Oumuamua as a proof-of-concept, we assess the
prospects for missions that intercept interstellar objects (ISOs) using
conventional chemical propulsion. Using a "launch on detection" paradigm, we
estimate wait times of order 10 years between favorable mission opportunities
with the detection capabilities of the Large-Scale Synoptic Survey Telescope
(LSST), a figure that will be refined as the population of interstellar
asteroids becomes observationally better constrained.
|
astro-ph.EP
|
a rapid accumulation of observations and interpretation have followed in the wake of 1i oumuamuas passage through the inner solar system we briefly outline the consequences that this first detection of an interstellar asteroid implies for the planetforming process and we assess the nearterm prospects for detecting and observing both remotely and in situ future solar system visitors of this type drawing on detailed heattransfer calculations that take both oumuamuas unusual shape and its chaotic tumbling into account we affirm that the lack of a detectable coma in deep images of the object very likely arises from the presence of a radiationmodified coating of high molecular weight material rather than a refractory bulk composition assuming that oumuamua is a typical representative of a larger population with a kinematic distribution similar to population i stars in the local galactic neighborhood we calculate expected arrival rates impact parameters and velocities of similar objects and assess their prospects for detection using operational and forthcoming facilities using oumuamua as a proofofconcept we assess the prospects for missions that intercept interstellar objects isos using conventional chemical propulsion using a launch on detection paradigm we estimate wait times of order 10 years between favorable mission opportunities with the detection capabilities of the largescale synoptic survey telescope lsst a figure that will be refined as the population of interstellar asteroids becomes observationally better constrained
|
[['a', 'rapid', 'accumulation', 'of', 'observations', 'and', 'interpretation', 'have', 'followed', 'in', 'the', 'wake', 'of', '1i', 'oumuamuas', 'passage', 'through', 'the', 'inner', 'solar', 'system', 'we', 'briefly', 'outline', 'the', 'consequences', 'that', 'this', 'first', 'detection', 'of', 'an', 'interstellar', 'asteroid', 'implies', 'for', 'the', 'planetforming', 'process', 'and', 'we', 'assess', 'the', 'nearterm', 'prospects', 'for', 'detecting', 'and', 'observing', 'both', 'remotely', 'and', 'in', 'situ', 'future', 'solar', 'system', 'visitors', 'of', 'this', 'type', 'drawing', 'on', 'detailed', 'heattransfer', 'calculations', 'that', 'take', 'both', 'oumuamuas', 'unusual', 'shape', 'and', 'its', 'chaotic', 'tumbling', 'into', 'account', 'we', 'affirm', 'that', 'the', 'lack', 'of', 'a', 'detectable', 'coma', 'in', 'deep', 'images', 'of', 'the', 'object', 'very', 'likely', 'arises', 'from', 'the', 'presence', 'of', 'a', 'radiationmodified', 'coating', 'of', 'high', 'molecular', 'weight', 'material', 'rather', 'than', 'a', 'refractory', 'bulk', 'composition', 'assuming', 'that', 'oumuamua', 'is', 'a', 'typical', 'representative', 'of', 'a', 'larger', 'population', 'with', 'a', 'kinematic', 'distribution', 'similar', 'to', 'population', 'i', 'stars', 'in', 'the', 'local', 'galactic', 'neighborhood', 'we', 'calculate', 'expected', 'arrival', 'rates', 'impact', 'parameters', 'and', 'velocities', 'of', 'similar', 'objects', 'and', 'assess', 'their', 'prospects', 'for', 'detection', 'using', 'operational', 'and', 'forthcoming', 'facilities', 'using', 'oumuamua', 'as', 'a', 'proofofconcept', 'we', 'assess', 'the', 'prospects', 'for', 'missions', 'that', 'intercept', 'interstellar', 'objects', 'isos', 'using', 'conventional', 'chemical', 'propulsion', 'using', 'a', 'launch', 'on', 'detection', 'paradigm', 'we', 'estimate', 'wait', 'times', 'of', 'order', '10', 'years', 'between', 'favorable', 'mission', 'opportunities', 'with', 'the', 'detection', 'capabilities', 'of', 'the', 'largescale', 'synoptic', 'survey', 'telescope', 'lsst', 'a', 'figure', 'that', 'will', 'be', 'refined', 'as', 'the', 'population', 'of', 'interstellar', 'asteroids', 'becomes', 'observationally', 'better', 'constrained']]
|
[-0.10187671394952763, 0.1262115613497259, -0.08055035627253386, 0.07000406566868127, -0.08225902125437175, -0.0674061517942536, 0.06849014166066736, 0.38019428193668087, -0.2175055625415778, -0.34695947330354393, 0.1050339481871641, -0.2690881667573693, -0.11105461477171176, 0.21097459893290416, -0.053621970515788854, 0.014775121641969638, 0.11105505089724717, -0.05752673486646356, -0.05020477579787077, -0.21106139899940288, 0.24725393686377634, 0.1427134389470618, 0.17134636888729687, -0.004954347041831146, 0.07686246778178275, -0.04728687149513744, -0.0484860515040634, 0.00043590529203678657, -0.13773141978845563, 0.09983839210539035, 0.2186185288298628, 0.1728658790996842, 0.2419951407978542, -0.4380104634169061, -0.22379959840945635, 0.10011233835155556, 0.14100933799610796, 0.05181811775072618, -0.09939627916102949, -0.31158394824025276, 0.06309923498486415, -0.21561181501576068, -0.19425162000363214, -0.009330214489822118, 0.07540540315831014, 0.02770684713310257, -0.21611643614725465, 0.046250671202386934, 0.0047475689789280295, 0.09957276091035079, -0.12866308197427534, -0.1133395289699341, -0.023170381073069356, 0.12938782602210686, 0.01884079493509618, 0.007203157046455395, 0.18559224442970337, -0.17019195585981406, -0.05335729419144563, 0.42539605464934643, -0.08880382867338624, -0.04595828724126702, 0.2020501626317546, -0.19330765635488076, -0.15929773123741697, 0.11720847202499966, 0.20210648738301104, 0.12296805088382536, -0.15567685158542602, -0.006849110616882027, 0.0020773878889735293, 0.15247781498180454, 0.04066501778655529, 0.06452426114696515, 0.3061882060688747, 0.21047780693269671, 0.06896504919473247, 0.10425794278879329, -0.22578620768679653, -0.03434192715315725, -0.24893411547275243, -0.17474354992917351, -0.12989542922375938, 0.06397066593367969, -0.08463536350075074, -0.08814009965141922, 0.3698284505203004, 0.19662444788888683, 0.19399131566957792, 0.02724059898843082, 0.3162491119392546, 0.04102255701421208, 0.06615829932301479, 0.05737348420615514, 0.304735364204899, 0.0707155348716584, 0.0986917976370345, -0.2092177600175373, 0.13646931955820069, -0.016439038704343108]
|
1,803.07023
|
Space-filling branes & gaugings
|
We consider in any dimension the supersymmetric $\mathbb{Z}_2$ truncations of
the maximal supergravity theories. In each dimension and for each truncation we
determine all the sets of 1/2-BPS space-filling branes that preserve the
supersymmetry of the truncated theory and the representations of the symmetry
of such theory to which they belong. We show that in any dimension below eight
these sets always contain exotic branes, that are objects that do not have a
ten-dimensional origin. We repeat the same analysis for half-maximal theories
and for the quarter-maximal theories in four and three dimensions. We then
discuss all the possible gaugings of these theories as described in terms of
the embedding tensor. In general, the truncation acts on the quadratic
constraints of the embedding tensor in such a way that some representations
survive the truncation although they are not required by the supersymmetry of
the truncated theory. We show that for any theory, among these representations,
the highest-dimensional ones are precisely those of the 1/2-BPS space-filling
branes that preserve the same supersymmetry of the truncated theory, and we
interpret this result as the fact that these quadratic constraints after the
truncation become tadpole conditions for such branes.
|
hep-th
|
we consider in any dimension the supersymmetric mathbbz_2 truncations of the maximal supergravity theories in each dimension and for each truncation we determine all the sets of 12bps spacefilling branes that preserve the supersymmetry of the truncated theory and the representations of the symmetry of such theory to which they belong we show that in any dimension below eight these sets always contain exotic branes that are objects that do not have a tendimensional origin we repeat the same analysis for halfmaximal theories and for the quartermaximal theories in four and three dimensions we then discuss all the possible gaugings of these theories as described in terms of the embedding tensor in general the truncation acts on the quadratic constraints of the embedding tensor in such a way that some representations survive the truncation although they are not required by the supersymmetry of the truncated theory we show that for any theory among these representations the highestdimensional ones are precisely those of the 12bps spacefilling branes that preserve the same supersymmetry of the truncated theory and we interpret this result as the fact that these quadratic constraints after the truncation become tadpole conditions for such branes
|
[['we', 'consider', 'in', 'any', 'dimension', 'the', 'supersymmetric', 'mathbbz_2', 'truncations', 'of', 'the', 'maximal', 'supergravity', 'theories', 'in', 'each', 'dimension', 'and', 'for', 'each', 'truncation', 'we', 'determine', 'all', 'the', 'sets', 'of', '12bps', 'spacefilling', 'branes', 'that', 'preserve', 'the', 'supersymmetry', 'of', 'the', 'truncated', 'theory', 'and', 'the', 'representations', 'of', 'the', 'symmetry', 'of', 'such', 'theory', 'to', 'which', 'they', 'belong', 'we', 'show', 'that', 'in', 'any', 'dimension', 'below', 'eight', 'these', 'sets', 'always', 'contain', 'exotic', 'branes', 'that', 'are', 'objects', 'that', 'do', 'not', 'have', 'a', 'tendimensional', 'origin', 'we', 'repeat', 'the', 'same', 'analysis', 'for', 'halfmaximal', 'theories', 'and', 'for', 'the', 'quartermaximal', 'theories', 'in', 'four', 'and', 'three', 'dimensions', 'we', 'then', 'discuss', 'all', 'the', 'possible', 'gaugings', 'of', 'these', 'theories', 'as', 'described', 'in', 'terms', 'of', 'the', 'embedding', 'tensor', 'in', 'general', 'the', 'truncation', 'acts', 'on', 'the', 'quadratic', 'constraints', 'of', 'the', 'embedding', 'tensor', 'in', 'such', 'a', 'way', 'that', 'some', 'representations', 'survive', 'the', 'truncation', 'although', 'they', 'are', 'not', 'required', 'by', 'the', 'supersymmetry', 'of', 'the', 'truncated', 'theory', 'we', 'show', 'that', 'for', 'any', 'theory', 'among', 'these', 'representations', 'the', 'highestdimensional', 'ones', 'are', 'precisely', 'those', 'of', 'the', '12bps', 'spacefilling', 'branes', 'that', 'preserve', 'the', 'same', 'supersymmetry', 'of', 'the', 'truncated', 'theory', 'and', 'we', 'interpret', 'this', 'result', 'as', 'the', 'fact', 'that', 'these', 'quadratic', 'constraints', 'after', 'the', 'truncation', 'become', 'tadpole', 'conditions', 'for', 'such', 'branes']]
|
[-0.11161562232778241, 0.15385710617336326, -0.07099790118921262, 0.11710681218641977, -0.04210122000449934, -0.11409979026573591, -0.025649099620894934, 0.32634578227566985, -0.2158411950016251, -0.24479432887493227, 0.14356239762228842, -0.282888280820006, -0.18512088615829364, 0.11417172904162166, -0.07471122465884457, 0.005289746886596848, -0.013254274136553973, 0.0695032717480969, -0.11438141525394689, -0.3171445339930077, 0.36086694706374634, -0.057059572702751325, 0.22583480200801903, 0.007448812098934865, 0.0771745632050368, -0.021907111445967204, -0.005946328025311231, 0.030990460325772753, -0.1091791395459157, 0.14682999820185777, 0.22220702386485078, 0.13451792878003266, 0.13206660772005144, -0.4625356765034107, -0.22212827485532333, 0.13384590413397512, 0.17110117800677052, 0.14053914566488507, 0.012550304213968607, -0.23360160277822078, 0.13170864953874395, -0.17875335254730323, -0.1628729169543546, -0.12015913848359233, -0.0068420935541582415, -0.0498472546848158, -0.22923316322087955, 0.041446334085403345, 0.08450930097546333, 0.027894842767944704, -0.10658048828824973, -0.08677631080305824, -0.08741737995296717, 0.10781466959533878, 0.10081572871929846, -0.01296528718696955, 0.08555544206741242, -0.18867254090399888, -0.16079705192062718, 0.3714205380338125, -0.016820252842556397, -0.25104708758493266, 0.20495330778261026, -0.1665988802933731, -0.21289456002653026, 0.059576099881759055, 0.09790937316436799, 0.1620053906328021, -0.09421063776677235, 0.17510073749107483, -0.06738914317236497, 0.11820786038521104, 0.11687210242216213, 0.08699097906460221, 0.21907891140152247, 0.061805542174559566, 0.07681331556045617, 0.08890011273085689, -0.011522947826112311, -0.08820485138149263, -0.43633679509736023, -0.12414011752743345, -0.10558883951356014, 0.0627117108023809, -0.1552662084257463, -0.1923551602760712, 0.37729361880188567, 0.13709902451970638, 0.21090195162806852, 0.07976079315054589, 0.21074561923264692, 0.10672219960221974, 0.14383674278282202, 0.07069626477164909, 0.2433738487780106, 0.07345643093785606, 0.0020525922449544454, -0.2009454234210679, -0.07994919097385346, 0.1515192003072932]
|
1,803.07024
|
A note on vague convergence of measures
|
We propose a new approach to vague convergence of measures based on the
general theory of boundedness due to Hu (1966). The article explains how this
connects and unifies several frequently used types of vague convergence from
the literature. Such an approach allows one to translate already developed
results from one type of vague convergence to another. We further analyze the
corresponding notion of vague topology and give a new and useful
characterization of convergence in distribution of random measures in this
topology.
|
math.PR
|
we propose a new approach to vague convergence of measures based on the general theory of boundedness due to hu 1966 the article explains how this connects and unifies several frequently used types of vague convergence from the literature such an approach allows one to translate already developed results from one type of vague convergence to another we further analyze the corresponding notion of vague topology and give a new and useful characterization of convergence in distribution of random measures in this topology
|
[['we', 'propose', 'a', 'new', 'approach', 'to', 'vague', 'convergence', 'of', 'measures', 'based', 'on', 'the', 'general', 'theory', 'of', 'boundedness', 'due', 'to', 'hu', '1966', 'the', 'article', 'explains', 'how', 'this', 'connects', 'and', 'unifies', 'several', 'frequently', 'used', 'types', 'of', 'vague', 'convergence', 'from', 'the', 'literature', 'such', 'an', 'approach', 'allows', 'one', 'to', 'translate', 'already', 'developed', 'results', 'from', 'one', 'type', 'of', 'vague', 'convergence', 'to', 'another', 'we', 'further', 'analyze', 'the', 'corresponding', 'notion', 'of', 'vague', 'topology', 'and', 'give', 'a', 'new', 'and', 'useful', 'characterization', 'of', 'convergence', 'in', 'distribution', 'of', 'random', 'measures', 'in', 'this', 'topology']]
|
[-0.03966678851227983, 0.003465998732850954, -0.15788815728478492, 0.1293228736276323, -0.11278413233336017, -0.09800792838929288, 0.0871141985492186, 0.32075847534978963, -0.30520804563021087, -0.2525824740071815, 0.09216438640885234, -0.2279593649697953, -0.19154898039098964, 0.1911652760681169, -0.19412883186533328, 0.06773191021688013, 0.010307391505149833, 0.04261161161149033, -0.08635380951665252, -0.2357412454425301, 0.3558813288684441, 0.013682745643947497, 0.28788473878998355, 0.05625034145539604, 0.07346819131354611, 0.01810462586581707, -0.06557659185996437, 0.024636467329664045, -0.19513371379215674, 0.20390617375329406, 0.2027756784178586, 0.19799162925833608, 0.3340952775205474, -0.4143361305167158, -0.15979716065620264, 0.09160980735961573, 0.1273564245854785, 0.08709627146417477, -0.03312311940461801, -0.3015594956274313, 0.09232679592355726, -0.1577422878317849, -0.14261914102966528, -0.13848674645176134, -0.01714703375585826, 0.06566988399072764, -0.25083518802491295, 0.0501625009430909, 0.11116195432154506, 0.06119868255792612, -0.05777052432615647, -0.0826538455579991, 0.07110732693662755, 0.12264280339299016, 0.11419311987168818, 0.02769378307051059, 0.03822685867907053, -0.05690151312758764, -0.1598781140364078, 0.356699325413589, -0.031274809243987844, -0.20934700246350504, 0.2583785749753062, -0.11950719881668148, -0.2116024801283177, 0.07918421289019556, 0.17330492645816273, 0.14662211779392806, -0.1784173711595765, 0.07901345530920381, -0.030618577006171984, 0.11659504242061851, 0.0688307350052588, 0.07743192543570199, 0.12667409107313457, 0.17850473212325071, 0.11066043992941997, 0.16793189442110618, -0.029429217808913576, -0.12003284411684396, -0.30408052588442724, -0.1287091442731669, -0.1594824406980391, 0.04574390360068653, -0.08646218274970376, -0.20571454009602227, 0.4377901065556041, 0.242590130048703, 0.21512205880808544, 0.05252439754240843, 0.2440573418238032, 0.08012744622776308, -0.005680457744971815, 0.047133204549640775, 0.2037786962127829, 0.17406783594065403, 0.1312850974107453, -0.10504838700282824, 0.10592032956374607, 0.13418840644642688]
|
1,803.07025
|
Evidence from EXAFS for Different Ta/Ti Site Occupancy in High Critical
Current Density Nb$_3$Sn Superconductor Wires
|
To meet critical current density, J$_c$, targets for the Future Circular
Collider (FCC), the planned replacement for the Large Hadron Collider (LHC),
the high field performance of Nb$_3$Sn must be improved, but champion J$_c$
values have remained static for the last 10 years. Making the A15 phase
stoichiometric and enhancing the upper critical field H$_{c2}$ by Ti or Ta
dopants are the standard strategies for enhancing high field performance but
detailed recent studies show that even the best modern wires have broad
composition ranges. To assess whether further improvement might be possible, we
employed EXAFS to determine the lattice site location of dopants in modern
high-performance Nb$_3$Sn strands with J$_c$ values amongst the best so far
achieved. Although Ti and Ta primarily occupy the Nb sites in the A15
structure, we also find significant Ta occupancy on the Sn site. These findings
indicate that the best performing Ti-doped stand is strongly sub-stoichiometric
in Sn and that antisite disorder likely explains its high average H$_{c2}$
behavior. These new results suggest an important role for dopant and antisite
disorder in minimizing superconducting property distributions and maximizing
high field J$_c$ properties.
|
cond-mat.supr-con
|
to meet critical current density j_c targets for the future circular collider fcc the planned replacement for the large hadron collider lhc the high field performance of nb_3sn must be improved but champion j_c values have remained static for the last 10 years making the a15 phase stoichiometric and enhancing the upper critical field h_c2 by ti or ta dopants are the standard strategies for enhancing high field performance but detailed recent studies show that even the best modern wires have broad composition ranges to assess whether further improvement might be possible we employed exafs to determine the lattice site location of dopants in modern highperformance nb_3sn strands with j_c values amongst the best so far achieved although ti and ta primarily occupy the nb sites in the a15 structure we also find significant ta occupancy on the sn site these findings indicate that the best performing tidoped stand is strongly substoichiometric in sn and that antisite disorder likely explains its high average h_c2 behavior these new results suggest an important role for dopant and antisite disorder in minimizing superconducting property distributions and maximizing high field j_c properties
|
[['to', 'meet', 'critical', 'current', 'density', 'j_c', 'targets', 'for', 'the', 'future', 'circular', 'collider', 'fcc', 'the', 'planned', 'replacement', 'for', 'the', 'large', 'hadron', 'collider', 'lhc', 'the', 'high', 'field', 'performance', 'of', 'nb_3sn', 'must', 'be', 'improved', 'but', 'champion', 'j_c', 'values', 'have', 'remained', 'static', 'for', 'the', 'last', '10', 'years', 'making', 'the', 'a15', 'phase', 'stoichiometric', 'and', 'enhancing', 'the', 'upper', 'critical', 'field', 'h_c2', 'by', 'ti', 'or', 'ta', 'dopants', 'are', 'the', 'standard', 'strategies', 'for', 'enhancing', 'high', 'field', 'performance', 'but', 'detailed', 'recent', 'studies', 'show', 'that', 'even', 'the', 'best', 'modern', 'wires', 'have', 'broad', 'composition', 'ranges', 'to', 'assess', 'whether', 'further', 'improvement', 'might', 'be', 'possible', 'we', 'employed', 'exafs', 'to', 'determine', 'the', 'lattice', 'site', 'location', 'of', 'dopants', 'in', 'modern', 'highperformance', 'nb_3sn', 'strands', 'with', 'j_c', 'values', 'amongst', 'the', 'best', 'so', 'far', 'achieved', 'although', 'ti', 'and', 'ta', 'primarily', 'occupy', 'the', 'nb', 'sites', 'in', 'the', 'a15', 'structure', 'we', 'also', 'find', 'significant', 'ta', 'occupancy', 'on', 'the', 'sn', 'site', 'these', 'findings', 'indicate', 'that', 'the', 'best', 'performing', 'tidoped', 'stand', 'is', 'strongly', 'substoichiometric', 'in', 'sn', 'and', 'that', 'antisite', 'disorder', 'likely', 'explains', 'its', 'high', 'average', 'h_c2', 'behavior', 'these', 'new', 'results', 'suggest', 'an', 'important', 'role', 'for', 'dopant', 'and', 'antisite', 'disorder', 'in', 'minimizing', 'superconducting', 'property', 'distributions', 'and', 'maximizing', 'high', 'field', 'j_c', 'properties']]
|
[-0.10263991749478861, 0.17517396786191036, 0.02512142052031816, 0.055502410371852245, -0.051182572852493204, -0.1802455212678166, 0.11967228228279558, 0.4331979139242321, -0.2100707445580988, -0.3013153459128745, 0.04239631528183421, -0.33806092836993173, -0.06097140881366671, 0.18557755871300655, 0.024425162324444093, 0.0204053005348195, 0.039443926981704784, -0.036997038859903734, -0.09218109692626464, -0.32354699191018105, 0.2438308626662276, 0.14635353361533837, 0.3799642876813565, 0.11296074617603928, -0.020408975493294148, -0.02449341422997098, 0.07764966667758579, 0.05462196744245259, -0.1505953985384583, 0.06794168040002485, 0.29013252645939036, 0.03142226429438179, 0.19491774781651677, -0.4467513938087653, -0.1925601593641059, 0.06822873590553695, 0.14387153384790935, 0.08525738796897907, -0.0694293510843752, -0.23233317884002277, 0.11868411045523974, -0.13084169693211925, -0.1340582573345486, -0.06152122795391095, 0.008937733755645124, 0.039952996285060084, -0.24249404532484403, 0.03980416149762335, 0.027791447855750138, 0.14024397580586548, -0.07460921667231385, -0.23782634850160436, -0.04501835743530079, 0.07152549927884544, 0.05058358666521715, 0.07705194530810447, 0.18654330687329887, -0.15178686888403, -0.09438691134911348, 0.3171569615716432, -0.029286560364701647, -0.04758181563266454, 0.17652439552190852, -0.21159617288720525, -0.13659987142904007, 0.13913642186696265, 0.1100498186820682, 0.049662882833682157, -0.12017393618991767, 0.07792248963062562, 0.028927853090708402, 0.19673814305272747, 0.03280028258202637, 0.06469438479906146, 0.24435818816307298, 0.22239418559029026, 0.08492640092067341, 0.05850673957784819, -0.12203782151745474, -0.0180549144691, -0.21660540847385185, -0.19757565856970688, -0.17052266301408886, 0.03860650569673608, -0.10593288716018891, -0.15849989592939853, 0.3264401276481952, 0.17859264259211757, 0.19642524508898088, -0.06504928158407912, 0.19921982721326517, 0.0751561451420941, 0.10111615151331631, 0.042565600768671656, 0.3048875124733697, 0.10666118409271609, 0.13598364889107772, -0.2248455668586564, 0.138271191564235, -0.012958869711121921]
|
1,803.07026
|
New superexchange paths due to breathing-enhanced hopping in
corner-sharing cuprates
|
We present ab initio calculations of the superexchange antiferromagnetic spin
coupling $J$ for two cuprates, Sr$_2$CuO$_3$ and La$_2$CuO$_4$. Good agreement
with experimental estimates is obtained. We find that $J$ increases
substantially as the distance between Cu and apical O is increased. There is an
important synergetic effect of the Coulomb interaction, expanding the Cu $3d$
orbital when an electron hops into this orbital, and the O-Cu hopping, being
increased by this orbital expansion (breathing). This is a new ingredient in
superexchange models. In a model with a fixed basis, breathing effects can be
described as a mixing of $3d$ and $4d$ orbitals or as a single $3d \to 4d$
excitation.
|
cond-mat.str-el
|
we present ab initio calculations of the superexchange antiferromagnetic spin coupling j for two cuprates sr_2cuo_3 and la_2cuo_4 good agreement with experimental estimates is obtained we find that j increases substantially as the distance between cu and apical o is increased there is an important synergetic effect of the coulomb interaction expanding the cu 3d orbital when an electron hops into this orbital and the ocu hopping being increased by this orbital expansion breathing this is a new ingredient in superexchange models in a model with a fixed basis breathing effects can be described as a mixing of 3d and 4d orbitals or as a single 3d to 4d excitation
|
[['we', 'present', 'ab', 'initio', 'calculations', 'of', 'the', 'superexchange', 'antiferromagnetic', 'spin', 'coupling', 'j', 'for', 'two', 'cuprates', 'sr_2cuo_3', 'and', 'la_2cuo_4', 'good', 'agreement', 'with', 'experimental', 'estimates', 'is', 'obtained', 'we', 'find', 'that', 'j', 'increases', 'substantially', 'as', 'the', 'distance', 'between', 'cu', 'and', 'apical', 'o', 'is', 'increased', 'there', 'is', 'an', 'important', 'synergetic', 'effect', 'of', 'the', 'coulomb', 'interaction', 'expanding', 'the', 'cu', '3d', 'orbital', 'when', 'an', 'electron', 'hops', 'into', 'this', 'orbital', 'and', 'the', 'ocu', 'hopping', 'being', 'increased', 'by', 'this', 'orbital', 'expansion', 'breathing', 'this', 'is', 'a', 'new', 'ingredient', 'in', 'superexchange', 'models', 'in', 'a', 'model', 'with', 'a', 'fixed', 'basis', 'breathing', 'effects', 'can', 'be', 'described', 'as', 'a', 'mixing', 'of', '3d', 'and', '4d', 'orbitals', 'or', 'as', 'a', 'single', '3d', 'to', '4d', 'excitation']]
|
[-0.14562650308987007, 0.19075642749608426, 0.01325301797804209, 0.04898177468059841, -0.009895360615283866, -0.16537166493218564, 0.05754231375112378, 0.39241359047933455, -0.2528219152276122, -0.28503582192533605, -0.04542472060778341, -0.3436088075545198, -0.12198021724486911, 0.12457766869412991, 0.05142978454914388, -0.05322560371506378, 0.062164020417001815, -0.056087495015780316, -0.1263936923607466, -0.1856065408770986, 0.2394504831770623, 0.08512930119188007, 0.22470056523468535, 0.07349044765952394, 0.015248401193033665, 0.05903275636208474, 0.08929123919523416, 0.019174730751253324, -0.1540083231465435, 0.13233118554696852, 0.24083018440683399, -0.039926306532542095, 0.21262165886956616, -0.4278831044468311, -0.20438955007377294, -0.03626244206306174, 0.20037423286997125, 0.1838203046419882, -0.0589399923006534, -0.25376068206862845, -0.024864376625131576, -0.20065822210504647, -0.10130768098041774, -0.0944378391984816, 0.06095831591952079, -0.0017417576377613282, -0.3582192717820679, 0.10777661342327612, 0.05736440939854386, 0.11435508697421595, -0.11841459217301886, -0.12573046479886824, -0.12943380913022187, 0.08817181509087468, 0.07029392065185575, 0.15831149075342632, 0.06910799993971072, -0.07790015223265173, -0.11271709381013152, 0.4072951389767161, -0.05728894263215431, -0.15565391778604154, 0.18547816847562107, -0.15482207858647165, -0.061460860930393886, 0.12634937201173754, 0.06727834523510222, 0.08838050539067033, -0.110382422000205, 0.08691707211809602, -0.017150145737505562, 0.19585589351615262, -0.002195100872478354, 0.03349317161203736, 0.22461257161094098, 0.19839825618525095, 0.02320904710218994, 0.09334150688838078, -0.14962919841631564, -0.0684365637497891, -0.2222006620514557, -0.1578527309765202, -0.24967568747938498, 0.06666205419919564, -0.10838924665719596, -0.16061275155035729, 0.36886906073083714, 0.12986470406678496, 0.19845593037348616, -0.06782807214100153, 0.2329548312641612, 0.10579083861736154, 0.06189341570139615, 0.020330636710817113, 0.26619583468696256, 0.1185702416605803, 0.06707650967318257, -0.3067977316164916, 0.05249879884730102, 0.07885172325314595]
|
1,803.07027
|
Brownian Motions on Star Graphs with Non-Local Boundary Conditions
|
Brownian motions on star graphs in the sense of It\^o-McKean, that is, Walsh
processes admitting a generalized boundary behavior including stickiness and
jumps and having an angular distribution with finite support, are examined.
Their generators are identified as Laplace operators on the graph subject to
non-local Feller-Wentzell boundary conditions. A pathwise description is
achieved for every admissible boundary condition: For finite jump measures, a
construction of Kostrykin, Potthoff and Schrader in the continuous setting is
expanded via a technique of successive killings and revivals; for infinite jump
measures, the pathwise solution of It\^o-McKean for the half line is analyzed
and extended to the star graph. These processes can then be used as main
building blocks for Brownian motions on general metric graphs with non-local
boundary conditions.
|
math.PR
|
brownian motions on star graphs in the sense of itomckean that is walsh processes admitting a generalized boundary behavior including stickiness and jumps and having an angular distribution with finite support are examined their generators are identified as laplace operators on the graph subject to nonlocal fellerwentzell boundary conditions a pathwise description is achieved for every admissible boundary condition for finite jump measures a construction of kostrykin potthoff and schrader in the continuous setting is expanded via a technique of successive killings and revivals for infinite jump measures the pathwise solution of itomckean for the half line is analyzed and extended to the star graph these processes can then be used as main building blocks for brownian motions on general metric graphs with nonlocal boundary conditions
|
[['brownian', 'motions', 'on', 'star', 'graphs', 'in', 'the', 'sense', 'of', 'itomckean', 'that', 'is', 'walsh', 'processes', 'admitting', 'a', 'generalized', 'boundary', 'behavior', 'including', 'stickiness', 'and', 'jumps', 'and', 'having', 'an', 'angular', 'distribution', 'with', 'finite', 'support', 'are', 'examined', 'their', 'generators', 'are', 'identified', 'as', 'laplace', 'operators', 'on', 'the', 'graph', 'subject', 'to', 'nonlocal', 'fellerwentzell', 'boundary', 'conditions', 'a', 'pathwise', 'description', 'is', 'achieved', 'for', 'every', 'admissible', 'boundary', 'condition', 'for', 'finite', 'jump', 'measures', 'a', 'construction', 'of', 'kostrykin', 'potthoff', 'and', 'schrader', 'in', 'the', 'continuous', 'setting', 'is', 'expanded', 'via', 'a', 'technique', 'of', 'successive', 'killings', 'and', 'revivals', 'for', 'infinite', 'jump', 'measures', 'the', 'pathwise', 'solution', 'of', 'itomckean', 'for', 'the', 'half', 'line', 'is', 'analyzed', 'and', 'extended', 'to', 'the', 'star', 'graph', 'these', 'processes', 'can', 'then', 'be', 'used', 'as', 'main', 'building', 'blocks', 'for', 'brownian', 'motions', 'on', 'general', 'metric', 'graphs', 'with', 'nonlocal', 'boundary', 'conditions']]
|
[-0.13663110159160125, 0.12985331513690263, -0.10941820427228416, 0.07246281040669789, -0.10903278694281147, -0.12061794265080983, 0.016219073411313786, 0.386147399743398, -0.24321313190554816, -0.2056989426695047, 0.1641730685138129, -0.252375236808485, -0.11062364050349782, 0.1853957704844929, -0.10427069193535736, 0.08817048972132542, 0.08163463151348489, 0.0413854623043407, -0.025063807715750522, -0.20961645691579814, 0.3288528219619322, -0.026236568973954058, 0.2116843339587961, 0.04550708970008788, 0.1485798325905177, -0.012875762308578401, -0.04572635453604605, 0.041117019729600066, -0.16562114249563098, 0.0643552024516144, 0.21836516779056558, 0.06253954430761201, 0.24967293357033105, -0.3928132789929689, -0.21688411000442492, 0.11396208555171532, 0.10698263707851606, 0.03290994323435284, 0.009864103678236938, -0.3261373879328843, 0.07077657827915299, -0.11290011604848717, -0.15377009425696636, -0.04545545954966829, 0.05724779908944454, 0.052451542724618716, -0.31548931526338003, 0.0735035183625148, 0.11224341284232361, 0.06630109879373026, -0.06608708903917836, -0.07683238001181818, -0.051078279262467746, 0.09527467027868307, -0.010785798253935008, 0.0017602711413351316, 0.10670814378277606, -0.06321126277307196, -0.15886280832106306, 0.35343979612465887, -0.07598261481949262, -0.2700497075316629, 0.18137294029085232, -0.14365895801696868, -0.13174836180867658, 0.11863801949509671, 0.1288083965505754, 0.1330048521529765, -0.18778226060408448, 0.10405306162133385, -0.017660449569423992, 0.05451339636633675, 0.12175094461925919, 0.026837744312601105, 0.1399982520231297, 0.10803941179931696, 0.15417704112746472, 0.16496807007795378, -0.007220038562081754, -0.1490327770459569, -0.3486752235700214, -0.1491405829791412, -0.18478741687870334, 0.06116487855269086, -0.1510063776563223, -0.23018862103899232, 0.33644021876777214, 0.07063603023111466, 0.17435498523067625, 0.08427424657542909, 0.17491912501790222, 0.15828393075415598, 0.03261510272715809, 0.08892154282269378, 0.10611047593152358, 0.19272733730862715, 0.07885716288417045, -0.17712956951147626, 0.07887385133653879, 0.14509262011889074]
|
1,803.07028
|
Speckle characterization in a cinematography projection configuration
|
Due to high exploitation costs and other environmental issues, it would be
desirable to phase out large cinema projection systems based on standard xenon
lamps in favor of laser based projection devices. Lasers provide longer
lifetime and wider color gamut of light output. But the high degree of
coherence of these sources also lead to the formation of granular structures,
usually known as speckle. When an imaging system is involved, as in the cinema
projection case because of the capacity of the human eye to form an image of
the screen, we speak about subjective speckle. In order to remove this spatial
random pattern, different methods have been studied as temporal and/or spatial
coherence reduction. But most of them can't be used in the context of cinema
projection because they don't respect the cinematography projection standard.
In our work, we have studied the possibility to reduce the subjective speckle
either by changing the coherence of the light source or by studying the
influence of the different elements constituting the projection display in the
conditions imposed by cinematography industry. Thanks to a lasers array formed
by N independant semiconductor lasers, we have measured the evolution of the
subjective speckle contrast in function of the number of sources. The resulting
contrast discreases as a square root function and reach a saturation level when
a light pipe is used. This behavior is directly due to the light pipe which
limit at its output the spatial coherence of the source. Futhermore, in a
different configuration, we have studied the influence of diffusers and the
magnification of the projector zoom. It has been demonstrated that
magnification plays an important role on the speckle formation because it
increases the coherence length determined by the light pipe. On the contrary,
the diffusers placed before the light pipe doesn't change the subjective
speckle.
|
physics.app-ph
|
due to high exploitation costs and other environmental issues it would be desirable to phase out large cinema projection systems based on standard xenon lamps in favor of laser based projection devices lasers provide longer lifetime and wider color gamut of light output but the high degree of coherence of these sources also lead to the formation of granular structures usually known as speckle when an imaging system is involved as in the cinema projection case because of the capacity of the human eye to form an image of the screen we speak about subjective speckle in order to remove this spatial random pattern different methods have been studied as temporal andor spatial coherence reduction but most of them cant be used in the context of cinema projection because they dont respect the cinematography projection standard in our work we have studied the possibility to reduce the subjective speckle either by changing the coherence of the light source or by studying the influence of the different elements constituting the projection display in the conditions imposed by cinematography industry thanks to a lasers array formed by n independant semiconductor lasers we have measured the evolution of the subjective speckle contrast in function of the number of sources the resulting contrast discreases as a square root function and reach a saturation level when a light pipe is used this behavior is directly due to the light pipe which limit at its output the spatial coherence of the source futhermore in a different configuration we have studied the influence of diffusers and the magnification of the projector zoom it has been demonstrated that magnification plays an important role on the speckle formation because it increases the coherence length determined by the light pipe on the contrary the diffusers placed before the light pipe doesnt change the subjective speckle
|
[['due', 'to', 'high', 'exploitation', 'costs', 'and', 'other', 'environmental', 'issues', 'it', 'would', 'be', 'desirable', 'to', 'phase', 'out', 'large', 'cinema', 'projection', 'systems', 'based', 'on', 'standard', 'xenon', 'lamps', 'in', 'favor', 'of', 'laser', 'based', 'projection', 'devices', 'lasers', 'provide', 'longer', 'lifetime', 'and', 'wider', 'color', 'gamut', 'of', 'light', 'output', 'but', 'the', 'high', 'degree', 'of', 'coherence', 'of', 'these', 'sources', 'also', 'lead', 'to', 'the', 'formation', 'of', 'granular', 'structures', 'usually', 'known', 'as', 'speckle', 'when', 'an', 'imaging', 'system', 'is', 'involved', 'as', 'in', 'the', 'cinema', 'projection', 'case', 'because', 'of', 'the', 'capacity', 'of', 'the', 'human', 'eye', 'to', 'form', 'an', 'image', 'of', 'the', 'screen', 'we', 'speak', 'about', 'subjective', 'speckle', 'in', 'order', 'to', 'remove', 'this', 'spatial', 'random', 'pattern', 'different', 'methods', 'have', 'been', 'studied', 'as', 'temporal', 'andor', 'spatial', 'coherence', 'reduction', 'but', 'most', 'of', 'them', 'cant', 'be', 'used', 'in', 'the', 'context', 'of', 'cinema', 'projection', 'because', 'they', 'dont', 'respect', 'the', 'cinematography', 'projection', 'standard', 'in', 'our', 'work', 'we', 'have', 'studied', 'the', 'possibility', 'to', 'reduce', 'the', 'subjective', 'speckle', 'either', 'by', 'changing', 'the', 'coherence', 'of', 'the', 'light', 'source', 'or', 'by', 'studying', 'the', 'influence', 'of', 'the', 'different', 'elements', 'constituting', 'the', 'projection', 'display', 'in', 'the', 'conditions', 'imposed', 'by', 'cinematography', 'industry', 'thanks', 'to', 'a', 'lasers', 'array', 'formed', 'by', 'n', 'independant', 'semiconductor', 'lasers', 'we', 'have', 'measured', 'the', 'evolution', 'of', 'the', 'subjective', 'speckle', 'contrast', 'in', 'function', 'of', 'the', 'number', 'of', 'sources', 'the', 'resulting', 'contrast', 'discreases', 'as', 'a', 'square', 'root', 'function', 'and', 'reach', 'a', 'saturation', 'level', 'when', 'a', 'light', 'pipe', 'is', 'used', 'this', 'behavior', 'is', 'directly', 'due', 'to', 'the', 'light', 'pipe', 'which', 'limit', 'at', 'its', 'output', 'the', 'spatial', 'coherence', 'of', 'the', 'source', 'futhermore', 'in', 'a', 'different', 'configuration', 'we', 'have', 'studied', 'the', 'influence', 'of', 'diffusers', 'and', 'the', 'magnification', 'of', 'the', 'projector', 'zoom', 'it', 'has', 'been', 'demonstrated', 'that', 'magnification', 'plays', 'an', 'important', 'role', 'on', 'the', 'speckle', 'formation', 'because', 'it', 'increases', 'the', 'coherence', 'length', 'determined', 'by', 'the', 'light', 'pipe', 'on', 'the', 'contrary', 'the', 'diffusers', 'placed', 'before', 'the', 'light', 'pipe', 'doesnt', 'change', 'the', 'subjective', 'speckle']]
|
[-0.07571673643695631, 0.1278342970347359, -0.09906223855643093, 0.048883070377709566, -0.03152202969144319, -0.11020943391179715, 0.01047314250938239, 0.40648643471803025, -0.2647818191929362, -0.31059335773649144, 0.1174587381675864, -0.2617127148091401, -0.10963874487252294, 0.17907255437335393, -0.09670595605716938, 0.06750843718902233, 0.030604554119283995, 0.018021527818793976, -0.04805698489891304, -0.24374781999511852, 0.2939802640068688, 0.08414810193292062, 0.31765340425542826, 0.03545102288588073, 0.10427664382204009, 0.025335725285817477, -0.05249852551711037, 0.009036209878487219, -0.05981836374171747, 0.08416120934845439, 0.2134984820226428, 0.10748525401983275, 0.2683820128823802, -0.4405781389030285, -0.23089422705647608, 0.10480824823982977, 0.14341520175864725, 0.09115229594394086, -0.043017709427084286, -0.29768883528442147, 0.04902931600027889, -0.11634273401666992, -0.1241456031420488, -0.0159764080446238, 0.01228190961812384, 0.03909038591212409, -0.20644306369266766, 0.02322657790414508, 0.054294298917643334, 0.0762758641365891, -0.0047565058755361335, -0.09690761981389522, -0.0019337333651492372, 0.1452723505639082, 0.04568989810880004, 0.056109057049788566, 0.1553687833381302, -0.16977655038384623, -0.0652966953700678, 0.3972909271718603, -0.04252992459920566, -0.1864671607670875, 0.18740004167653082, -0.17358667776141756, -0.0659090681619043, 0.1544555107921999, 0.16886581066118148, 0.08983475119978386, -0.11866071856150627, 0.00842767412464845, -0.005115929510027759, 0.2141839312458423, 0.12788720376250384, 0.11354771770052857, 0.22358427831510963, 0.18628806859372785, 0.05054093800074617, 0.13009629634076478, -0.14874650634613462, -0.07123053211360361, -0.23161263890123288, -0.130832912469295, -0.1812844341130633, 0.034539580551944185, -0.0666378129434107, -0.14429108809111457, 0.3672332501791013, 0.16946850388883736, 0.17613980551667688, -0.02565023534369079, 0.31290613868891104, 0.10733684999018135, 0.12245972560432213, 0.0022256519749039158, 0.2618680574002945, 0.11016482203903204, 0.14297528699994713, -0.24060763877136387, 0.09957864351523121, -0.005405350118771342]
|
1,803.07029
|
A black market for upvotes and likes
|
Purpose: This research investigates controversial online marketing techniques
that involve buying hundreds or even thousands of upvotes, likes, comments,
etc.
Methodology: Observation and categorization of 7,426 campaigns posted on the
crowdsourcing platform microworkers.com over a 365 day (i.e., yearlong) period
were conducted. Hypotheses about the mechanics and effectiveness of these
campaigns were established and evaluated.
Findings: The campaigns contained a combined 1,856,316 microtasks, 89.7% of
which were connected to online promotion. Techniques for search engine
manipulation, comment-generating in the scale of tens of thousands, online vote
manipulation, mass account creation, methods for covering tracks were
discovered. The article presents an assessment of the effectiveness of such
campaigns as well as various security challenges created by these campaigns.
Research limitations: The observed campaigns form only a small portion of the
overall "black market". This is due to invite-only campaigns and the presence
of alternative, unobservable platforms.
Practical implications: The findings of this article could be input for
detecting and avoiding such online campaigns.
Social implications: The findings show that in some conditions tremendous
levels of manipulation of an online discourse can be achieved with a limited
budget.
Originality: While there is related work on "follower factories" and
"click/troll farms", those entities offer complete "solutions" and their
techniques are rather opaque. By investigating a crowdsourcing platform, this
research unveils the underlying mechanics and organization of such campaigns.
The research is based on a uniquely large number of observations. Small, cheap
campaigns, the manipulation of less significant platforms is also included,
while the related work tends to focus on mass, politically motivated efforts.
|
cs.CY
|
purpose this research investigates controversial online marketing techniques that involve buying hundreds or even thousands of upvotes likes comments etc methodology observation and categorization of 7426 campaigns posted on the crowdsourcing platform microworkerscom over a 365 day ie yearlong period were conducted hypotheses about the mechanics and effectiveness of these campaigns were established and evaluated findings the campaigns contained a combined 1856316 microtasks 897 of which were connected to online promotion techniques for search engine manipulation commentgenerating in the scale of tens of thousands online vote manipulation mass account creation methods for covering tracks were discovered the article presents an assessment of the effectiveness of such campaigns as well as various security challenges created by these campaigns research limitations the observed campaigns form only a small portion of the overall black market this is due to inviteonly campaigns and the presence of alternative unobservable platforms practical implications the findings of this article could be input for detecting and avoiding such online campaigns social implications the findings show that in some conditions tremendous levels of manipulation of an online discourse can be achieved with a limited budget originality while there is related work on follower factories and clicktroll farms those entities offer complete solutions and their techniques are rather opaque by investigating a crowdsourcing platform this research unveils the underlying mechanics and organization of such campaigns the research is based on a uniquely large number of observations small cheap campaigns the manipulation of less significant platforms is also included while the related work tends to focus on mass politically motivated efforts
|
[['purpose', 'this', 'research', 'investigates', 'controversial', 'online', 'marketing', 'techniques', 'that', 'involve', 'buying', 'hundreds', 'or', 'even', 'thousands', 'of', 'upvotes', 'likes', 'comments', 'etc', 'methodology', 'observation', 'and', 'categorization', 'of', '7426', 'campaigns', 'posted', 'on', 'the', 'crowdsourcing', 'platform', 'microworkerscom', 'over', 'a', '365', 'day', 'ie', 'yearlong', 'period', 'were', 'conducted', 'hypotheses', 'about', 'the', 'mechanics', 'and', 'effectiveness', 'of', 'these', 'campaigns', 'were', 'established', 'and', 'evaluated', 'findings', 'the', 'campaigns', 'contained', 'a', 'combined', '1856316', 'microtasks', '897', 'of', 'which', 'were', 'connected', 'to', 'online', 'promotion', 'techniques', 'for', 'search', 'engine', 'manipulation', 'commentgenerating', 'in', 'the', 'scale', 'of', 'tens', 'of', 'thousands', 'online', 'vote', 'manipulation', 'mass', 'account', 'creation', 'methods', 'for', 'covering', 'tracks', 'were', 'discovered', 'the', 'article', 'presents', 'an', 'assessment', 'of', 'the', 'effectiveness', 'of', 'such', 'campaigns', 'as', 'well', 'as', 'various', 'security', 'challenges', 'created', 'by', 'these', 'campaigns', 'research', 'limitations', 'the', 'observed', 'campaigns', 'form', 'only', 'a', 'small', 'portion', 'of', 'the', 'overall', 'black', 'market', 'this', 'is', 'due', 'to', 'inviteonly', 'campaigns', 'and', 'the', 'presence', 'of', 'alternative', 'unobservable', 'platforms', 'practical', 'implications', 'the', 'findings', 'of', 'this', 'article', 'could', 'be', 'input', 'for', 'detecting', 'and', 'avoiding', 'such', 'online', 'campaigns', 'social', 'implications', 'the', 'findings', 'show', 'that', 'in', 'some', 'conditions', 'tremendous', 'levels', 'of', 'manipulation', 'of', 'an', 'online', 'discourse', 'can', 'be', 'achieved', 'with', 'a', 'limited', 'budget', 'originality', 'while', 'there', 'is', 'related', 'work', 'on', 'follower', 'factories', 'and', 'clicktroll', 'farms', 'those', 'entities', 'offer', 'complete', 'solutions', 'and', 'their', 'techniques', 'are', 'rather', 'opaque', 'by', 'investigating', 'a', 'crowdsourcing', 'platform', 'this', 'research', 'unveils', 'the', 'underlying', 'mechanics', 'and', 'organization', 'of', 'such', 'campaigns', 'the', 'research', 'is', 'based', 'on', 'a', 'uniquely', 'large', 'number', 'of', 'observations', 'small', 'cheap', 'campaigns', 'the', 'manipulation', 'of', 'less', 'significant', 'platforms', 'is', 'also', 'included', 'while', 'the', 'related', 'work', 'tends', 'to', 'focus', 'on', 'mass', 'politically', 'motivated', 'efforts']]
|
[-0.12723148303544696, 0.08833902544974276, -0.028171483569267186, 0.05670787690609109, -0.15481204184082648, -0.140214326385153, 0.09289363718536847, 0.39892492159178444, -0.2038320324694117, -0.38712578859801094, 0.15877699280504648, -0.3253950874960306, -0.1500306803979637, 0.2516243694249687, -0.07370365092886941, 0.035819729350909005, 0.10944548694818627, -0.0057740872671060706, 0.025794556035943255, -0.311061557223016, 0.25653461406975253, 0.0846556072872059, 0.3046459167994851, 0.09438389406137752, 0.056440866353245925, 0.01467968556189946, -0.1283996122949711, 0.0037758041940191213, -0.09868433933286225, 0.1492963143679149, 0.2931600116375907, 0.21044727716658848, 0.39506824898405696, -0.41737449366197577, -0.18494357075176987, 0.08557143489391926, 0.12341728218529811, 0.06705789704231874, -0.08770750896530409, -0.33242372200258224, 0.04858815305542164, -0.20013787406405398, -0.10846788308711029, -0.0863389526055578, 0.03156878172429096, 0.02402495729358063, -0.20781161820004676, 0.007851412339825366, 0.007884406648557999, 0.12680464824479, -0.06614908328343767, -0.10771453025586465, 0.03359501565322645, 0.18393241816529018, 0.10653873544058524, -0.020506701574606052, 0.15803779177322033, -0.1619823290236002, -0.18777029074879145, 0.4030201691641089, 0.014353340670155982, -0.10426964237053385, 0.18910772120853997, -0.0632486056326432, -0.16365239907092616, 0.09425129305032612, 0.2488375351373928, 0.13784617256354906, -0.16872234467060906, -0.0012389662575122773, -0.029585990435717736, 0.1932050802870471, 0.056300559502971526, 0.03037157389244028, 0.2508704095129289, 0.2161371260004885, 0.038839039112459506, 0.09617475962595028, -0.047747435793979665, -0.07327385410830817, -0.2250829908526594, -0.11931334671897667, -0.1490224583293585, 0.06774160191462393, -0.034215143521535485, -0.0943518804522076, 0.3799593370252599, 0.16629206380058154, 0.15649366574179308, -0.006569085383842535, 0.30191599528360014, -0.00439417411153223, 0.07759624481202314, 0.04748453138870936, 0.2176554989509111, 0.004233237673692844, 0.1569030129145283, -0.14790348531495706, 0.1279341229803714, -0.04030669307811003]
|
1,803.0703
|
Vegas: Software package for the atomistic simulation of magnetic
materials
|
We present an open-source software package, Vegas, for the atomistic
simulation of magnetic materials. Using the classical Heisenberg model and the
Monte Carlo Metropolis algorithm, Vegas provides the required tools to simulate
and analyze magnetic phenomena of a great variety of systems. Vegas stores the
history of the simulation, i.e. the magnetization and energy of the system at
every time step, allowing to analyze static and dynamic magnetic phenomena from
results obtained in a single simulation. Also, standardized input and output
file formats are employed to facilitate the simulation process and the exchange
and archiving of data. We include results from simulations performed using
Vegas, showing its applicability to study different magnetic phenomena.
|
physics.comp-ph
|
we present an opensource software package vegas for the atomistic simulation of magnetic materials using the classical heisenberg model and the monte carlo metropolis algorithm vegas provides the required tools to simulate and analyze magnetic phenomena of a great variety of systems vegas stores the history of the simulation ie the magnetization and energy of the system at every time step allowing to analyze static and dynamic magnetic phenomena from results obtained in a single simulation also standardized input and output file formats are employed to facilitate the simulation process and the exchange and archiving of data we include results from simulations performed using vegas showing its applicability to study different magnetic phenomena
|
[['we', 'present', 'an', 'opensource', 'software', 'package', 'vegas', 'for', 'the', 'atomistic', 'simulation', 'of', 'magnetic', 'materials', 'using', 'the', 'classical', 'heisenberg', 'model', 'and', 'the', 'monte', 'carlo', 'metropolis', 'algorithm', 'vegas', 'provides', 'the', 'required', 'tools', 'to', 'simulate', 'and', 'analyze', 'magnetic', 'phenomena', 'of', 'a', 'great', 'variety', 'of', 'systems', 'vegas', 'stores', 'the', 'history', 'of', 'the', 'simulation', 'ie', 'the', 'magnetization', 'and', 'energy', 'of', 'the', 'system', 'at', 'every', 'time', 'step', 'allowing', 'to', 'analyze', 'static', 'and', 'dynamic', 'magnetic', 'phenomena', 'from', 'results', 'obtained', 'in', 'a', 'single', 'simulation', 'also', 'standardized', 'input', 'and', 'output', 'file', 'formats', 'are', 'employed', 'to', 'facilitate', 'the', 'simulation', 'process', 'and', 'the', 'exchange', 'and', 'archiving', 'of', 'data', 'we', 'include', 'results', 'from', 'simulations', 'performed', 'using', 'vegas', 'showing', 'its', 'applicability', 'to', 'study', 'different', 'magnetic', 'phenomena']]
|
[-0.10516860018756273, 0.03425083654446927, -0.10519935279689004, 0.09102441410313422, -0.04062320594263749, -0.10360698155910436, 0.05385372309896073, 0.39845248507912706, -0.29776846357843784, -0.3761251322034977, 0.0902427015990942, -0.2515918255157241, -0.10798369978546304, 0.2813981239646838, 0.05126842666948956, 0.0819665322371808, 0.12315789646823454, -0.034860956132313055, -0.051554966510883406, -0.22547817595954162, 0.23229712475115943, 0.1257418264362928, 0.2746994566127032, 0.02693952158076969, 0.11247612522045497, 0.06161521044271314, -0.037463757753438125, 0.0163333751590906, -0.17818635955156215, 0.05790334027178124, 0.22426746788525345, 0.13784170637434695, 0.22859198250189688, -0.48774312112137336, -0.16734856649804697, 0.06076380237524884, 0.1300421336138275, 0.14786670315779943, -0.08535212148969944, -0.27991783165628403, 0.06805998735970496, -0.18476948936560514, -0.10825675310550538, -0.11645700180474504, -0.0804172476930791, 0.05385956601486994, -0.29649818335882333, 0.021727329900692243, -0.01463062357259461, 0.11513405513282107, -0.059777614789339094, -0.08983341053816432, -0.02179151473039415, 0.16161694435456322, -0.016511147349364066, 0.027656051262273593, 0.1341153035322575, -0.08569430450669828, -0.19378491336133627, 0.3838928347387541, -0.011192558941109914, -0.12636048171207703, 0.19966429133231925, -0.10547246783971786, -0.1311387449865584, 0.13630806816436877, 0.211846192243748, 0.08898438681411532, -0.17856640441227803, 0.10261878162772864, 0.0169360728942649, 0.1668423245850522, -0.06257280274253108, -0.0016912885537717194, 0.1507825973233521, 0.20658680541951835, -0.03781350905207538, 0.1934163449290909, -0.10303918669691549, -0.15940824035087403, -0.23950881380752653, -0.1729693950248668, -0.18040506710685725, -0.0037127256793159564, -0.105629445712079, -0.17793934577169407, 0.40492181415644896, 0.24852839885928577, 0.09413706343126509, 0.04412570089901245, 0.33915416494143746, 0.02795456334190295, 0.05023458376073534, 0.10746028578419865, 0.1333061499929105, 0.09472789904267519, 0.2030445279932655, -0.21784424863805155, 0.06507894982670359, 0.020950053760831335]
|
1,803.07031
|
Factorised spatial representation learning: application in
semi-supervised myocardial segmentation
|
The success and generalisation of deep learning algorithms heavily depend on
learning good feature representations. In medical imaging this entails
representing anatomical information, as well as properties related to the
specific imaging setting. Anatomical information is required to perform further
analysis, whereas imaging information is key to disentangle scanner variability
and potential artefacts. The ability to factorise these would allow for
training algorithms only on the relevant information according to the task. To
date, such factorisation has not been attempted. In this paper, we propose a
methodology of latent space factorisation relying on the cycle-consistency
principle. As an example application, we consider cardiac MR segmentation,
where we separate information related to the myocardium from other features
related to imaging and surrounding substructures. We demonstrate the proposed
method's utility in a semi-supervised setting: we use very few labelled images
together with many unlabelled images to train a myocardium segmentation neural
network. Specifically, we achieve comparable performance to fully supervised
networks using a fraction of labelled images in experiments on ACDC and a
dataset from Edinburgh Imaging Facility QMRI. Code will be made available at
https://github.com/agis85/spatial_factorisation.
|
cs.CV
|
the success and generalisation of deep learning algorithms heavily depend on learning good feature representations in medical imaging this entails representing anatomical information as well as properties related to the specific imaging setting anatomical information is required to perform further analysis whereas imaging information is key to disentangle scanner variability and potential artefacts the ability to factorise these would allow for training algorithms only on the relevant information according to the task to date such factorisation has not been attempted in this paper we propose a methodology of latent space factorisation relying on the cycleconsistency principle as an example application we consider cardiac mr segmentation where we separate information related to the myocardium from other features related to imaging and surrounding substructures we demonstrate the proposed methods utility in a semisupervised setting we use very few labelled images together with many unlabelled images to train a myocardium segmentation neural network specifically we achieve comparable performance to fully supervised networks using a fraction of labelled images in experiments on acdc and a dataset from edinburgh imaging facility qmri code will be made available at httpsgithubcomagis85spatial_factorisation
|
[['the', 'success', 'and', 'generalisation', 'of', 'deep', 'learning', 'algorithms', 'heavily', 'depend', 'on', 'learning', 'good', 'feature', 'representations', 'in', 'medical', 'imaging', 'this', 'entails', 'representing', 'anatomical', 'information', 'as', 'well', 'as', 'properties', 'related', 'to', 'the', 'specific', 'imaging', 'setting', 'anatomical', 'information', 'is', 'required', 'to', 'perform', 'further', 'analysis', 'whereas', 'imaging', 'information', 'is', 'key', 'to', 'disentangle', 'scanner', 'variability', 'and', 'potential', 'artefacts', 'the', 'ability', 'to', 'factorise', 'these', 'would', 'allow', 'for', 'training', 'algorithms', 'only', 'on', 'the', 'relevant', 'information', 'according', 'to', 'the', 'task', 'to', 'date', 'such', 'factorisation', 'has', 'not', 'been', 'attempted', 'in', 'this', 'paper', 'we', 'propose', 'a', 'methodology', 'of', 'latent', 'space', 'factorisation', 'relying', 'on', 'the', 'cycleconsistency', 'principle', 'as', 'an', 'example', 'application', 'we', 'consider', 'cardiac', 'mr', 'segmentation', 'where', 'we', 'separate', 'information', 'related', 'to', 'the', 'myocardium', 'from', 'other', 'features', 'related', 'to', 'imaging', 'and', 'surrounding', 'substructures', 'we', 'demonstrate', 'the', 'proposed', 'methods', 'utility', 'in', 'a', 'semisupervised', 'setting', 'we', 'use', 'very', 'few', 'labelled', 'images', 'together', 'with', 'many', 'unlabelled', 'images', 'to', 'train', 'a', 'myocardium', 'segmentation', 'neural', 'network', 'specifically', 'we', 'achieve', 'comparable', 'performance', 'to', 'fully', 'supervised', 'networks', 'using', 'a', 'fraction', 'of', 'labelled', 'images', 'in', 'experiments', 'on', 'acdc', 'and', 'a', 'dataset', 'from', 'edinburgh', 'imaging', 'facility', 'qmri', 'code', 'will', 'be', 'made', 'available', 'at', 'httpsgithubcomagis85spatial_factorisation']]
|
[0.006560047963746095, -0.01913553092536794, -0.062076752292898184, 0.0819568359013138, -0.15990496483056352, -0.1502038055262401, 0.018223613043203746, 0.4572576952314442, -0.2701198325996272, -0.34697196033116573, 0.12805048495854246, -0.2894216984602027, -0.17413683144898598, 0.20204524935065396, -0.15354465391700628, 0.08090022838893321, 0.13472857929847606, 0.06582979651936458, -0.028510493179274305, -0.23859655529723753, 0.2950207281175777, 0.052477827721721965, 0.33582804556121754, 0.036420760238594044, 0.14209543171343827, -0.0031826209612165275, -0.055538957584852895, 0.009738763207892564, -0.08786147039210618, 0.1614075649740897, 0.3541532785166055, 0.20350899554336127, 0.2979209716907119, -0.41529103786725285, -0.21564856950063868, 0.10689161104898227, 0.15820727872921794, 0.1071121967702982, -0.021329506309295858, -0.33210123578071227, 0.052957045658659496, -0.12015148984329378, 0.011046215709899374, -0.16589083099646157, -0.07209338506370722, -0.03331986775041604, -0.28164957562217213, 0.04812515197102937, 0.02138909539576783, 0.08611853319459437, -0.07773750572773257, -0.08449900804515012, 0.030050897811758306, 0.1840676509220499, 0.006597705673339873, 0.06619682699083121, 0.14007889519603364, -0.20276452511386142, -0.1214707469156704, 0.3398722677486516, -0.026379935318716075, -0.19883923078480029, 0.23207020601563033, -0.07256990234377728, -0.18909294655943504, 0.1162508053252158, 0.24294780194250448, 0.11927805722390857, -0.17546119821853326, -0.007903721034679501, -0.024619932138218538, 0.2035100011102845, 0.056490224057075676, 0.024536349492585235, 0.17014956096177056, 0.24540163288554534, -0.007296494371448567, 0.15245501026784736, -0.18482201488922692, -0.02777030746467778, -0.2141692898047915, -0.10914247493193449, -0.19841273818444968, 0.008998103973616672, -0.05665407443000513, -0.14760325429006863, 0.3814805973438251, 0.2471419996264692, 0.2111836908476763, 0.04028624012592997, 0.3391684063460902, -0.015194688354939466, 0.16350928058369402, 0.03248150755054587, 0.17130249178372933, 0.07498695292433993, 0.12937353323709952, -0.16183110246119278, 0.07368072145236809, 0.043908642797064176]
|
1,803.07032
|
Embedding graphs into two-dimensional simplicial complexes
|
We consider the problem of deciding whether an input graph G admits a
topological embedding into a two-dimensional simplicial complex C. This problem
includes, among others, the embeddability problem of a graph on a surface and
the topological crossing number of a graph, but is more general.
The problem is NP-complete when C is part of the input, and we give a
polynomial-time algorithm if the complex C is fixed.
Our strategy is to reduce the problem to an embedding extension problem on a
surface, which has the following form: Given a subgraph H' of a graph G', and
an embedding of H' on a surface S, can that embedding be extended to an
embedding of G' on S? Such problems can be solved, in turn, using a key
component in Mohar's algorithm to decide the embeddability of a graph on a
fixed surface (STOC 1996, SIAM J. Discr. Math. 1999).
|
cs.CG
|
we consider the problem of deciding whether an input graph g admits a topological embedding into a twodimensional simplicial complex c this problem includes among others the embeddability problem of a graph on a surface and the topological crossing number of a graph but is more general the problem is npcomplete when c is part of the input and we give a polynomialtime algorithm if the complex c is fixed our strategy is to reduce the problem to an embedding extension problem on a surface which has the following form given a subgraph h of a graph g and an embedding of h on a surface s can that embedding be extended to an embedding of g on s such problems can be solved in turn using a key component in mohars algorithm to decide the embeddability of a graph on a fixed surface stoc 1996 siam j discr math 1999
|
[['we', 'consider', 'the', 'problem', 'of', 'deciding', 'whether', 'an', 'input', 'graph', 'g', 'admits', 'a', 'topological', 'embedding', 'into', 'a', 'twodimensional', 'simplicial', 'complex', 'c', 'this', 'problem', 'includes', 'among', 'others', 'the', 'embeddability', 'problem', 'of', 'a', 'graph', 'on', 'a', 'surface', 'and', 'the', 'topological', 'crossing', 'number', 'of', 'a', 'graph', 'but', 'is', 'more', 'general', 'the', 'problem', 'is', 'npcomplete', 'when', 'c', 'is', 'part', 'of', 'the', 'input', 'and', 'we', 'give', 'a', 'polynomialtime', 'algorithm', 'if', 'the', 'complex', 'c', 'is', 'fixed', 'our', 'strategy', 'is', 'to', 'reduce', 'the', 'problem', 'to', 'an', 'embedding', 'extension', 'problem', 'on', 'a', 'surface', 'which', 'has', 'the', 'following', 'form', 'given', 'a', 'subgraph', 'h', 'of', 'a', 'graph', 'g', 'and', 'an', 'embedding', 'of', 'h', 'on', 'a', 'surface', 's', 'can', 'that', 'embedding', 'be', 'extended', 'to', 'an', 'embedding', 'of', 'g', 'on', 's', 'such', 'problems', 'can', 'be', 'solved', 'in', 'turn', 'using', 'a', 'key', 'component', 'in', 'mohars', 'algorithm', 'to', 'decide', 'the', 'embeddability', 'of', 'a', 'graph', 'on', 'a', 'fixed', 'surface', 'stoc', '1996', 'siam', 'j', 'discr', 'math', '1999']]
|
[-0.13266404362473017, 0.04232978991737279, -0.08765080223791301, 0.02789192647052308, -0.13213172130597134, -0.14151464072056114, 0.058191843442618844, 0.3743251065909863, -0.32622652939210334, -0.3300739939138293, 0.09778009069850668, -0.26511592397931966, -0.16164602216333152, 0.16327840295930704, -0.12741756867772588, -0.0020070751508076985, 0.0888177379577731, 0.06108500888571143, -0.010226439796388148, -0.27296252288254136, 0.31648821825161577, -0.0327920586677889, 0.18486342609801795, 0.08346473752210537, 0.09442707909426341, 0.03717404907569289, 0.008053049643834432, 0.08819940678154428, -0.14202939910062318, 0.11589699996790538, 0.25574774748800944, 0.16235776601669688, 0.28084674873078863, -0.36617211708799, -0.20745041019283236, 0.18498218142970776, 0.09252359819598496, 0.07228935052563126, 0.010484669081536897, -0.254052677291135, 0.11646292338031344, -0.09272073689848184, -0.0299474157517155, 0.015208267414321502, 0.1269324995453159, -0.08314013103023171, -0.2943607555702329, -0.039784320819502075, 0.13463063277304171, 0.023879474997520446, 0.003189272090482215, -0.08807358411994452, -0.04081204365783681, 0.07886303427260524, -0.07492943882864589, 0.14330400951206684, 0.04490251261430482, -0.1132495747304832, -0.13448669190829, 0.4198460434873899, -0.03430856416312357, -0.21405773676310977, 0.1458463819200794, -0.020380658054103454, -0.16365413868178924, 0.12404630899429321, 0.18156177054935446, 0.14995289550162852, -0.07799306166562019, 0.20624006435779543, -0.14640977847700318, 0.1640633193589747, 0.07138238504528999, -0.07459755735277819, 0.13545273353966575, 0.1772171951768299, 0.17258175188985964, 0.1743342751621579, -0.001536075440235436, 0.028652858485778174, -0.27534873655376335, -0.18213786457277215, -0.2217635245559116, 0.07434424256905914, -0.11503575234023931, -0.19652026001984874, 0.42998322504727793, 0.06635615551844239, 0.20977929371176288, 0.03800104657071643, 0.2201668885257095, 0.11694454012205824, -0.010705621066348007, 0.1656215525108079, 0.10573417294460039, 0.1713573910171787, -0.007462065756941835, -0.1887818049484243, 0.0442881462102135, 0.1677397721198698]
|
1,803.07033
|
Natural gradient via optimal transport
|
We study a natural Wasserstein gradient flow on manifolds of probability
distributions with discrete sample spaces. We derive the Riemannian structure
for the probability simplex from the dynamical formulation of the Wasserstein
distance on a weighted graph. We pull back the geometric structure to the
parameter space of any given probability model, which allows us to define a
natural gradient flow there. In contrast to the natural Fisher-Rao gradient,
the natural Wasserstein gradient incorporates a ground metric on sample space.
We illustrate the analysis of elementary exponential family examples and
demonstrate an application of the Wasserstein natural gradient to maximum
likelihood estimation.
|
math.OC cs.IT math.IT
|
we study a natural wasserstein gradient flow on manifolds of probability distributions with discrete sample spaces we derive the riemannian structure for the probability simplex from the dynamical formulation of the wasserstein distance on a weighted graph we pull back the geometric structure to the parameter space of any given probability model which allows us to define a natural gradient flow there in contrast to the natural fisherrao gradient the natural wasserstein gradient incorporates a ground metric on sample space we illustrate the analysis of elementary exponential family examples and demonstrate an application of the wasserstein natural gradient to maximum likelihood estimation
|
[['we', 'study', 'a', 'natural', 'wasserstein', 'gradient', 'flow', 'on', 'manifolds', 'of', 'probability', 'distributions', 'with', 'discrete', 'sample', 'spaces', 'we', 'derive', 'the', 'riemannian', 'structure', 'for', 'the', 'probability', 'simplex', 'from', 'the', 'dynamical', 'formulation', 'of', 'the', 'wasserstein', 'distance', 'on', 'a', 'weighted', 'graph', 'we', 'pull', 'back', 'the', 'geometric', 'structure', 'to', 'the', 'parameter', 'space', 'of', 'any', 'given', 'probability', 'model', 'which', 'allows', 'us', 'to', 'define', 'a', 'natural', 'gradient', 'flow', 'there', 'in', 'contrast', 'to', 'the', 'natural', 'fisherrao', 'gradient', 'the', 'natural', 'wasserstein', 'gradient', 'incorporates', 'a', 'ground', 'metric', 'on', 'sample', 'space', 'we', 'illustrate', 'the', 'analysis', 'of', 'elementary', 'exponential', 'family', 'examples', 'and', 'demonstrate', 'an', 'application', 'of', 'the', 'wasserstein', 'natural', 'gradient', 'to', 'maximum', 'likelihood', 'estimation']]
|
[-0.07368835938783984, 0.022090232941492087, -0.1381765255868873, 0.13672779438282162, -0.118568455471712, -0.054893720836844295, 0.049599262264867626, 0.3885392215760315, -0.3576586160365967, -0.2702680524237746, 0.05024977929903852, -0.2631435874399019, -0.16664562096839824, 0.1540101026960959, -0.16705337240744164, 0.09852254121819985, 0.05942680213746487, 0.07961634599932414, -0.12785954129261276, -0.19823388834443975, 0.38014545228660984, 0.03558147577660195, 0.3007869872027168, -0.008569938663676308, 0.2084857722032158, -0.004806037508316484, -0.004478897607209636, 0.04175620188642129, -0.19612402158478895, 0.18692241893743403, 0.16147589833731307, 0.15458125396923839, 0.29544179365221485, -0.3714922529583347, -0.25196802627989184, 0.17723255526895323, 0.06504272725592897, 0.0788537541657741, -0.03446540185227515, -0.29571536860848757, 0.036248110645615006, -0.11107166157122336, -0.08674539165005234, -0.0948909789565768, -0.008305477590172314, 0.014925525612745653, -0.29796960872858214, 0.02860917279259393, 0.06860243557700112, 0.0462739304593746, -0.06709915439783157, -0.10795280673340255, -0.019215050984320102, 0.08467378026312765, 0.043573525459186045, 0.08879647898606445, 0.1296136027393753, -0.035118722986868196, -0.08795106358479197, 0.3373468796118829, -0.12355935711792543, -0.2640568687598787, 0.15592211139315337, -0.11525032802612759, -0.1179135119058557, 0.05373851668235718, 0.26276333059421647, 0.17764624982487923, -0.10771339701821882, 0.11480885014045235, -0.04310560235571043, 0.09363311032454173, 0.03911352472598938, -0.007812632375634183, 0.10446761629096799, 0.13990930380646652, 0.22340876909484172, 0.1675461755115904, -0.11173928389211606, -0.20494277808329037, -0.31717803329229355, -0.21226809155561177, -0.20796252586239694, 0.06637862028768651, -0.2162466079209801, -0.20414899001080616, 0.3784816773224841, 0.09015579696279019, 0.2623671539967843, 0.14665856792970433, 0.2613733530880007, 0.09410749634673052, 0.0028408805967545976, 0.10760223586818457, 0.16233736080318398, 0.18305740459347328, 0.033415942544154094, -0.1859921057064853, 0.0625054881036026, 0.14976307135486208]
|
1,803.07034
|
Analysis of the baryonic state $|[qc]c\rangle$
|
In this note we analyse the structure of the baryonic state $|[qc]c\rangle$
with a spin-0 diquark $[qc]$, as compared to baryonic states $|(qc)c\rangle$
and $|q(cc)\rangle$ containing internal spin-1 diquark states. While one can
identify the state $|q(cc)\rangle$ with the state observed at LHCb, the state
$|(qc)c\rangle$ could probably be part of the state $\Xi_{cc}^{++}(3780)$.
Accordingly, the ground state of $|[qc]c\rangle$ can be identified with the
state $\Xi_{cc}^+(3520)$.
|
hep-ph
|
in this note we analyse the structure of the baryonic state qccrangle with a spin0 diquark qc as compared to baryonic states qccrangle and qccrangle containing internal spin1 diquark states while one can identify the state qccrangle with the state observed at lhcb the state qccrangle could probably be part of the state xi_cc3780 accordingly the ground state of qccrangle can be identified with the state xi_cc3520
|
[['in', 'this', 'note', 'we', 'analyse', 'the', 'structure', 'of', 'the', 'baryonic', 'state', 'qccrangle', 'with', 'a', 'spin0', 'diquark', 'qc', 'as', 'compared', 'to', 'baryonic', 'states', 'qccrangle', 'and', 'qccrangle', 'containing', 'internal', 'spin1', 'diquark', 'states', 'while', 'one', 'can', 'identify', 'the', 'state', 'qccrangle', 'with', 'the', 'state', 'observed', 'at', 'lhcb', 'the', 'state', 'qccrangle', 'could', 'probably', 'be', 'part', 'of', 'the', 'state', 'xi_cc3780', 'accordingly', 'the', 'ground', 'state', 'of', 'qccrangle', 'can', 'be', 'identified', 'with', 'the', 'state', 'xi_cc3520']]
|
[-0.0919036694774122, 0.25157986069098115, -0.09364622740328989, 0.07260684391561274, -0.03951204829552973, -0.10933177869512954, 0.04939015494715987, 0.2844634268884406, -0.20194086265947783, -0.2922236154589689, 0.055700852900785816, -0.3040202022389029, 0.025108669912724785, 0.036435422797997795, 0.07443693199787628, 0.03084687270562757, 0.07986500801229285, 0.11812227675832357, -0.05417166981902538, -0.20674848098265516, 0.36855075282580924, -0.02106107161803679, 0.20677417882887478, 0.027334394130968685, 0.04019156985327065, -0.07884664212840355, 0.09508818743581121, -0.030130194270785785, -0.06629531683089833, 0.029186094573092167, 0.25339928695536923, 0.11552365863639297, 0.1434371529295194, -0.38119400806273473, -0.15416732064984512, 0.13280358268865244, 0.15885497370001042, 0.2056337425407643, 0.01046009288366997, -0.4296511525683331, 0.06540641382647057, -0.2212211514054092, -0.1743473635817116, -0.11909515050832521, -0.05656944589237824, -0.08897520074088154, -0.209125695070146, 0.14210087426401902, -0.03075914210851558, -0.04875221502769626, -0.10954642090875881, -0.22898811783119472, -0.1191891171143983, 0.047460488403554664, 0.0008013147409215118, 0.10979897541233874, 0.10489384404552932, -0.20500481275093713, -0.14252518190804755, 0.3394527060092624, -0.07088515585090852, -0.16772332368418574, 0.1753194244493815, -0.13079215460598018, -0.07665096363052726, 0.08409328149123625, 0.1475454662630165, 0.01937395121168458, -0.12397290351465486, 0.026151577306198746, -0.031889056293011614, 0.22626272261594282, 0.01483478881136486, 0.1285960447664062, 0.24098757343987623, 0.1548014976733336, -0.010493361934398612, 0.18626735884004808, -0.08412654318310546, -0.12037377019949032, -0.30787530322700285, -0.1600355840725542, -0.14958422704402244, 0.05925650043046159, 0.050363097156646705, -0.09861860592905997, 0.4183770172072179, 0.03456642065253673, 0.2408026662006071, -0.05935217619690141, 0.23717554125257514, 0.061613836309830236, 0.035655166149478064, 0.1200215885553255, 0.30531582620107767, 0.16617063858376985, 0.08188378454228355, -0.30543438730422745, 0.0772026107067976, -0.0010778362241884072]
|
1,803.07035
|
Prandtl-Number Effects in High-Rayleigh-Number Spherical Convection
|
Convection is the predominant mechanism by which energy and angular momentum
are transported in the outer portion of the Sun. The resulting overturning
motions are also the primary energy source for the solar magnetic field. An
accurate solar dynamo model therefore requires a complete description of the
convective motions, but these motions remain poorly understood. Studying
stellar convection numerically remains challenging; it occurs within a
parameter regime that is extreme by computational standards. The fluid
properties of the convection zone are characterized in part by the Prandtl
number $\mathrm{Pr}=\nu/\kappa$, where $\nu$ is the kinematic viscosity and
$\kappa$ is the thermal diffusion; in stars, $\mathrm{Pr}$ is extremely low,
$\mathrm{Pr}\approx 10^{-7}$. The influence of $\mathrm{Pr}$ on the convective
motions at the heart of the dynamo is not well understood since most numerical
studies are limited to using $\mathrm{Pr}\approx1$. We systematically vary
$\mathrm{Pr}$ and the degree of thermal forcing, characterized through a
Rayleigh number, to explore its influence on the convective dynamics. For
sufficiently large thermal driving, the simulations reach a so-called
convective free-fall state where diffusion no longer plays an important role in
the interior dynamics. Simulations with a lower $\mathrm{Pr}$ generate faster
convective flows and broader ranges of scales for equivalent levels of thermal
forcing. Characteristics of the spectral distribution of the velocity remain
largely insensitive to changes in $\mathrm{Pr}$. Importantly, we find that
$\mathrm{Pr}$ plays a key role in determining when the free-fall regime is
reached by controlling the thickness of the thermal boundary layer.
|
astro-ph.SR physics.flu-dyn
|
convection is the predominant mechanism by which energy and angular momentum are transported in the outer portion of the sun the resulting overturning motions are also the primary energy source for the solar magnetic field an accurate solar dynamo model therefore requires a complete description of the convective motions but these motions remain poorly understood studying stellar convection numerically remains challenging it occurs within a parameter regime that is extreme by computational standards the fluid properties of the convection zone are characterized in part by the prandtl number mathrmprnukappa where nu is the kinematic viscosity and kappa is the thermal diffusion in stars mathrmpr is extremely low mathrmprapprox 107 the influence of mathrmpr on the convective motions at the heart of the dynamo is not well understood since most numerical studies are limited to using mathrmprapprox1 we systematically vary mathrmpr and the degree of thermal forcing characterized through a rayleigh number to explore its influence on the convective dynamics for sufficiently large thermal driving the simulations reach a socalled convective freefall state where diffusion no longer plays an important role in the interior dynamics simulations with a lower mathrmpr generate faster convective flows and broader ranges of scales for equivalent levels of thermal forcing characteristics of the spectral distribution of the velocity remain largely insensitive to changes in mathrmpr importantly we find that mathrmpr plays a key role in determining when the freefall regime is reached by controlling the thickness of the thermal boundary layer
|
[['convection', 'is', 'the', 'predominant', 'mechanism', 'by', 'which', 'energy', 'and', 'angular', 'momentum', 'are', 'transported', 'in', 'the', 'outer', 'portion', 'of', 'the', 'sun', 'the', 'resulting', 'overturning', 'motions', 'are', 'also', 'the', 'primary', 'energy', 'source', 'for', 'the', 'solar', 'magnetic', 'field', 'an', 'accurate', 'solar', 'dynamo', 'model', 'therefore', 'requires', 'a', 'complete', 'description', 'of', 'the', 'convective', 'motions', 'but', 'these', 'motions', 'remain', 'poorly', 'understood', 'studying', 'stellar', 'convection', 'numerically', 'remains', 'challenging', 'it', 'occurs', 'within', 'a', 'parameter', 'regime', 'that', 'is', 'extreme', 'by', 'computational', 'standards', 'the', 'fluid', 'properties', 'of', 'the', 'convection', 'zone', 'are', 'characterized', 'in', 'part', 'by', 'the', 'prandtl', 'number', 'mathrmprnukappa', 'where', 'nu', 'is', 'the', 'kinematic', 'viscosity', 'and', 'kappa', 'is', 'the', 'thermal', 'diffusion', 'in', 'stars', 'mathrmpr', 'is', 'extremely', 'low', 'mathrmprapprox', '107', 'the', 'influence', 'of', 'mathrmpr', 'on', 'the', 'convective', 'motions', 'at', 'the', 'heart', 'of', 'the', 'dynamo', 'is', 'not', 'well', 'understood', 'since', 'most', 'numerical', 'studies', 'are', 'limited', 'to', 'using', 'mathrmprapprox1', 'we', 'systematically', 'vary', 'mathrmpr', 'and', 'the', 'degree', 'of', 'thermal', 'forcing', 'characterized', 'through', 'a', 'rayleigh', 'number', 'to', 'explore', 'its', 'influence', 'on', 'the', 'convective', 'dynamics', 'for', 'sufficiently', 'large', 'thermal', 'driving', 'the', 'simulations', 'reach', 'a', 'socalled', 'convective', 'freefall', 'state', 'where', 'diffusion', 'no', 'longer', 'plays', 'an', 'important', 'role', 'in', 'the', 'interior', 'dynamics', 'simulations', 'with', 'a', 'lower', 'mathrmpr', 'generate', 'faster', 'convective', 'flows', 'and', 'broader', 'ranges', 'of', 'scales', 'for', 'equivalent', 'levels', 'of', 'thermal', 'forcing', 'characteristics', 'of', 'the', 'spectral', 'distribution', 'of', 'the', 'velocity', 'remain', 'largely', 'insensitive', 'to', 'changes', 'in', 'mathrmpr', 'importantly', 'we', 'find', 'that', 'mathrmpr', 'plays', 'a', 'key', 'role', 'in', 'determining', 'when', 'the', 'freefall', 'regime', 'is', 'reached', 'by', 'controlling', 'the', 'thickness', 'of', 'the', 'thermal', 'boundary', 'layer']]
|
[-0.16379944038912192, 0.2449552473461319, -0.03513772129678901, 0.06955744894481194, -0.049097615722297455, -0.039474737014590706, 0.02880036342438803, 0.3175991811474, -0.27147455495822603, -0.3262452914991439, 0.0982856521890922, -0.19895787701041492, -0.06345855896091782, 0.22525253670948195, -0.03997132686363179, -0.005870010736273325, 0.06685507881190483, -0.0009490322891222544, 0.0182237409378502, -0.1587681047337453, 0.2985230827278819, 0.11023807053142497, 0.2305489947667253, 0.03765652792574934, 0.06503377813140646, -0.12111281035737373, -0.025494015787166258, 0.028120808054169655, -0.1704464042485304, 0.02678421841651583, 0.21074539778873416, 0.010550140305075888, 0.2876207750963628, -0.4407929160684147, -0.26532994950101674, 0.03634676932788277, 0.1834147372321526, 0.0714018600526235, -0.009629436375088373, -0.1816366115808179, 0.06842099854814981, -0.11802036730214917, -0.13985668894765543, -0.03954109647272786, 0.0722521102245443, 0.0008839797647092646, -0.2708153949380845, 0.15877625395383682, 0.06532907476869973, 0.10943739817377703, -0.08768429987426955, -0.09625044385979552, -0.09554416639634124, 0.14682686932383524, 0.07497086503287038, 0.014497955124786755, 0.192406297940376, -0.20054318585066502, 0.027885408656409948, 0.41395286786416163, -0.06894721831907018, -0.18627775048890943, 0.20276005033495997, -0.1945821981249793, -0.07461350783320868, 0.18478824335827745, 0.14446090037471707, 0.14132689017887143, -0.10336466051941431, 0.03939576042550982, -0.02577794387586384, 0.1551259155077321, 0.050985817409751645, 0.027449627825413055, 0.2467394408792515, 0.2301489828454623, 0.05905014170576195, 0.08076265981336209, -0.16501468612162074, -0.1304162786013162, -0.2609297798634776, -0.09727496912933584, -0.15484150190364324, 0.040224534003432046, -0.09647228751376787, -0.1743319490627426, 0.3512787167978673, 0.16490635177086171, 0.16742124336132827, 0.0013633324684813803, 0.30282492197863375, 0.13712622678919487, 0.05373805266620268, 0.15682966692646397, 0.3196759160092362, 0.18842534010186945, 0.13160249768864085, -0.3015985926988435, 0.10920900763503145, 0.036415086354875614]
|
1,803.07036
|
Characterizing the Epoch of Reionization with the small-scale CMB:
constraints on the optical depth and physical parameters
|
Patchy reionization leaves a number of imprints on the small-scale cosmic
microwave background (CMB) temperature fluctuations, the largest of which is
the kinematic Sunyaev-Zel'dovich (kSZ), the Doppler shift of CMB photons
scattering off moving electrons in ionized bubbles. It has long been known that
in the CMB power spectrum, this imprint of reionization is largely degenerate
with the kSZ signal produced by late-time galaxies and clusters, thus limiting
our ability to constrain reionization. Following Smith & Ferraro (2017), it is
possible to isolate the reionization contribution in a model independent way,
by looking at the large scale modulation of the small scale CMB power spectrum.
In this paper we extend the formalism to use the full shape information of the
small scale power spectrum (rather than just its broadband average), and argue
that this is necessary to break the degeneracy between the optical depth $\tau$
and parameters setting the duration of reionization. In particular, we show
that the next generation of CMB experiments could achieve up to a factor of 3
improvement on the optical depth $\tau$ and at the same time, constrain the
duration of reionization to $\sim$ 25 %. This can help tighten the constrains
on neutrino masses, which will be limited by our knowledge of $\tau$, and shed
light on the physical processes responsible for reionization.
|
astro-ph.CO
|
patchy reionization leaves a number of imprints on the smallscale cosmic microwave background cmb temperature fluctuations the largest of which is the kinematic sunyaevzeldovich ksz the doppler shift of cmb photons scattering off moving electrons in ionized bubbles it has long been known that in the cmb power spectrum this imprint of reionization is largely degenerate with the ksz signal produced by latetime galaxies and clusters thus limiting our ability to constrain reionization following smith ferraro 2017 it is possible to isolate the reionization contribution in a model independent way by looking at the large scale modulation of the small scale cmb power spectrum in this paper we extend the formalism to use the full shape information of the small scale power spectrum rather than just its broadband average and argue that this is necessary to break the degeneracy between the optical depth tau and parameters setting the duration of reionization in particular we show that the next generation of cmb experiments could achieve up to a factor of 3 improvement on the optical depth tau and at the same time constrain the duration of reionization to sim 25 this can help tighten the constrains on neutrino masses which will be limited by our knowledge of tau and shed light on the physical processes responsible for reionization
|
[['patchy', 'reionization', 'leaves', 'a', 'number', 'of', 'imprints', 'on', 'the', 'smallscale', 'cosmic', 'microwave', 'background', 'cmb', 'temperature', 'fluctuations', 'the', 'largest', 'of', 'which', 'is', 'the', 'kinematic', 'sunyaevzeldovich', 'ksz', 'the', 'doppler', 'shift', 'of', 'cmb', 'photons', 'scattering', 'off', 'moving', 'electrons', 'in', 'ionized', 'bubbles', 'it', 'has', 'long', 'been', 'known', 'that', 'in', 'the', 'cmb', 'power', 'spectrum', 'this', 'imprint', 'of', 'reionization', 'is', 'largely', 'degenerate', 'with', 'the', 'ksz', 'signal', 'produced', 'by', 'latetime', 'galaxies', 'and', 'clusters', 'thus', 'limiting', 'our', 'ability', 'to', 'constrain', 'reionization', 'following', 'smith', 'ferraro', '2017', 'it', 'is', 'possible', 'to', 'isolate', 'the', 'reionization', 'contribution', 'in', 'a', 'model', 'independent', 'way', 'by', 'looking', 'at', 'the', 'large', 'scale', 'modulation', 'of', 'the', 'small', 'scale', 'cmb', 'power', 'spectrum', 'in', 'this', 'paper', 'we', 'extend', 'the', 'formalism', 'to', 'use', 'the', 'full', 'shape', 'information', 'of', 'the', 'small', 'scale', 'power', 'spectrum', 'rather', 'than', 'just', 'its', 'broadband', 'average', 'and', 'argue', 'that', 'this', 'is', 'necessary', 'to', 'break', 'the', 'degeneracy', 'between', 'the', 'optical', 'depth', 'tau', 'and', 'parameters', 'setting', 'the', 'duration', 'of', 'reionization', 'in', 'particular', 'we', 'show', 'that', 'the', 'next', 'generation', 'of', 'cmb', 'experiments', 'could', 'achieve', 'up', 'to', 'a', 'factor', 'of', '3', 'improvement', 'on', 'the', 'optical', 'depth', 'tau', 'and', 'at', 'the', 'same', 'time', 'constrain', 'the', 'duration', 'of', 'reionization', 'to', 'sim', '25', 'this', 'can', 'help', 'tighten', 'the', 'constrains', 'on', 'neutrino', 'masses', 'which', 'will', 'be', 'limited', 'by', 'our', 'knowledge', 'of', 'tau', 'and', 'shed', 'light', 'on', 'the', 'physical', 'processes', 'responsible', 'for', 'reionization']]
|
[-0.0741576238434487, 0.178368498167787, -0.07067861581598903, 0.09623966252266039, -0.11204154931399371, -0.05065475304585276, 0.01256496306443866, 0.36094521554315695, -0.2544079855135921, -0.32307347759587285, 0.056055615896955645, -0.2774736167871595, -0.04413007327016392, 0.21055436501609942, 0.025284428213838882, -0.007212976389068333, 0.01852840566626763, -0.0553661201896, -0.009342963113889425, -0.287635935377115, 0.29687246287237284, 0.20455776663359754, 0.23358756985433812, 0.05157905871537836, 0.08597830559388833, -0.061541131631072075, -0.122928038870375, -0.032710872054065705, -0.1287335647384554, 0.05093227309085781, 0.1777852621886553, 0.13933014021222753, 0.17601967630006612, -0.3848016199565703, -0.2473906545775346, 0.16624428450466833, 0.1671316950487548, 0.10007920400196609, 0.0008313692634075468, -0.2648830282489001, 0.041463344040582134, -0.13807980504535, -0.10286834302748885, 0.002844359261125395, 0.010876529903713322, -0.02647660250350627, -0.24163100084349995, 0.11028015366562295, 0.042466020023006056, 0.00321019500545505, -0.012072585630960213, -0.05849910616951948, -0.004754532412904817, 0.09864606159365809, 0.022969903018269774, 0.03099036091146776, 0.16364921861696208, -0.15190477134801517, -0.04433803446483605, 0.4050694123921221, -0.10383608482150664, -0.04541951164920827, 0.1317796348524387, -0.2280094163333525, -0.15885651823184732, 0.13991829230716185, 0.18159927280425536, 0.0454492555987004, -0.1283144126817893, 0.0836498630402099, 0.007541944870450598, 0.23722404087056762, 0.10108880404799249, 0.058276930186588506, 0.30483300230264115, 0.14610456699003307, 0.09106863411958865, 0.08564652941964378, -0.1592734778481793, 0.030931035570386144, -0.2748618409803946, -0.06287701684467707, -0.18167867632325274, 0.11719250430037538, -0.12801043630848813, -0.11555757637946837, 0.408625024868699, 0.1950149867745478, 0.24072071340381412, 0.061319722916312894, 0.37274463477325603, 0.09031448877724488, 0.06372088245931617, 0.05131999882901611, 0.30787722483139984, 0.1375671367789726, 0.11119957589265388, -0.2639441880052008, 0.04743063136342964, -0.02458247185946541]
|
1,803.07037
|
High Speed and Low Power Sensing Schemes for STT-MRAM with IPMTJs
|
STT-MRAM with interfacial-anisotropy-type perpendicular MTJ (IPMTJ) is a
powerful candidate for the low switching energy design of STT-MRAM. In the
literature, the reading operation of STT-MRAM structured with IPMTJs have been
not studied until this time, in our knowledge. We investigated the reading
operation of STT-MRAM structured with IPMTJs. To enumerate the read operations
of the NVSenseAmp have successfully been performed a 2.5X reduction in average
low power and a 13X increase in average high speed compared with the previous
works.
|
cs.ET
|
sttmram with interfacialanisotropytype perpendicular mtj ipmtj is a powerful candidate for the low switching energy design of sttmram in the literature the reading operation of sttmram structured with ipmtjs have been not studied until this time in our knowledge we investigated the reading operation of sttmram structured with ipmtjs to enumerate the read operations of the nvsenseamp have successfully been performed a 25x reduction in average low power and a 13x increase in average high speed compared with the previous works
|
[['sttmram', 'with', 'interfacialanisotropytype', 'perpendicular', 'mtj', 'ipmtj', 'is', 'a', 'powerful', 'candidate', 'for', 'the', 'low', 'switching', 'energy', 'design', 'of', 'sttmram', 'in', 'the', 'literature', 'the', 'reading', 'operation', 'of', 'sttmram', 'structured', 'with', 'ipmtjs', 'have', 'been', 'not', 'studied', 'until', 'this', 'time', 'in', 'our', 'knowledge', 'we', 'investigated', 'the', 'reading', 'operation', 'of', 'sttmram', 'structured', 'with', 'ipmtjs', 'to', 'enumerate', 'the', 'read', 'operations', 'of', 'the', 'nvsenseamp', 'have', 'successfully', 'been', 'performed', 'a', '25x', 'reduction', 'in', 'average', 'low', 'power', 'and', 'a', '13x', 'increase', 'in', 'average', 'high', 'speed', 'compared', 'with', 'the', 'previous', 'works']]
|
[-0.13468112151971773, 0.08511878482654299, -0.02677494755602981, -0.03683081866811814, -0.06001838490881614, -0.14040388016789956, 0.08978991467799795, 0.43153365593599646, -0.2156520548619722, -0.4013265305149712, 0.11333216187593184, -0.23421656956749135, -0.05655206056728371, 0.23313012488774562, -0.07243808686096025, 0.09058251733107395, 0.03090881443533458, 0.03691590104350134, -0.07001824744388853, -0.30218358046228166, 0.13556107709270068, 0.1607563726260866, 0.3734053141486488, -0.003382893953178274, 0.12426162033807486, -0.034017631652348335, -0.025622770950002104, 0.023832927306341987, -0.06124665970319735, 0.09089186886251953, 0.2731774013097349, 0.06609350129790408, 0.27135173496054976, -0.4782160622753987, -0.21120088255204456, 0.04117371803946107, 0.11143067081023841, 0.11046669282950461, -0.08010785036420107, -0.17898515977063462, 0.17004021224075636, -0.2159108629842338, -0.06199630561260212, -0.06370765978078309, 0.04095595055504849, 0.05899443186966604, -0.22990602262832813, 0.002152010443081197, 0.06693270469795128, 0.07564159037888442, -0.011742591542363363, -0.14716782063049705, 0.026346159225795418, 0.11853181208655435, 0.025704909554118978, 0.09134827869772714, 0.1247435582764937, -0.12968585018595485, -0.1744299356237446, 0.3203295391837233, -0.05232536698397445, -0.18477648758868637, 0.14536166131055275, -0.12635919048548921, -0.11951215420604537, 0.14709404824105532, 0.16903880687038364, 0.11371982812048181, -0.14682369602317186, 0.06551597980586321, 0.021683183890816412, 0.18206256904982424, 0.08160689456915286, 0.046933986749009865, 0.14931874609503307, 0.25148809777180614, 0.02369002147430652, 0.183197696111165, -0.11746585349503316, -0.06606451044545363, -0.16420775670313129, -0.14155593741145966, -0.16556511022530399, 0.05514774418004795, -0.04771131095702386, -0.1214535532605001, 0.40131900488938155, 0.16746630455906453, 0.1865948077328013, 0.037524295076237696, 0.37361043262736576, 0.12609199666889923, 0.17292153186128034, 0.10865339643542508, 0.2522927907442576, 0.11944797736788659, 0.17880195189316414, -0.20262288513568869, 0.09218430361636963, -0.0845209400806772]
|
1,803.07038
|
Controlling Decoding for More Abstractive Summaries with Copy-Based
Networks
|
Attention-based neural abstractive summarization systems equipped with copy
mechanisms have shown promising results. Despite this success, it has been
noticed that such a system generates a summary by mostly, if not entirely,
copying over phrases, sentences, and sometimes multiple consecutive sentences
from an input paragraph, effectively performing extractive summarization. In
this paper, we verify this behavior using the latest neural abstractive
summarization system - a pointer-generator network. We propose a simple
baseline method that allows us to control the amount of copying without
retraining. Experiments indicate that the method provides a strong baseline for
abstractive systems looking to obtain high ROUGE scores while minimizing
overlap with the source article, substantially reducing the n-gram overlap with
the original article while keeping within 2 points of the original model's
ROUGE score.
|
cs.CL
|
attentionbased neural abstractive summarization systems equipped with copy mechanisms have shown promising results despite this success it has been noticed that such a system generates a summary by mostly if not entirely copying over phrases sentences and sometimes multiple consecutive sentences from an input paragraph effectively performing extractive summarization in this paper we verify this behavior using the latest neural abstractive summarization system a pointergenerator network we propose a simple baseline method that allows us to control the amount of copying without retraining experiments indicate that the method provides a strong baseline for abstractive systems looking to obtain high rouge scores while minimizing overlap with the source article substantially reducing the ngram overlap with the original article while keeping within 2 points of the original models rouge score
|
[['attentionbased', 'neural', 'abstractive', 'summarization', 'systems', 'equipped', 'with', 'copy', 'mechanisms', 'have', 'shown', 'promising', 'results', 'despite', 'this', 'success', 'it', 'has', 'been', 'noticed', 'that', 'such', 'a', 'system', 'generates', 'a', 'summary', 'by', 'mostly', 'if', 'not', 'entirely', 'copying', 'over', 'phrases', 'sentences', 'and', 'sometimes', 'multiple', 'consecutive', 'sentences', 'from', 'an', 'input', 'paragraph', 'effectively', 'performing', 'extractive', 'summarization', 'in', 'this', 'paper', 'we', 'verify', 'this', 'behavior', 'using', 'the', 'latest', 'neural', 'abstractive', 'summarization', 'system', 'a', 'pointergenerator', 'network', 'we', 'propose', 'a', 'simple', 'baseline', 'method', 'that', 'allows', 'us', 'to', 'control', 'the', 'amount', 'of', 'copying', 'without', 'retraining', 'experiments', 'indicate', 'that', 'the', 'method', 'provides', 'a', 'strong', 'baseline', 'for', 'abstractive', 'systems', 'looking', 'to', 'obtain', 'high', 'rouge', 'scores', 'while', 'minimizing', 'overlap', 'with', 'the', 'source', 'article', 'substantially', 'reducing', 'the', 'ngram', 'overlap', 'with', 'the', 'original', 'article', 'while', 'keeping', 'within', '2', 'points', 'of', 'the', 'original', 'models', 'rouge', 'score']]
|
[-0.07568974429432274, 0.02861006429259305, -0.06721553238821798, 0.0841261849732291, -0.12132086509518558, -0.18564419562244439, 0.08412820040484803, 0.4553530670236796, -0.23687811827403493, -0.33201685417589033, 0.006272508307120006, -0.3209053958290724, -0.15433550318448397, 0.1707518471266667, -0.13290738136447544, 0.0809686750817491, 0.18480512865062337, 0.06514776089974816, -0.043681497721991036, -0.3253547693093424, 0.27957884169518366, 0.07647280556557234, 0.36413967116823187, 0.01948315331719641, 0.14883288721102872, -0.012277787687708042, -0.05228432577860076, -0.011869794937410916, -0.029201077936647835, 0.15942665939655853, 0.3033149588294748, 0.21675765104555467, 0.33449167979415506, -0.3629626298134099, -0.23452228314181411, 0.08534489400699385, 0.152578282461036, 0.15284434466229868, -0.04218428995227441, -0.33526796111846124, 0.10182019613785087, -0.22416923011041945, 0.05777087064416264, -0.14935254800366238, -0.010114637356309686, 0.0007243249174280209, -0.25747042332659476, 0.010394593837190769, 0.14324314634359325, 0.0673360662003688, -0.015638743364888796, -0.1151758836585941, 0.03159238404077769, 0.14085515113038127, 0.07089532841155233, 0.14344480286672479, 0.07494762077840278, -0.15230795818752085, -0.17289075255030184, 0.3580057187646162, -0.0910119490345096, -0.2297757974920387, 0.1752218547111397, -0.028939436673681485, -0.14546027165852138, 0.0953891001881857, 0.1515436024419614, 0.07746759844303597, -0.19112790430517634, -0.026257648562477698, -0.06276580403027765, 0.2634943196317181, 0.09369279531892971, 0.006450476957979845, 0.2254523365845671, 0.2538292043345791, -0.012646225297430647, 0.14080223236487655, -0.07052657092026493, -0.047956899798009545, -0.20618686260104369, -0.08663513311284987, -0.16304532610593014, 0.002442068672394271, -0.06105493888014735, -0.1627769308877305, 0.43277862223112606, 0.25961778450437123, 0.20285608692938695, 0.15191323830003967, 0.3350462532398524, 0.023613713921804447, 0.12065214222366194, 0.09345102499537461, 0.15807162009150488, -0.046449004319583764, 0.1389400738689801, -0.13664633588086872, 0.12337906379252672, 0.09371374403053778]
|
1,803.07039
|
Batched quantum state exponentiation and quantum Hebbian learning
|
Machine learning is a crucial aspect of artificial intelligence. This paper
details an approach for quantum Hebbian learning through a batched version of
quantum state exponentiation. Here, batches of quantum data are interacted with
learning and processing quantum bits (qubits) by a series of elementary
controlled partial swap operations, resulting in a Hamiltonian simulation of
the statistical ensemble of the data. We decompose this elementary operation
into one and two qubit quantum gates from the Clifford+T set and use the
decomposition to perform an efficiency analysis. Our construction of quantum
Hebbian learning is motivated by extension from the established classical
approach, and it can be used to find details about the data such as eigenvalues
through phase estimation. This work contributes to the near-term development
and implementation of quantum machine learning techniques.
|
quant-ph
|
machine learning is a crucial aspect of artificial intelligence this paper details an approach for quantum hebbian learning through a batched version of quantum state exponentiation here batches of quantum data are interacted with learning and processing quantum bits qubits by a series of elementary controlled partial swap operations resulting in a hamiltonian simulation of the statistical ensemble of the data we decompose this elementary operation into one and two qubit quantum gates from the cliffordt set and use the decomposition to perform an efficiency analysis our construction of quantum hebbian learning is motivated by extension from the established classical approach and it can be used to find details about the data such as eigenvalues through phase estimation this work contributes to the nearterm development and implementation of quantum machine learning techniques
|
[['machine', 'learning', 'is', 'a', 'crucial', 'aspect', 'of', 'artificial', 'intelligence', 'this', 'paper', 'details', 'an', 'approach', 'for', 'quantum', 'hebbian', 'learning', 'through', 'a', 'batched', 'version', 'of', 'quantum', 'state', 'exponentiation', 'here', 'batches', 'of', 'quantum', 'data', 'are', 'interacted', 'with', 'learning', 'and', 'processing', 'quantum', 'bits', 'qubits', 'by', 'a', 'series', 'of', 'elementary', 'controlled', 'partial', 'swap', 'operations', 'resulting', 'in', 'a', 'hamiltonian', 'simulation', 'of', 'the', 'statistical', 'ensemble', 'of', 'the', 'data', 'we', 'decompose', 'this', 'elementary', 'operation', 'into', 'one', 'and', 'two', 'qubit', 'quantum', 'gates', 'from', 'the', 'cliffordt', 'set', 'and', 'use', 'the', 'decomposition', 'to', 'perform', 'an', 'efficiency', 'analysis', 'our', 'construction', 'of', 'quantum', 'hebbian', 'learning', 'is', 'motivated', 'by', 'extension', 'from', 'the', 'established', 'classical', 'approach', 'and', 'it', 'can', 'be', 'used', 'to', 'find', 'details', 'about', 'the', 'data', 'such', 'as', 'eigenvalues', 'through', 'phase', 'estimation', 'this', 'work', 'contributes', 'to', 'the', 'nearterm', 'development', 'and', 'implementation', 'of', 'quantum', 'machine', 'learning', 'techniques']]
|
[-0.06903202608792168, 0.11351670432949587, -0.10791690520603549, 0.026064781130337382, -0.06036564245269718, -0.17641121984695818, 0.07021096282705637, 0.354666870814099, -0.3063605990380783, -0.3234925237343167, 0.08999169995888334, -0.24829298821560136, -0.18610821569172636, 0.22986698330549354, -0.08773822445161358, 0.11981215664524246, 0.11570265889873332, 0.03935191223651848, -0.052748230285942554, -0.2768789088551068, 0.27245796666565264, 0.05333133689639384, 0.3005972319568338, -0.02271438963869128, 0.11941582803300468, 0.03732652819687218, -0.0032367609903413913, -0.05979306610551606, -0.0692664224012388, 0.18364739722826265, 0.3202301903317372, 0.20081229355172114, 0.3124383593923553, -0.4573520524921178, -0.17601383458553976, 0.07115999801934583, 0.13210642495488917, 0.16026116687465797, -0.04110492482273416, -0.3084271627647633, 0.03331778942127571, -0.17928616421395968, -0.022138580521145326, -0.16256770959377967, -0.03455921599048783, -0.06567526444496252, -0.24915213360685756, -0.011579492528019755, 0.11128350773607522, 0.09452592525243138, 0.03236812661634758, -0.07009061646760639, 0.09762626077457698, 0.11397755375329519, -0.050210304745247195, 0.021172658395671257, 0.19840761579248603, -0.12220461909821483, -0.22593278602950953, 0.3343051857822998, -0.010000580203874657, -0.18619774036095338, 0.1389060692410126, 0.0010564447765125697, -0.1519431602280361, 0.0492765221420224, 0.1832384101651383, 0.0809325939679349, -0.15770267042557173, 0.09126936172084021, 0.023885737215592104, 0.1894817719038463, 0.0028749373847280035, 0.030868851431560786, 0.17615861655918486, 0.19203943356159003, 0.038631574822251095, 0.17473870019029797, -0.053321861423848364, -0.18495588204258998, -0.2977992932763741, -0.19521610671147233, -0.24000935101084356, 0.10012986448286525, -0.06882524888163916, -0.14567819419475694, 0.39179629965501866, 0.17761439697818732, 0.17081566410717752, 0.033445835702657474, 0.35583625903183763, 0.10778969048205357, 0.08783374148223436, 0.08833736700718432, 0.17676205702115444, 0.1661640445835832, 0.09438817037417638, -0.23518351177512103, 0.025840976587708363, 0.05282060997948671]
|
1,803.0704
|
Habitability from Tidally-Induced Tectonics
|
The stability of Earth's climate on geological timescales is enabled by the
carbon-silicate cycle that acts as a negative feedback mechanism stabilizing
surface temperatures via the intake and outgas of atmospheric carbon. On Earth,
this thermostat is enabled by plate tectonics that sequesters outgassed CO2
back into the mantle via weathering and subduction at convergent margins. Here
we propose a separate tectonic mechanism -- vertical recycling -- that can
serve as the vehicle for CO2 outgassing and sequestration over long timescales.
The mechanism requires continuous tidal heating, which makes it particularly
relevant to planets in the habitable zone of M stars. Dynamical models of this
vertical recycling scenario and stability analysis show that temperate climates
stable over Gy timescales are realized for a variety of initial conditions,
even as the M star dims over time. The magnitude of equilibrium surface
temperatures depends on the interplay of sea weathering and outgassing, which
in turn depends on planetary carbon content, so that planets with lower carbon
budgets are favoured for temperate conditions. Habitability of planets such as
found in the Trappist-1 may be rooted in tidally-driven tectonics.
|
astro-ph.EP
|
the stability of earths climate on geological timescales is enabled by the carbonsilicate cycle that acts as a negative feedback mechanism stabilizing surface temperatures via the intake and outgas of atmospheric carbon on earth this thermostat is enabled by plate tectonics that sequesters outgassed co2 back into the mantle via weathering and subduction at convergent margins here we propose a separate tectonic mechanism vertical recycling that can serve as the vehicle for co2 outgassing and sequestration over long timescales the mechanism requires continuous tidal heating which makes it particularly relevant to planets in the habitable zone of m stars dynamical models of this vertical recycling scenario and stability analysis show that temperate climates stable over gy timescales are realized for a variety of initial conditions even as the m star dims over time the magnitude of equilibrium surface temperatures depends on the interplay of sea weathering and outgassing which in turn depends on planetary carbon content so that planets with lower carbon budgets are favoured for temperate conditions habitability of planets such as found in the trappist1 may be rooted in tidallydriven tectonics
|
[['the', 'stability', 'of', 'earths', 'climate', 'on', 'geological', 'timescales', 'is', 'enabled', 'by', 'the', 'carbonsilicate', 'cycle', 'that', 'acts', 'as', 'a', 'negative', 'feedback', 'mechanism', 'stabilizing', 'surface', 'temperatures', 'via', 'the', 'intake', 'and', 'outgas', 'of', 'atmospheric', 'carbon', 'on', 'earth', 'this', 'thermostat', 'is', 'enabled', 'by', 'plate', 'tectonics', 'that', 'sequesters', 'outgassed', 'co2', 'back', 'into', 'the', 'mantle', 'via', 'weathering', 'and', 'subduction', 'at', 'convergent', 'margins', 'here', 'we', 'propose', 'a', 'separate', 'tectonic', 'mechanism', 'vertical', 'recycling', 'that', 'can', 'serve', 'as', 'the', 'vehicle', 'for', 'co2', 'outgassing', 'and', 'sequestration', 'over', 'long', 'timescales', 'the', 'mechanism', 'requires', 'continuous', 'tidal', 'heating', 'which', 'makes', 'it', 'particularly', 'relevant', 'to', 'planets', 'in', 'the', 'habitable', 'zone', 'of', 'm', 'stars', 'dynamical', 'models', 'of', 'this', 'vertical', 'recycling', 'scenario', 'and', 'stability', 'analysis', 'show', 'that', 'temperate', 'climates', 'stable', 'over', 'gy', 'timescales', 'are', 'realized', 'for', 'a', 'variety', 'of', 'initial', 'conditions', 'even', 'as', 'the', 'm', 'star', 'dims', 'over', 'time', 'the', 'magnitude', 'of', 'equilibrium', 'surface', 'temperatures', 'depends', 'on', 'the', 'interplay', 'of', 'sea', 'weathering', 'and', 'outgassing', 'which', 'in', 'turn', 'depends', 'on', 'planetary', 'carbon', 'content', 'so', 'that', 'planets', 'with', 'lower', 'carbon', 'budgets', 'are', 'favoured', 'for', 'temperate', 'conditions', 'habitability', 'of', 'planets', 'such', 'as', 'found', 'in', 'the', 'trappist1', 'may', 'be', 'rooted', 'in', 'tidallydriven', 'tectonics']]
|
[-0.12255333559485254, 0.2552951086404641, -0.055600401015368874, 0.04863806849775406, -0.06022401850422394, -0.05866963683261669, 0.10583357945270709, 0.35153044285355034, -0.23310449996906854, -0.28241356516482086, 0.15010408963752234, -0.18737872281997045, -0.1291897443102693, 0.24367280504768613, -0.09549437716071095, -0.029722189931147783, 0.0994781307712361, -0.05406063579081732, 0.004594264956252588, -0.2691744980504634, 0.24529262327916593, 0.10070736654317723, 0.14149014520136496, 0.07676342911353069, 0.07253116492251098, -0.11575764033349824, 0.017010683101694006, -0.06566407247945401, -0.166961452851955, 0.024043796174637564, 0.250592256431436, 0.11407177659918319, 0.24007432133497947, -0.488176117463109, -0.2989592163946357, 0.07375872155646973, 0.09235069763867164, 0.009154823948987402, -0.02556113642384554, -0.19692755361077385, 0.027293133416346142, -0.194285835566736, -0.1158198504273749, -0.008706962740289273, 0.08803650827382456, -0.003078962655948359, -0.28187687881930557, 0.07903103653090791, 0.10209416191699366, 0.144266474019777, -0.17331592651636718, -0.14649870643228458, -0.17038519998147553, 0.10521826531052343, 0.06417617097415113, -0.02481544987876787, 0.25663967369697416, -0.05899480758631438, 0.02174863130446513, 0.41967556125146677, -0.13858948005452895, -0.10054954745842573, 0.2717339385922609, -0.15932639893067613, -0.07031569059856319, 0.1629807806604511, 0.18489780698667516, 0.1356054194844686, -0.14158645762990302, 0.0027801133334063566, -0.017634109652775166, 0.1331850251868613, 0.12788102389466796, -0.00034615158737933896, 0.3595233232008068, 0.23176923670273805, 0.1525869031365101, 0.051551400422205594, -0.15812478250066575, -0.10244213962149652, -0.16706535814248108, -0.1646433033440569, -0.08563630380744504, 0.05771803831909322, -0.07025143014902574, -0.17749767477757164, 0.3304311098642187, 0.13581634302186052, 0.12732738453465012, -0.006849694312652471, 0.2918048317308773, 0.033003484548816645, 0.09528580058307214, 0.06789720408454701, 0.2672897028720139, 0.10144859569717792, 0.08957850063733941, -0.2794248130540926, 0.20339423462916115, 0.03586133759581371]
|
1,803.07041
|
Spatial risk measures and rate of spatial diversification
|
An accurate assessment of the risk of extreme environmental events is of
great importance for populations, authorities and the
banking/insurance/reinsurance industry. Koch (2017) introduced a notion of
spatial risk measure and a corresponding set of axioms which are well suited to
analyze the risk due to events having a spatial extent, precisely such as
environmental phenomena. The axiom of asymptotic spatial homogeneity is of
particular interest since it allows one to quantify the rate of spatial
diversification when the region under consideration becomes large. In this
paper, we first investigate the general concepts of spatial risk measures and
corresponding axioms further and thoroughly explain the usefulness of this
theory for both actuarial science and practice. Second, in the case of a
general cost field, we give sufficient conditions such that spatial risk
measures associated with expectation, variance, Value-at-Risk as well as
expected shortfall and induced by this cost field satisfy the axioms of
asymptotic spatial homogeneity of order $0$, $-2$, $-1$ and $-1$, respectively.
Last but not least, in the case where the cost field is a function of a
max-stable random field, we provide conditions on both the function and the
max-stable field ensuring the latter properties. Max-stable random fields are
relevant when assessing the risk of extreme events since they appear as a
natural extension of multivariate extreme-value theory to the level of random
fields. Overall, this paper improves our understanding of spatial risk measures
as well as of their properties with respect to the space variable and
generalizes many results obtained in Koch (2017).
|
q-fin.RM
|
an accurate assessment of the risk of extreme environmental events is of great importance for populations authorities and the bankinginsurancereinsurance industry koch 2017 introduced a notion of spatial risk measure and a corresponding set of axioms which are well suited to analyze the risk due to events having a spatial extent precisely such as environmental phenomena the axiom of asymptotic spatial homogeneity is of particular interest since it allows one to quantify the rate of spatial diversification when the region under consideration becomes large in this paper we first investigate the general concepts of spatial risk measures and corresponding axioms further and thoroughly explain the usefulness of this theory for both actuarial science and practice second in the case of a general cost field we give sufficient conditions such that spatial risk measures associated with expectation variance valueatrisk as well as expected shortfall and induced by this cost field satisfy the axioms of asymptotic spatial homogeneity of order 0 2 1 and 1 respectively last but not least in the case where the cost field is a function of a maxstable random field we provide conditions on both the function and the maxstable field ensuring the latter properties maxstable random fields are relevant when assessing the risk of extreme events since they appear as a natural extension of multivariate extremevalue theory to the level of random fields overall this paper improves our understanding of spatial risk measures as well as of their properties with respect to the space variable and generalizes many results obtained in koch 2017
|
[['an', 'accurate', 'assessment', 'of', 'the', 'risk', 'of', 'extreme', 'environmental', 'events', 'is', 'of', 'great', 'importance', 'for', 'populations', 'authorities', 'and', 'the', 'bankinginsurancereinsurance', 'industry', 'koch', '2017', 'introduced', 'a', 'notion', 'of', 'spatial', 'risk', 'measure', 'and', 'a', 'corresponding', 'set', 'of', 'axioms', 'which', 'are', 'well', 'suited', 'to', 'analyze', 'the', 'risk', 'due', 'to', 'events', 'having', 'a', 'spatial', 'extent', 'precisely', 'such', 'as', 'environmental', 'phenomena', 'the', 'axiom', 'of', 'asymptotic', 'spatial', 'homogeneity', 'is', 'of', 'particular', 'interest', 'since', 'it', 'allows', 'one', 'to', 'quantify', 'the', 'rate', 'of', 'spatial', 'diversification', 'when', 'the', 'region', 'under', 'consideration', 'becomes', 'large', 'in', 'this', 'paper', 'we', 'first', 'investigate', 'the', 'general', 'concepts', 'of', 'spatial', 'risk', 'measures', 'and', 'corresponding', 'axioms', 'further', 'and', 'thoroughly', 'explain', 'the', 'usefulness', 'of', 'this', 'theory', 'for', 'both', 'actuarial', 'science', 'and', 'practice', 'second', 'in', 'the', 'case', 'of', 'a', 'general', 'cost', 'field', 'we', 'give', 'sufficient', 'conditions', 'such', 'that', 'spatial', 'risk', 'measures', 'associated', 'with', 'expectation', 'variance', 'valueatrisk', 'as', 'well', 'as', 'expected', 'shortfall', 'and', 'induced', 'by', 'this', 'cost', 'field', 'satisfy', 'the', 'axioms', 'of', 'asymptotic', 'spatial', 'homogeneity', 'of', 'order', '0', '2', '1', 'and', '1', 'respectively', 'last', 'but', 'not', 'least', 'in', 'the', 'case', 'where', 'the', 'cost', 'field', 'is', 'a', 'function', 'of', 'a', 'maxstable', 'random', 'field', 'we', 'provide', 'conditions', 'on', 'both', 'the', 'function', 'and', 'the', 'maxstable', 'field', 'ensuring', 'the', 'latter', 'properties', 'maxstable', 'random', 'fields', 'are', 'relevant', 'when', 'assessing', 'the', 'risk', 'of', 'extreme', 'events', 'since', 'they', 'appear', 'as', 'a', 'natural', 'extension', 'of', 'multivariate', 'extremevalue', 'theory', 'to', 'the', 'level', 'of', 'random', 'fields', 'overall', 'this', 'paper', 'improves', 'our', 'understanding', 'of', 'spatial', 'risk', 'measures', 'as', 'well', 'as', 'of', 'their', 'properties', 'with', 'respect', 'to', 'the', 'space', 'variable', 'and', 'generalizes', 'many', 'results', 'obtained', 'in', 'koch', '2017']]
|
[-0.06435868280004797, 0.08595703295173962, -0.07650690795890114, 0.14627835785495336, -0.03678255335034919, -0.07477034603471111, 0.04062195116375733, 0.3521078256198962, -0.24381862276140964, -0.2942423260385567, 0.13634073053572138, -0.2305272605607911, -0.15654742037622782, 0.1630131167194122, -0.1462701459023492, 0.06297929634274624, -0.010864912614124478, 0.05763425764155272, -0.01600081950095955, -0.25642066819818865, 0.33098729401399396, 0.0854277796970564, 0.3077641599520575, 0.056811524759496024, 0.10381791299187171, 0.023985516962056863, -0.04686589645825734, 0.05685967128363245, -0.12044433505175789, 0.12827307902443863, 0.25884845250402577, 0.17448646743832796, 0.35984936126624234, -0.3758651222242406, -0.2143419013127641, 0.15248343379425933, 0.0717553197171128, 0.03712676548138916, 0.008451395373413106, -0.2855626527143613, 0.04815435496266218, -0.14500172174848558, -0.1669282021757681, -0.07375683897316776, 0.024840650840360468, 0.05544123270738055, -0.31290005903974816, 0.09520547460033413, 0.08150452853669776, 0.10354480131718447, -0.04428970651429154, -0.10908128767277958, -0.022822617547717527, 0.13193548723506865, 0.11742914753176592, 0.015103963837077572, 0.12108672491376637, -0.14924882973900822, -0.12261912990152268, 0.36729093382382416, -0.04625555116081159, -0.19354034123171004, 0.20198584467834735, -0.18702713189304632, -0.14775030917371623, 0.07792988333312678, 0.19296066261449596, 0.09317207732055977, -0.17179868143887234, 0.09762045307957123, -0.005541822480154224, 0.10794509963307064, 0.08223169075426995, 0.0990101205748033, 0.14890884081614786, 0.15350385511283093, 0.0975171158363537, 0.13150602026234992, -0.07761370408775292, -0.10479505883995444, -0.31236099926536554, -0.17401412734437827, -0.15483637087436364, 0.031197993384978417, -0.13776542497129185, -0.18275414780146093, 0.4005398712374699, 0.17603144467830134, 0.1810295554005279, 0.07547131828187048, 0.26167871766574535, 0.13522153111790658, 0.020350132813746313, 0.04149831818540406, 0.18275557343986293, 0.13657203309185206, 0.07596282992017223, -0.13634502340494237, 0.11863771169169013, 0.017349468587781303]
|
1,803.07042
|
On the $k$-independence number of graphs
|
This paper generalizes and unifies the existing spectral bounds on the
$k$-independence number of a graph, which is the maximum size of a set of
vertices at pairwise distance greater than $k$. The previous bounds known in
the literature follow as a corollary of the main results in this work. We show
that for most cases our bounds outperform the previous known bounds. Some
infinite graphs where the bounds are tight are also presented. Finally, as a
byproduct, we derive some lower spectral bounds for the diameter of a graph.
|
math.CO
|
this paper generalizes and unifies the existing spectral bounds on the kindependence number of a graph which is the maximum size of a set of vertices at pairwise distance greater than k the previous bounds known in the literature follow as a corollary of the main results in this work we show that for most cases our bounds outperform the previous known bounds some infinite graphs where the bounds are tight are also presented finally as a byproduct we derive some lower spectral bounds for the diameter of a graph
|
[['this', 'paper', 'generalizes', 'and', 'unifies', 'the', 'existing', 'spectral', 'bounds', 'on', 'the', 'kindependence', 'number', 'of', 'a', 'graph', 'which', 'is', 'the', 'maximum', 'size', 'of', 'a', 'set', 'of', 'vertices', 'at', 'pairwise', 'distance', 'greater', 'than', 'k', 'the', 'previous', 'bounds', 'known', 'in', 'the', 'literature', 'follow', 'as', 'a', 'corollary', 'of', 'the', 'main', 'results', 'in', 'this', 'work', 'we', 'show', 'that', 'for', 'most', 'cases', 'our', 'bounds', 'outperform', 'the', 'previous', 'known', 'bounds', 'some', 'infinite', 'graphs', 'where', 'the', 'bounds', 'are', 'tight', 'are', 'also', 'presented', 'finally', 'as', 'a', 'byproduct', 'we', 'derive', 'some', 'lower', 'spectral', 'bounds', 'for', 'the', 'diameter', 'of', 'a', 'graph']]
|
[-0.09625320192426443, 0.0747132971106718, -0.058753073034394115, 0.06489966360515811, -0.0925574325904664, -0.08987522581074801, 0.0732288703490566, 0.3186034228445755, -0.19155444961118823, -0.3515259119371573, 0.12683474100970973, -0.2928060552519229, -0.1614768885076046, 0.2720356434506054, -0.10132793387035943, 0.032018718761133234, 0.06453377660363913, 0.12010705079883337, -0.07669272315559081, -0.2861972901692045, 0.29634947397797884, 0.02411420030726327, 0.2045195787731144, 0.12112763989716768, 0.021352637688525848, -0.035964150638836956, -0.03124842064248191, 0.0468796846652266, -0.24880397972018625, 0.15201907039930423, 0.22745515503661914, 0.15584462145860825, 0.22632791760067145, -0.3550003542047408, -0.2097831526874668, 0.15684696862008424, 0.15943838544577982, 0.10322425258733953, -0.009816001041326673, -0.20606962652721753, 0.11574129865815243, -0.11792268865845269, -0.08158611005896496, 0.016125257333947554, 0.02344765103318625, 0.0657437099247343, -0.2874702005233202, 0.03254177675601871, 0.15978474493862854, 0.013058389806085162, -0.00970131940363596, -0.2438510079919878, 0.034407533336586006, 0.11553589247374071, 0.020282218628562988, 0.014283043534184496, 0.03672508931485936, -0.08165218390899504, -0.16008398233809404, 0.320515794493258, -0.07748767272197357, -0.1666109445427234, 0.18322505809677145, -0.13110771007421945, -0.1995429074081282, 0.0653377617812819, 0.16496511631541783, 0.18446904178708792, -0.10931198348601659, 0.10467332115125222, -0.1713763950392604, 0.11173049990191228, 0.09973741095099184, 0.11375312632881104, 0.05318030325902833, 0.14256530166086223, 0.17784126893901783, 0.19500109061547038, -0.03821359467951374, -0.051817130224986206, -0.348879408919149, -0.11027815407142043, -0.24175303435056575, -0.008588400886704524, -0.18801315333160648, -0.14727697455479452, 0.38807845252255596, 0.15921244977249038, 0.25721853652762044, 0.21464612543091385, 0.30341311415864364, 0.09012673078379724, 0.04107431556719045, 0.16539797944844598, 0.23578742160267818, 0.15919172978028656, -0.007762100221589208, -0.1253650463341425, 0.06902073817327618, 0.09988214899268415]
|
1,803.07043
|
Projective Splitting with Forward Steps: Asynchronous and
Block-Iterative Operator Splitting
|
This work is concerned with the classical problem of finding a zero of a sum
of maximal monotone operators. For the projective splitting framework recently
proposed by Combettes and Eckstein, we show how to replace the fundamental
subproblem calculation using a backward step with one based on two forward
steps. The resulting algorithms have the same kind of coordination procedure
and can be implemented in the same block-iterative and highly flexible manner,
but may perform backward steps on some operators and forward steps on others.
Prior algorithms in the projective splitting family have used only backward
steps. Forward steps can be used for any Lipschitz-continuous operators
provided the stepsize is bounded by the inverse of the Lipschitz constant. If
the Lipschitz constant is unknown, a simple backtracking linesearch procedure
may be used. For affine operators, the stepsize can be chosen adaptively
without knowledge of the Lipschitz constant and without any additional forward
steps. We close the paper by empirically studying the performance of several
kinds of splitting algorithms on a large-scale rare feature selection problem.
|
math.OC cs.LG
|
this work is concerned with the classical problem of finding a zero of a sum of maximal monotone operators for the projective splitting framework recently proposed by combettes and eckstein we show how to replace the fundamental subproblem calculation using a backward step with one based on two forward steps the resulting algorithms have the same kind of coordination procedure and can be implemented in the same blockiterative and highly flexible manner but may perform backward steps on some operators and forward steps on others prior algorithms in the projective splitting family have used only backward steps forward steps can be used for any lipschitzcontinuous operators provided the stepsize is bounded by the inverse of the lipschitz constant if the lipschitz constant is unknown a simple backtracking linesearch procedure may be used for affine operators the stepsize can be chosen adaptively without knowledge of the lipschitz constant and without any additional forward steps we close the paper by empirically studying the performance of several kinds of splitting algorithms on a largescale rare feature selection problem
|
[['this', 'work', 'is', 'concerned', 'with', 'the', 'classical', 'problem', 'of', 'finding', 'a', 'zero', 'of', 'a', 'sum', 'of', 'maximal', 'monotone', 'operators', 'for', 'the', 'projective', 'splitting', 'framework', 'recently', 'proposed', 'by', 'combettes', 'and', 'eckstein', 'we', 'show', 'how', 'to', 'replace', 'the', 'fundamental', 'subproblem', 'calculation', 'using', 'a', 'backward', 'step', 'with', 'one', 'based', 'on', 'two', 'forward', 'steps', 'the', 'resulting', 'algorithms', 'have', 'the', 'same', 'kind', 'of', 'coordination', 'procedure', 'and', 'can', 'be', 'implemented', 'in', 'the', 'same', 'blockiterative', 'and', 'highly', 'flexible', 'manner', 'but', 'may', 'perform', 'backward', 'steps', 'on', 'some', 'operators', 'and', 'forward', 'steps', 'on', 'others', 'prior', 'algorithms', 'in', 'the', 'projective', 'splitting', 'family', 'have', 'used', 'only', 'backward', 'steps', 'forward', 'steps', 'can', 'be', 'used', 'for', 'any', 'lipschitzcontinuous', 'operators', 'provided', 'the', 'stepsize', 'is', 'bounded', 'by', 'the', 'inverse', 'of', 'the', 'lipschitz', 'constant', 'if', 'the', 'lipschitz', 'constant', 'is', 'unknown', 'a', 'simple', 'backtracking', 'linesearch', 'procedure', 'may', 'be', 'used', 'for', 'affine', 'operators', 'the', 'stepsize', 'can', 'be', 'chosen', 'adaptively', 'without', 'knowledge', 'of', 'the', 'lipschitz', 'constant', 'and', 'without', 'any', 'additional', 'forward', 'steps', 'we', 'close', 'the', 'paper', 'by', 'empirically', 'studying', 'the', 'performance', 'of', 'several', 'kinds', 'of', 'splitting', 'algorithms', 'on', 'a', 'largescale', 'rare', 'feature', 'selection', 'problem']]
|
[-0.10258465220220386, 0.06665590575763157, -0.07667725113885743, 0.05995201581689928, -0.12277578281238676, -0.18594476325836565, 0.0698755601427651, 0.41414077645965985, -0.3205631883947977, -0.25371347194271426, 0.12187374089112771, -0.20476055498201667, -0.1192197776798691, 0.19498933944318975, -0.06933040054248912, 0.12003593364996569, 0.08651168025032217, 0.016710093106542315, -0.06770941754287509, -0.26629296054198803, 0.3442805349986468, 0.020262179555637496, 0.2455679677639689, 0.021317002919635602, 0.14852355108862478, 0.007024830618341054, -0.051326121614214834, 0.02597760135041816, -0.08568719079318855, 0.11462311549245247, 0.2666938010024439, 0.12716158840007016, 0.34311564654111865, -0.4321775958420975, -0.18165878554540021, 0.14312562085688113, 0.17236602206581406, 0.10146383663905519, -0.044712607013726875, -0.2669046566369278, 0.09304616556436356, -0.08906246960711932, -0.09691968195406454, -0.0894545338089977, -0.04875305850058794, 0.031425036207905835, -0.2957687258228127, 0.002783974091123257, 0.09807717278865831, 0.02778586382046342, -0.009116376393607685, -0.13163016890308687, 0.02127475971089942, 0.10507599892094731, 0.030592652832024864, 0.04579615818070514, 0.09948537859533514, -0.037488037854699154, -0.16849122067913413, 0.3393886245659087, -0.0678669099769156, -0.28892892388893027, 0.12787988564265626, -0.06403998053233538, -0.14596771798229644, 0.10880926757252642, 0.16088007479773037, 0.19809134176000953, -0.14483618869579265, 0.10942433226155117, -0.025507719245340142, 0.12663987696436899, 0.06568336865731648, -0.02935049290635756, 0.08744978185477001, 0.12034873602778784, 0.14845157166942954, 0.11071466043325408, -0.0351055949088186, -0.09007386599800417, -0.32328196157967404, -0.1498751169735832, -0.1624225331310715, 0.007379543206521443, -0.11554471743251529, -0.1251740698303495, 0.3804874836866345, 0.1010963761084713, 0.2185879797767848, 0.08811467973082991, 0.3196723080479673, 0.15518050442316703, 0.09099591126266335, 0.08778708938509226, 0.21126576836703212, 0.08973856233991682, 0.09037869292444417, -0.21507355104865772, 0.13886441602770772, 0.15026614723352916]
|
1,803.07044
|
Positive neighborhoods of curves
|
In this work we study neighborhoods of curves in surfaces with positive
self-intersection that can be embeeded as a germ of neighborhood of a curve on
the projective plane.
|
math.CV
|
in this work we study neighborhoods of curves in surfaces with positive selfintersection that can be embeeded as a germ of neighborhood of a curve on the projective plane
|
[['in', 'this', 'work', 'we', 'study', 'neighborhoods', 'of', 'curves', 'in', 'surfaces', 'with', 'positive', 'selfintersection', 'that', 'can', 'be', 'embeeded', 'as', 'a', 'germ', 'of', 'neighborhood', 'of', 'a', 'curve', 'on', 'the', 'projective', 'plane']]
|
[-0.22877110301383904, -0.012403599352442793, -0.17028165329247713, 0.0007488135306630284, -0.0378660023478525, -0.07575250806153885, 0.08485846474234547, 0.36136388765381916, -0.2506083976311077, -0.2164389809061374, 0.07632776064565405, -0.29858777821729227, -0.1911474865462099, 0.26754412294498514, -0.19073213596961328, -0.023712474054523876, 0.053471835587905456, 0.03866909783183863, -0.09413299670476201, -0.2903733806950705, 0.4344568621101124, -0.05854402715340257, 0.15054917980783752, 0.05839835546378579, 0.07023179658322729, -0.007494554272852838, 0.10587567430255669, 0.10164468895111765, -0.16583189149683417, 0.16548628040722438, 0.26716785749054645, 0.10190636942362678, 0.17646671419164964, -0.38252983228968723, -0.2597285410655396, 0.25786585586943794, 0.17301153780759446, 0.048844221979379654, -0.030209056022743295, -0.1964798121979194, 0.11780588155878442, -0.02581451360934547, -0.21117190986738674, -0.03317502703742191, 0.06494360051250883, 0.09515455903186064, -0.13100143242627382, -0.016731270156534656, 0.07044398205886994, 0.20132400577754847, -0.021493856562301517, -0.012283936808151858, -0.10276381591601032, 0.05782517232000828, 0.020121253694274595, 0.1248660292351685, 0.11094876101040947, -0.0985565186378413, -0.0916955744448517, 0.33741898921185304, -0.1284572361037135, -0.23714594782463141, 0.10675298928150109, -0.2180372909642756, -0.09845295877728079, 0.1297624574508518, 0.2545019792658942, 0.21520643514980162, -0.07778035004490189, 0.14605565309258445, -0.11131713033786841, 0.09547768308714565, 0.10722192799273346, -0.08577896596398205, 0.22815543253506934, 0.12307969361011471, 0.10286686210227865, 0.11963884951546788, -0.07560269670128557, -0.03320059334925775, -0.4010271978165422, -0.29486676084343344, -0.1528329136989279, 0.12975001188793353, -0.08108956037488367, -0.21675396664068103, 0.46798648525561604, 0.020396953066145734, 0.3462329317948648, 0.07684501237235963, 0.25016756129584145, 0.035735420745498105, 0.01868943589007748, 0.04159847008330481, 0.15282003421868598, 0.08158271054604224, -0.044476727805366476, -0.14212547804761147, 0.06098417716566473, 0.12737146093110954]
|
1,803.07045
|
Non-global logarithms in jet and isolation cone cross sections
|
Starting from a factorization theorem in effective field theory, we derive a
parton-shower equation for the resummation of non-global logarithms. We have
implemented this shower and interfaced it with a tree-level event generator to
obtain an automated framework to resum the leading logarithm of non-global
observables in the large-$N_c$ limit. Using this setup, we compute gap
fractions for dijet processes and isolation cone cross sections relevant for
photon production. We compare our results with fixed-order computations and LHC
measurements. We find that naive exponentiation is often not adequate,
especially when the vetoed region is small, since non-global contributions are
enhanced due to their dependence on the veto-region size. Since our parton
shower is derived from first principles and based on renormalization-group
evolution, it is clear what ingredients will have to be included to perform
resummations at subleading logarithmic accuracy in the future.
|
hep-ph
|
starting from a factorization theorem in effective field theory we derive a partonshower equation for the resummation of nonglobal logarithms we have implemented this shower and interfaced it with a treelevel event generator to obtain an automated framework to resum the leading logarithm of nonglobal observables in the largen_c limit using this setup we compute gap fractions for dijet processes and isolation cone cross sections relevant for photon production we compare our results with fixedorder computations and lhc measurements we find that naive exponentiation is often not adequate especially when the vetoed region is small since nonglobal contributions are enhanced due to their dependence on the vetoregion size since our parton shower is derived from first principles and based on renormalizationgroup evolution it is clear what ingredients will have to be included to perform resummations at subleading logarithmic accuracy in the future
|
[['starting', 'from', 'a', 'factorization', 'theorem', 'in', 'effective', 'field', 'theory', 'we', 'derive', 'a', 'partonshower', 'equation', 'for', 'the', 'resummation', 'of', 'nonglobal', 'logarithms', 'we', 'have', 'implemented', 'this', 'shower', 'and', 'interfaced', 'it', 'with', 'a', 'treelevel', 'event', 'generator', 'to', 'obtain', 'an', 'automated', 'framework', 'to', 'resum', 'the', 'leading', 'logarithm', 'of', 'nonglobal', 'observables', 'in', 'the', 'largen_c', 'limit', 'using', 'this', 'setup', 'we', 'compute', 'gap', 'fractions', 'for', 'dijet', 'processes', 'and', 'isolation', 'cone', 'cross', 'sections', 'relevant', 'for', 'photon', 'production', 'we', 'compare', 'our', 'results', 'with', 'fixedorder', 'computations', 'and', 'lhc', 'measurements', 'we', 'find', 'that', 'naive', 'exponentiation', 'is', 'often', 'not', 'adequate', 'especially', 'when', 'the', 'vetoed', 'region', 'is', 'small', 'since', 'nonglobal', 'contributions', 'are', 'enhanced', 'due', 'to', 'their', 'dependence', 'on', 'the', 'vetoregion', 'size', 'since', 'our', 'parton', 'shower', 'is', 'derived', 'from', 'first', 'principles', 'and', 'based', 'on', 'renormalizationgroup', 'evolution', 'it', 'is', 'clear', 'what', 'ingredients', 'will', 'have', 'to', 'be', 'included', 'to', 'perform', 'resummations', 'at', 'subleading', 'logarithmic', 'accuracy', 'in', 'the', 'future']]
|
[-0.05754010535525621, 0.09516974273874633, -0.18333814327162526, 0.17353785922585702, -0.05960331733523478, -0.05829715937646832, 0.006164645710307774, 0.3782706779579744, -0.2000348180041612, -0.2714338264963094, 0.05875961255391148, -0.3158665395850408, -0.05619249309261217, 0.1550518075707666, 0.008595900842713536, 0.09764701740301036, 0.09430265845565773, -0.030505443312201307, -0.060468503833188615, -0.23241880548298888, 0.3035119153337936, 0.07275762547514276, 0.2261631080933602, 0.15952247104723938, 0.07945474113687767, 0.057046028316443696, -0.08995425223714691, -0.011530507788564084, -0.12421742613029589, 0.06501520487169425, 0.29949316438386575, 0.05538686360265558, 0.14176621882026977, -0.4022645079184006, -0.10487373029905642, 0.04041528125815358, 0.1552099710452562, 0.12744683702538245, -0.0008336178155893341, -0.2227222072175235, 0.12640062895816492, -0.262147398170163, -0.1491253459159407, -0.1514704507042436, -0.030649453017642683, -0.045577724645878614, -0.3186814810169187, 0.05662437243422606, -0.026423788510580012, 0.0078276050234121, 0.07274049440405417, -0.13922550544433349, -0.00801466647139255, 0.10428432204057991, 0.10105520120407216, 0.04897490124621078, 0.17073744571444097, -0.1710296878756308, -0.17881731855425428, 0.37453168978029533, -0.04465741599440998, -0.1677066344662127, 0.13658190956537394, -0.19390272712029505, -0.18731368160212136, 0.16413092545847943, 0.2179986954871433, 0.13731487146194807, -0.16899150525310971, 0.13138742682669338, 0.03743133800771378, 0.15824651456411584, 0.057874495850492876, 0.05079541421092466, 0.1303431485277594, 0.1596019912316259, 0.0024956562787505753, 0.08718850310472441, -0.05891155620875062, -0.12910894068050469, -0.4200108886278624, -0.06862742264246476, -0.09855920002557972, 0.05386121734055766, -0.09637580100233924, -0.17641025813005812, 0.3196124488013922, 0.19831426842930786, 0.2259101857107582, 0.08784680875804249, 0.34902383270838583, 0.17648871228881577, 0.12955383457250047, 0.09036774234515978, 0.2886703806633711, 0.12440397856420184, 0.09764711582597266, -0.21350527789232368, 0.05507947937486336, 0.12436475364676287]
|
1,803.07046
|
Time-Domain Multi-Beam Selection and Its Performance Improvement for
mmWave Systems
|
Multi-beam selection is one of the crucial technologies in hybrid beamforming
systems for frequency-selective fading channels. Addressing the problem in the
frequency domain facilitates the procedure of acquiring observations for analog
beam selection. However, it is difficult to improve the quality of the
contaminated observations at low SNR. To this end, this paper uses an idea that
the significant observations are sparse in the time domain to further enhance
the quality of signals as well as the beam selection performance. By exploiting
properties of channel impulse responses and circular convolutions in the time
domain, we can reduce the size of a Toeplitz matrix in deconvolution to
generate periodic true values of coupling coefficients plus random noise
signals. An arithmetic mean of these signals yields refined observations with
minor noise effects and provides more accurate sparse multipath delay
information. As a result, only the refined observations associated with the
estimated multipath delay indices have to be taken into account for the analog
beam selection problem.
|
cs.IT math.IT
|
multibeam selection is one of the crucial technologies in hybrid beamforming systems for frequencyselective fading channels addressing the problem in the frequency domain facilitates the procedure of acquiring observations for analog beam selection however it is difficult to improve the quality of the contaminated observations at low snr to this end this paper uses an idea that the significant observations are sparse in the time domain to further enhance the quality of signals as well as the beam selection performance by exploiting properties of channel impulse responses and circular convolutions in the time domain we can reduce the size of a toeplitz matrix in deconvolution to generate periodic true values of coupling coefficients plus random noise signals an arithmetic mean of these signals yields refined observations with minor noise effects and provides more accurate sparse multipath delay information as a result only the refined observations associated with the estimated multipath delay indices have to be taken into account for the analog beam selection problem
|
[['multibeam', 'selection', 'is', 'one', 'of', 'the', 'crucial', 'technologies', 'in', 'hybrid', 'beamforming', 'systems', 'for', 'frequencyselective', 'fading', 'channels', 'addressing', 'the', 'problem', 'in', 'the', 'frequency', 'domain', 'facilitates', 'the', 'procedure', 'of', 'acquiring', 'observations', 'for', 'analog', 'beam', 'selection', 'however', 'it', 'is', 'difficult', 'to', 'improve', 'the', 'quality', 'of', 'the', 'contaminated', 'observations', 'at', 'low', 'snr', 'to', 'this', 'end', 'this', 'paper', 'uses', 'an', 'idea', 'that', 'the', 'significant', 'observations', 'are', 'sparse', 'in', 'the', 'time', 'domain', 'to', 'further', 'enhance', 'the', 'quality', 'of', 'signals', 'as', 'well', 'as', 'the', 'beam', 'selection', 'performance', 'by', 'exploiting', 'properties', 'of', 'channel', 'impulse', 'responses', 'and', 'circular', 'convolutions', 'in', 'the', 'time', 'domain', 'we', 'can', 'reduce', 'the', 'size', 'of', 'a', 'toeplitz', 'matrix', 'in', 'deconvolution', 'to', 'generate', 'periodic', 'true', 'values', 'of', 'coupling', 'coefficients', 'plus', 'random', 'noise', 'signals', 'an', 'arithmetic', 'mean', 'of', 'these', 'signals', 'yields', 'refined', 'observations', 'with', 'minor', 'noise', 'effects', 'and', 'provides', 'more', 'accurate', 'sparse', 'multipath', 'delay', 'information', 'as', 'a', 'result', 'only', 'the', 'refined', 'observations', 'associated', 'with', 'the', 'estimated', 'multipath', 'delay', 'indices', 'have', 'to', 'be', 'taken', 'into', 'account', 'for', 'the', 'analog', 'beam', 'selection', 'problem']]
|
[-0.15011618108837865, 0.05910566916122107, -0.06089788065689457, 0.04669555914591822, -0.10011873567312184, -0.14596424150712242, 0.05925265256891868, 0.4245977573658953, -0.2792569535966145, -0.28672033584699397, 0.1491040053469322, -0.23159150202281592, -0.13584448748109182, 0.17886361608632398, -0.119624016312428, 0.08013459632292791, 0.08489938144481218, -0.024085888644771243, -0.06043552979826927, -0.22277976740605948, 0.25367128036535774, 0.13216869503532241, 0.2876905513609328, -0.025006025221068186, 0.10151286726454045, 0.056911056699435705, -0.08391277902339381, -0.0247273268689197, -0.048104279762832804, 0.06427370513812071, 0.2907331254015245, 0.1393344994043795, 0.2695395488450985, -0.4160830862138693, -0.2643939679397679, 0.09406640503850834, 0.1407371598434998, 0.09044451183048872, -0.04503330078216272, -0.2916817393241927, 0.08859633646973568, -0.12895951750645665, -0.09207779550981685, -0.014553739645279853, -0.04311300859014254, 0.021650465179402268, -0.35165656544587565, 0.07483756583128635, 0.039043648808019055, 0.005603924725863446, -0.04612603436704021, -0.13872014880805025, 0.04777960592125565, 0.15790886144585362, 0.039516844816517266, 0.0175216757577401, 0.08814076650547, -0.12773602092234, -0.1021107252738325, 0.3690444166976504, -0.06156988744481989, -0.22862435159523312, 0.14490964089941927, -0.12379801362361077, -0.11631175809434796, 0.20824324233718672, 0.24402625784959373, 0.05024762402243185, -0.16518841732915196, 0.004104882439849728, 0.01303792786898046, 0.19403747699745907, 0.06801565638076082, 0.12114258730363828, 0.16459145423212293, 0.17888877549628932, 0.0908394981524907, 0.14966768723069235, -0.15552716594290203, -0.021523114936937374, -0.22826213706263465, -0.09626317428623357, -0.20680637447242967, -0.005772263181492369, -0.11280909886213854, -0.12362482770141668, 0.38888361356817414, 0.16125281607709463, 0.1855973429344708, 0.0647912502818366, 0.36604435688236775, 0.13958619110710016, 0.07420708964544735, 0.03377269772051766, 0.21205437352182344, 0.1608070799535731, 0.10950226917090576, -0.21567874310663107, 0.07626155335683285, -0.005743083130233217]
|
1,803.07047
|
Electromagnetic response of quantum Hall systems in dimensions five and
six and beyond
|
Quantum Hall (QH) states are arguably the most ubiquitous examples of
nontrivial topological order, requiring no special symmetry and elegantly
characterized by the first Chern number. Their higher dimension generalizations
are particularly interesting from both mathematical and phenomenological
perspectives, and have attracted recent attention due to a few high profile
experimental realizations. In this work, we derive from first principles the
electromagnetic response of QH systems in arbitrary number of dimensions, and
elaborate on the crucial roles played by their modified phase space density of
states under the simultaneous presence of magnetic field and Berry curvature.
We provide new mathematical results relating this phase space modification to
the non-commutativity of phase space, and show how they are manifested as a
Hall conductivity quantized by a higher Chern number. When a Fermi surface is
present, additional response currents unrelated to these Chern numbers also
appear. This unconventional response can be directly investigated through a few
minimal models with specially chosen fluxes. These models, together with more
generic 6D QH systems, can be realized in realistic 3D experimental setups like
cold atom systems through possibly entangled synthetic dimensions.
|
cond-mat.str-el physics.app-ph
|
quantum hall qh states are arguably the most ubiquitous examples of nontrivial topological order requiring no special symmetry and elegantly characterized by the first chern number their higher dimension generalizations are particularly interesting from both mathematical and phenomenological perspectives and have attracted recent attention due to a few high profile experimental realizations in this work we derive from first principles the electromagnetic response of qh systems in arbitrary number of dimensions and elaborate on the crucial roles played by their modified phase space density of states under the simultaneous presence of magnetic field and berry curvature we provide new mathematical results relating this phase space modification to the noncommutativity of phase space and show how they are manifested as a hall conductivity quantized by a higher chern number when a fermi surface is present additional response currents unrelated to these chern numbers also appear this unconventional response can be directly investigated through a few minimal models with specially chosen fluxes these models together with more generic 6d qh systems can be realized in realistic 3d experimental setups like cold atom systems through possibly entangled synthetic dimensions
|
[['quantum', 'hall', 'qh', 'states', 'are', 'arguably', 'the', 'most', 'ubiquitous', 'examples', 'of', 'nontrivial', 'topological', 'order', 'requiring', 'no', 'special', 'symmetry', 'and', 'elegantly', 'characterized', 'by', 'the', 'first', 'chern', 'number', 'their', 'higher', 'dimension', 'generalizations', 'are', 'particularly', 'interesting', 'from', 'both', 'mathematical', 'and', 'phenomenological', 'perspectives', 'and', 'have', 'attracted', 'recent', 'attention', 'due', 'to', 'a', 'few', 'high', 'profile', 'experimental', 'realizations', 'in', 'this', 'work', 'we', 'derive', 'from', 'first', 'principles', 'the', 'electromagnetic', 'response', 'of', 'qh', 'systems', 'in', 'arbitrary', 'number', 'of', 'dimensions', 'and', 'elaborate', 'on', 'the', 'crucial', 'roles', 'played', 'by', 'their', 'modified', 'phase', 'space', 'density', 'of', 'states', 'under', 'the', 'simultaneous', 'presence', 'of', 'magnetic', 'field', 'and', 'berry', 'curvature', 'we', 'provide', 'new', 'mathematical', 'results', 'relating', 'this', 'phase', 'space', 'modification', 'to', 'the', 'noncommutativity', 'of', 'phase', 'space', 'and', 'show', 'how', 'they', 'are', 'manifested', 'as', 'a', 'hall', 'conductivity', 'quantized', 'by', 'a', 'higher', 'chern', 'number', 'when', 'a', 'fermi', 'surface', 'is', 'present', 'additional', 'response', 'currents', 'unrelated', 'to', 'these', 'chern', 'numbers', 'also', 'appear', 'this', 'unconventional', 'response', 'can', 'be', 'directly', 'investigated', 'through', 'a', 'few', 'minimal', 'models', 'with', 'specially', 'chosen', 'fluxes', 'these', 'models', 'together', 'with', 'more', 'generic', '6d', 'qh', 'systems', 'can', 'be', 'realized', 'in', 'realistic', '3d', 'experimental', 'setups', 'like', 'cold', 'atom', 'systems', 'through', 'possibly', 'entangled', 'synthetic', 'dimensions']]
|
[-0.1646729732672083, 0.20894255432155062, -0.03664876254756124, 0.060712124813117725, -0.0838317733517127, -0.17826897224100927, 0.01666943515464413, 0.3472939006538601, -0.2253704353139275, -0.33391546141556516, 0.07231226299391179, -0.23853928122484194, -0.2148362333230394, 0.19721286286354586, -0.05247891506540679, 0.07680471204108588, -0.015521570787294417, -0.008722812031684894, -0.09529214628511459, -0.2380266796712393, 0.3392631162461194, 0.01697756579428691, 0.27883494073294746, 0.037046558463693126, 0.04620406719835936, -0.02386368968478975, 0.016800334866118607, 0.07760469900817805, -0.1059661037689175, 0.11873295618864578, 0.2564599682389266, -0.003716629466682833, 0.1982240505461451, -0.4857222865766255, -0.2450093139684008, 0.07297583966095361, 0.09372289016622529, 0.14206484640054706, -0.06637561310094253, -0.3232001382857561, 0.024840767167368404, -0.1765354699993466, -0.11121744705584422, -0.16305756523844697, 0.015199186228420985, -0.04272331421886901, -0.1934578006712204, 0.06052699093475327, 0.014872030203414691, 0.07792334032234965, -0.03231521785980271, -0.12579023865457142, -0.06258147469438832, 0.09471997843635324, 0.03921893235391146, -0.00046202408209923773, 0.10134216350746111, -0.1690392072965962, -0.15125563529430217, 0.3919867970705313, -0.03040332719746236, -0.20373974643367274, 0.2051711658902106, -0.15275148851064696, -0.1415734529490232, 0.13561023937560798, 0.14838578047541282, 0.10428519852043841, -0.07148490614241793, 0.07728343965768594, -0.03381515811360191, 0.12110133132501756, 0.0462605733611918, 0.11690245757207415, 0.28195337519069674, 0.10947359465588365, 0.030190533222330194, 0.15545893942270528, -0.06861041813603132, -0.09730084172840561, -0.3140028282719594, -0.16798006719534075, -0.20369705240622724, 0.07770753519043767, -0.047855155384847116, -0.11993893698954414, 0.4034312576661387, 0.13034183423345289, 0.2230347517467234, -0.016634534500534294, 0.26520793378273005, 0.13967207789368508, 0.049845035395069265, 0.028273513655789118, 0.22424471753046057, 0.15168729568431052, 0.10168219301398963, -0.204587163844256, 0.022721207090115214, 0.04531085146941565]
|
1,803.07048
|
New Physics in the Rayleigh-Jeans Tail of the CMB
|
We show that despite stringent constraints on the shape of the main part of
the CMB spectrum, there is considerable room for its modification within its
Rayleigh-Jeans (RJ) end, $\omega \ll T_{\rm CMB}$. We construct explicit New
Physics models that give an order one (or larger) increase of photon count in
the RJ tail, which can be tested by existing and upcoming experiments aiming to
detect the cosmological 21 cm emission/absorption signal. This class of models
stipulates the decay of unstable particles to dark photons, $A'$, that have a
small mass, $m_{A'} \sim 10^{-14} - 10^{-9}$ eV, non-vanishing mixing angle
$\epsilon$ with electromagnetism, and energies much smaller than $T_{\rm CMB}$.
The non-thermal number density of dark photons can be many orders of magnitude
above the number density of CMB photons, and even a small probability of $A'\to
A$ oscillations, for values of as small as $\epsilon \sim 10^{-9}$, can
significantly increase the number of RJ photons. In particular, we show that
resonant oscillations of dark photons into regular photons in the interval of
redshifts $20 < z < 1700$ can be invoked as an explanation of the recent
tentative observation of a stronger-than-expected absorption signal of 21 cm
photons. We present a model that realizes this possibility, where milli-eV mass
dark matter decays to dark photons, with a lifetime longer than the age of the
Universe.
|
hep-ph astro-ph.CO
|
we show that despite stringent constraints on the shape of the main part of the cmb spectrum there is considerable room for its modification within its rayleighjeans rj end omega ll t_rm cmb we construct explicit new physics models that give an order one or larger increase of photon count in the rj tail which can be tested by existing and upcoming experiments aiming to detect the cosmological 21 cm emissionabsorption signal this class of models stipulates the decay of unstable particles to dark photons a that have a small mass m_a sim 1014 109 ev nonvanishing mixing angle epsilon with electromagnetism and energies much smaller than t_rm cmb the nonthermal number density of dark photons can be many orders of magnitude above the number density of cmb photons and even a small probability of ato a oscillations for values of as small as epsilon sim 109 can significantly increase the number of rj photons in particular we show that resonant oscillations of dark photons into regular photons in the interval of redshifts 20 z 1700 can be invoked as an explanation of the recent tentative observation of a strongerthanexpected absorption signal of 21 cm photons we present a model that realizes this possibility where milliev mass dark matter decays to dark photons with a lifetime longer than the age of the universe
|
[['we', 'show', 'that', 'despite', 'stringent', 'constraints', 'on', 'the', 'shape', 'of', 'the', 'main', 'part', 'of', 'the', 'cmb', 'spectrum', 'there', 'is', 'considerable', 'room', 'for', 'its', 'modification', 'within', 'its', 'rayleighjeans', 'rj', 'end', 'omega', 'll', 't_rm', 'cmb', 'we', 'construct', 'explicit', 'new', 'physics', 'models', 'that', 'give', 'an', 'order', 'one', 'or', 'larger', 'increase', 'of', 'photon', 'count', 'in', 'the', 'rj', 'tail', 'which', 'can', 'be', 'tested', 'by', 'existing', 'and', 'upcoming', 'experiments', 'aiming', 'to', 'detect', 'the', 'cosmological', '21', 'cm', 'emissionabsorption', 'signal', 'this', 'class', 'of', 'models', 'stipulates', 'the', 'decay', 'of', 'unstable', 'particles', 'to', 'dark', 'photons', 'a', 'that', 'have', 'a', 'small', 'mass', 'm_a', 'sim', '1014', '109', 'ev', 'nonvanishing', 'mixing', 'angle', 'epsilon', 'with', 'electromagnetism', 'and', 'energies', 'much', 'smaller', 'than', 't_rm', 'cmb', 'the', 'nonthermal', 'number', 'density', 'of', 'dark', 'photons', 'can', 'be', 'many', 'orders', 'of', 'magnitude', 'above', 'the', 'number', 'density', 'of', 'cmb', 'photons', 'and', 'even', 'a', 'small', 'probability', 'of', 'ato', 'a', 'oscillations', 'for', 'values', 'of', 'as', 'small', 'as', 'epsilon', 'sim', '109', 'can', 'significantly', 'increase', 'the', 'number', 'of', 'rj', 'photons', 'in', 'particular', 'we', 'show', 'that', 'resonant', 'oscillations', 'of', 'dark', 'photons', 'into', 'regular', 'photons', 'in', 'the', 'interval', 'of', 'redshifts', '20', 'z', '1700', 'can', 'be', 'invoked', 'as', 'an', 'explanation', 'of', 'the', 'recent', 'tentative', 'observation', 'of', 'a', 'strongerthanexpected', 'absorption', 'signal', 'of', '21', 'cm', 'photons', 'we', 'present', 'a', 'model', 'that', 'realizes', 'this', 'possibility', 'where', 'milliev', 'mass', 'dark', 'matter', 'decays', 'to', 'dark', 'photons', 'with', 'a', 'lifetime', 'longer', 'than', 'the', 'age', 'of', 'the', 'universe']]
|
[-0.12558595413426166, 0.2250609888504374, -0.04903020328453704, 0.09419386926359777, -0.058425462673180176, -0.11232080298680562, 0.026593549610867327, 0.32008823590361485, -0.18759297147485107, -0.37508847561953046, 0.03621266456581903, -0.31413185159412665, 0.016577527532562815, 0.2046429813098718, 0.021784353670309144, -0.012240183885215005, 0.01683994984429647, 0.00869046891580081, -0.035105907404168836, -0.20826188529812367, 0.23975154898816411, 0.09523704578873447, 0.18899672050154329, 0.06332803794262187, 0.07979681743977116, -0.060498583092951454, -0.000542921099744971, -0.03279241126849245, -0.14614311385693707, 0.04511762991956865, 0.20075113571295541, 0.11319590986115365, 0.21275578050732177, -0.37473163516532143, -0.21045913612167247, 0.1980784908751435, 0.1834958690811667, 0.08001267027283179, -0.049727662697339414, -0.26694481775598944, 0.06888316787628983, -0.20980430036708045, -0.1246237597561905, -0.0008270927170299896, 0.05123768965901615, -0.029476996373401895, -0.256779554646646, 0.14247339021627511, 0.011124336870696245, -0.0065967040679379965, -0.03364084323663515, -0.13368533639604802, -0.0164749349400635, -0.004848065120982415, 0.08549554586450198, 0.04888548454136124, 0.17133309187852014, -0.14878221194055183, -0.07246117314872971, 0.39213123447167786, -0.14460829732798128, -0.06825375018094253, 0.1511134229842657, -0.1994855736336366, -0.12958874290228525, 0.19918321274041362, 0.14335997863108868, 0.09394104810506773, -0.08011565973038363, 0.07877638735082794, -0.03007416718956835, 0.26167281089358935, 0.0928252036265628, 0.08513655530909, 0.2959222120521047, 0.13786290563546924, 0.06109279808102827, 0.06448495950844273, -0.13234050659830326, 0.02076688098080139, -0.3134603422012957, -0.12815274745058852, -0.1619566149984574, 0.107617501467529, -0.14349520285155742, -0.09981894305167979, 0.3660291935601209, 0.16589058945247812, 0.25730974715194693, 0.06671847723113297, 0.3233580671484695, 0.13068486137718646, 0.06574115047811827, 0.045464334414328025, 0.31175804264100077, 0.1288446722387215, 0.05595031272277503, -0.18844235165048842, -0.015568259927536039, -0.026543019763340198]
|
1,803.07049
|
Kinematics and Dynamics of Quantum Walks in terms of Systems of
Imprimitivity
|
We build systems of imprimitivity (SI) in the context of quantum walks and
provide geometric constructions for their configuration space. We consider
three systems, an evolution of unitaries from the group SO3 on a low
dimensional de Sitter space where the walk happens on the dual of SO3, standard
quantum walk whose SI live on the orbits of stabilizer subgroups (little
groups) of semidirect products describing the symmetries of 1+1 spacetime, and
automorphisms (walks are specific automorphisms) on distant-transitive graphs
as application of the constructions.
|
math-ph math.MP
|
we build systems of imprimitivity si in the context of quantum walks and provide geometric constructions for their configuration space we consider three systems an evolution of unitaries from the group so3 on a low dimensional de sitter space where the walk happens on the dual of so3 standard quantum walk whose si live on the orbits of stabilizer subgroups little groups of semidirect products describing the symmetries of 11 spacetime and automorphisms walks are specific automorphisms on distanttransitive graphs as application of the constructions
|
[['we', 'build', 'systems', 'of', 'imprimitivity', 'si', 'in', 'the', 'context', 'of', 'quantum', 'walks', 'and', 'provide', 'geometric', 'constructions', 'for', 'their', 'configuration', 'space', 'we', 'consider', 'three', 'systems', 'an', 'evolution', 'of', 'unitaries', 'from', 'the', 'group', 'so3', 'on', 'a', 'low', 'dimensional', 'de', 'sitter', 'space', 'where', 'the', 'walk', 'happens', 'on', 'the', 'dual', 'of', 'so3', 'standard', 'quantum', 'walk', 'whose', 'si', 'live', 'on', 'the', 'orbits', 'of', 'stabilizer', 'subgroups', 'little', 'groups', 'of', 'semidirect', 'products', 'describing', 'the', 'symmetries', 'of', '11', 'spacetime', 'and', 'automorphisms', 'walks', 'are', 'specific', 'automorphisms', 'on', 'distanttransitive', 'graphs', 'as', 'application', 'of', 'the', 'constructions']]
|
[-0.17301010416122153, 0.1696729098484433, -0.05640932030621029, 0.04290837991894001, -0.047361248813103884, -0.11746846504753367, 0.009948207596261497, 0.376421867271087, -0.24453924448295897, -0.22730067283624694, 0.1676982807707862, -0.258503690894161, -0.13660917235150313, 0.19335644916143446, -0.12230806496171724, 0.01012103186388101, 0.0016203838777506636, 0.09388229270206509, -0.1280517607838625, -0.29247020611711333, 0.37540799884923864, 0.011009367013771441, 0.26048034422897864, -0.07862844806957237, 0.11891192318649874, 0.03643596727869451, -0.023356147975261723, -0.06687649114437158, -0.15235936594018268, 0.09145722438448242, 0.19671365487877102, 0.06604142822158922, 0.145958243065425, -0.41697342355646905, -0.18210302931367464, 0.1364203596908954, 0.14833760949494762, 0.1243415414036939, -0.05597386692672791, -0.36127511811043533, 0.0035373159334994853, -0.16764211339787358, -0.09066825679370336, -0.03831420663655514, 0.039456660637543314, -0.05096884453780062, -0.15389476816302963, -0.005171981468308894, 0.08171851615909309, 0.11863596748298733, -0.03265722561073268, -0.07576219313999727, -0.06163351559856286, 0.14091749686104732, -0.046725761473810835, -0.05940248210737038, 0.1811952511779964, -0.052154123983806734, -0.23052389995150624, 0.45482189523144845, -0.03147830009194357, -0.23017271643593198, 0.19572972780692258, -0.16182459993398793, -0.21559513554287454, 0.056029921486264185, 0.19183565956717802, 0.1650559676262284, -0.04319200048311835, 0.2401960314313155, -0.06211004769873051, 0.0602742878254503, 0.05616596302882369, 0.07033461249167365, 0.15285061006267955, 0.0962552563176446, 0.09675253809629274, 0.11908074827598673, 0.05252561803042356, -0.13281110864842222, -0.33298278109370066, -0.22333453627236718, -0.1388655788863876, 0.132484593916507, -0.18683189904238265, -0.2378882950509987, 0.4034843816688018, 0.057692447249878785, 0.17167534648130336, 0.07580650320908587, 0.17787518068438485, 0.02471930290699848, 0.035478666377630794, 0.080542099207551, 0.1160086298062067, 0.21917838739491777, -0.022884459523040624, -0.16525211143293528, -0.05824924252616862, 0.1843445487320423]
|
1,803.0705
|
Minimal dissipation in processes far from equilibrium
|
A central goal of thermodynamics is to identify optimal processes during
which the least amount of energy is dissipated into the environment. Generally,
even for simple systems, such as the parametric harmonic oscillator, optimal
control strategies are mathematically involved, and contain peculiar and
counter-intuitive features. We show that optimal driving protocols determined
by means of linear response theory exhibit the same step and $\delta$-peak like
structures that were previously found from solving the full optimal control
problem. However, our method is significantly less involved, since only a
minimum of a quadratic form has to be determined. In addition, our findings
suggest that optimal protocols from linear response theory are applicable far
outside their actual range of validity.
|
cond-mat.stat-mech
|
a central goal of thermodynamics is to identify optimal processes during which the least amount of energy is dissipated into the environment generally even for simple systems such as the parametric harmonic oscillator optimal control strategies are mathematically involved and contain peculiar and counterintuitive features we show that optimal driving protocols determined by means of linear response theory exhibit the same step and deltapeak like structures that were previously found from solving the full optimal control problem however our method is significantly less involved since only a minimum of a quadratic form has to be determined in addition our findings suggest that optimal protocols from linear response theory are applicable far outside their actual range of validity
|
[['a', 'central', 'goal', 'of', 'thermodynamics', 'is', 'to', 'identify', 'optimal', 'processes', 'during', 'which', 'the', 'least', 'amount', 'of', 'energy', 'is', 'dissipated', 'into', 'the', 'environment', 'generally', 'even', 'for', 'simple', 'systems', 'such', 'as', 'the', 'parametric', 'harmonic', 'oscillator', 'optimal', 'control', 'strategies', 'are', 'mathematically', 'involved', 'and', 'contain', 'peculiar', 'and', 'counterintuitive', 'features', 'we', 'show', 'that', 'optimal', 'driving', 'protocols', 'determined', 'by', 'means', 'of', 'linear', 'response', 'theory', 'exhibit', 'the', 'same', 'step', 'and', 'deltapeak', 'like', 'structures', 'that', 'were', 'previously', 'found', 'from', 'solving', 'the', 'full', 'optimal', 'control', 'problem', 'however', 'our', 'method', 'is', 'significantly', 'less', 'involved', 'since', 'only', 'a', 'minimum', 'of', 'a', 'quadratic', 'form', 'has', 'to', 'be', 'determined', 'in', 'addition', 'our', 'findings', 'suggest', 'that', 'optimal', 'protocols', 'from', 'linear', 'response', 'theory', 'are', 'applicable', 'far', 'outside', 'their', 'actual', 'range', 'of', 'validity']]
|
[-0.0923378376778251, 0.10979525609594634, -0.08216647252551892, 0.0708767829888747, -0.06941611974094158, -0.1656462295163964, 0.06778398638742411, 0.3748846827054985, -0.2806628453107471, -0.3099762046566376, 0.11453996116243717, -0.2408499904613719, -0.18323615598333123, 0.2583168444669463, -0.05037239152126205, 0.0812489551722876, 0.033929732892837405, 0.030348277093571983, -0.016048192790844757, -0.22130324274030888, 0.27499895115406847, 0.06019799409306839, 0.2881110614687045, -0.0001860372324147795, 0.09972985424837655, -0.00932457355551549, 0.002914322540163994, 0.05255561462070188, -0.1011051060541699, 0.09962444115951498, 0.2847918897795563, 0.10694369239111741, 0.3056865900149967, -0.42050918712256813, -0.23445607826877862, 0.08472967485332081, 0.14153536132031366, 0.13310722765437144, -0.02897633622503943, -0.18874378075711748, 0.09841569018217886, -0.13202383811784607, -0.12736277621732944, -0.07356245461134957, 0.01386309038493464, 0.044623588704858295, -0.2667513162566301, 0.09638623228599118, 0.05940305816137001, 0.0454872472004758, -0.08250679363472721, -0.1075447124357407, -0.023898187121296793, 0.1515238273741566, 0.008102634340588354, -0.003951232078381711, 0.17088264870481232, -0.10604428274668434, -0.105929854638381, 0.38573956999750647, -0.0014531520338585745, -0.1771832910962363, 0.18412955869068828, -0.12286177713376208, -0.10538003215582198, 0.16104197981130555, 0.1650382301881591, 0.14073914097836956, -0.1744943715265801, 0.056368121290758536, -0.014749664783430023, 0.196249788643446, 0.054950839999076136, 0.06183655881551771, 0.17317766369455773, 0.12871149513854557, 0.09916359655614783, 0.14164255159353822, 0.019643781165409293, -0.15057481346954393, -0.28704008563525146, -0.0940062750914954, -0.18618414702260086, 0.036757408349742934, -0.048278581337733634, -0.11960590281523764, 0.35677221634934664, 0.15214857853885388, 0.1756789136168539, 0.04553873083876589, 0.26847194442445904, 0.15982282828065988, 0.08102509158297291, 0.08432944181462766, 0.29996105337626916, 0.09249501595170134, 0.06636200731811233, -0.2371190749646093, 0.11493897221138717, 0.01632698041259542]
|
1,803.07051
|
Stripped-envelope supernova SN 2004dk is now interacting with
hydrogen-rich circumstellar material
|
The dominant mechanism and time scales over which stripped-envelope
supernovae (SNe) progenitor stars shed their hydrogen envelopes are uncertain.
Observations of Type Ib and Ic SNe at late phases could reveal the optical
signatures of interaction with distant circumstellar material (CSM) providing
important clues on the origin of the necessary pre-SN mass loss. We report deep
late-time optical spectroscopy of the Type Ib explosion SN 2004dk 4684 days (13
years) after discovery. Prominent intermediate-width H-alpha emission is
detected, signaling that the SN blast wave has caught up with the hydrogen-rich
CSM lost by the progenitor system. The line luminosity is the highest ever
reported for a SN at this late stage. Prominent emission features of He, Fe,
and Ca are also detected. The spectral characteristics are consistent with CSM
energized by the forward shock, and resemble the late-time spectra of the
persistently interacting Type IIn SNe 2005ip and 1988Z. We suggest that the
onset of interaction with H-rich CSM was associated with a previously reported
radio rebrightening at ~1700 days. The data indicate that the mode of pre-SN
mass loss was a relatively slow dense wind that persisted millennia before the
SN, followed by a short-lived Wolf-Rayet phase that preceded core-collapse and
created a cavity within an extended distribution of CSM. We also present new
spectra of SNe 2014C, PTF11iqb, and 2009ip, all of which also exhibit continued
interaction with extended CSM distributions.
|
astro-ph.SR astro-ph.HE
|
the dominant mechanism and time scales over which strippedenvelope supernovae sne progenitor stars shed their hydrogen envelopes are uncertain observations of type ib and ic sne at late phases could reveal the optical signatures of interaction with distant circumstellar material csm providing important clues on the origin of the necessary presn mass loss we report deep latetime optical spectroscopy of the type ib explosion sn 2004dk 4684 days 13 years after discovery prominent intermediatewidth halpha emission is detected signaling that the sn blast wave has caught up with the hydrogenrich csm lost by the progenitor system the line luminosity is the highest ever reported for a sn at this late stage prominent emission features of he fe and ca are also detected the spectral characteristics are consistent with csm energized by the forward shock and resemble the latetime spectra of the persistently interacting type iin sne 2005ip and 1988z we suggest that the onset of interaction with hrich csm was associated with a previously reported radio rebrightening at 1700 days the data indicate that the mode of presn mass loss was a relatively slow dense wind that persisted millennia before the sn followed by a shortlived wolfrayet phase that preceded corecollapse and created a cavity within an extended distribution of csm we also present new spectra of sne 2014c ptf11iqb and 2009ip all of which also exhibit continued interaction with extended csm distributions
|
[['the', 'dominant', 'mechanism', 'and', 'time', 'scales', 'over', 'which', 'strippedenvelope', 'supernovae', 'sne', 'progenitor', 'stars', 'shed', 'their', 'hydrogen', 'envelopes', 'are', 'uncertain', 'observations', 'of', 'type', 'ib', 'and', 'ic', 'sne', 'at', 'late', 'phases', 'could', 'reveal', 'the', 'optical', 'signatures', 'of', 'interaction', 'with', 'distant', 'circumstellar', 'material', 'csm', 'providing', 'important', 'clues', 'on', 'the', 'origin', 'of', 'the', 'necessary', 'presn', 'mass', 'loss', 'we', 'report', 'deep', 'latetime', 'optical', 'spectroscopy', 'of', 'the', 'type', 'ib', 'explosion', 'sn', '2004dk', '4684', 'days', '13', 'years', 'after', 'discovery', 'prominent', 'intermediatewidth', 'halpha', 'emission', 'is', 'detected', 'signaling', 'that', 'the', 'sn', 'blast', 'wave', 'has', 'caught', 'up', 'with', 'the', 'hydrogenrich', 'csm', 'lost', 'by', 'the', 'progenitor', 'system', 'the', 'line', 'luminosity', 'is', 'the', 'highest', 'ever', 'reported', 'for', 'a', 'sn', 'at', 'this', 'late', 'stage', 'prominent', 'emission', 'features', 'of', 'he', 'fe', 'and', 'ca', 'are', 'also', 'detected', 'the', 'spectral', 'characteristics', 'are', 'consistent', 'with', 'csm', 'energized', 'by', 'the', 'forward', 'shock', 'and', 'resemble', 'the', 'latetime', 'spectra', 'of', 'the', 'persistently', 'interacting', 'type', 'iin', 'sne', '2005ip', 'and', '1988z', 'we', 'suggest', 'that', 'the', 'onset', 'of', 'interaction', 'with', 'hrich', 'csm', 'was', 'associated', 'with', 'a', 'previously', 'reported', 'radio', 'rebrightening', 'at', '1700', 'days', 'the', 'data', 'indicate', 'that', 'the', 'mode', 'of', 'presn', 'mass', 'loss', 'was', 'a', 'relatively', 'slow', 'dense', 'wind', 'that', 'persisted', 'millennia', 'before', 'the', 'sn', 'followed', 'by', 'a', 'shortlived', 'wolfrayet', 'phase', 'that', 'preceded', 'corecollapse', 'and', 'created', 'a', 'cavity', 'within', 'an', 'extended', 'distribution', 'of', 'csm', 'we', 'also', 'present', 'new', 'spectra', 'of', 'sne', '2014c', 'ptf11iqb', 'and', '2009ip', 'all', 'of', 'which', 'also', 'exhibit', 'continued', 'interaction', 'with', 'extended', 'csm', 'distributions']]
|
[-0.055707880111154295, 0.1151830706086661, -0.05222052882289, 0.11023177076903862, -0.12622058132446595, -0.16856463166788735, 0.057262539500792124, 0.46540452517440606, -0.1681657918946665, -0.2620162143339885, 0.06451588041040693, -0.30823927941924795, -0.040201473553616814, 0.1617125292140027, -0.0018247448145083235, -0.10169308349602567, 0.159171922268358, -0.08052507543872142, -0.09233701179618947, -0.2726947111203995, 0.30575332321840787, 0.09780366231894606, 0.15468161638649502, -0.027023780454203068, 0.05577445783223836, -0.1300188018027131, -0.04486421875179954, -0.09826572446337227, -0.09459315399127607, 0.024076472131880643, 0.17159309082615373, 0.18045135315082134, 0.19534399444204736, -0.41637310248012815, -0.31051730509452996, 0.10314918737376816, 0.2213704659149918, 0.03118955681867223, -0.080361284936426, -0.28937471670034376, 0.038866461959420624, -0.233047726610274, -0.18939045602897311, 0.1226450922765472, 0.07524287951893147, 0.03876089725060316, -0.20239247858538373, 0.1413144083656742, 0.01625308828982364, 0.0916303795604798, -0.11128330242755854, -0.06674765809669946, -0.07793741863208888, -0.02393748963067051, 0.04873480731500955, 0.014484638673381815, 0.06426468993861911, -0.14202990832212703, 0.005250846636923158, 0.4030613770812814, -0.05191780832658345, 0.16926686879215314, 0.24867530714254826, -0.15614757119435346, -0.11714203826679671, 0.2731535606134426, 0.10543739637119118, 0.07917481637860906, -0.15062615273977983, -0.09040677269538343, 0.001023770839937838, 0.15362178254220232, 0.022469316005048437, 0.11831910426302909, 0.29773181341668786, 0.15687888584918633, -0.09960483524803843, 0.08096564897729469, -0.22448472393094124, 0.016468320638021648, -0.2720157833537087, -0.1088277408506938, -0.12844147019432997, 0.12619316336067327, -0.14635336463665038, -0.11396888430744152, 0.35830658988160047, 0.05966706974316461, 0.21451017412092088, -0.03520882748376482, 0.21663236798285024, 0.08004373687335514, 0.10303452476188701, 0.15460971222110576, 0.35273028937056017, 0.17260859465399148, 0.19953319492924493, -0.24296475885484112, 0.1427547764856015, 0.043206009153248584]
|
1,803.07052
|
The Knee and the Second Knee of the Cosmic-Ray Energy Spectrum
|
The cosmic ray flux measured by the Telescope Array Low Energy Extension
(TALE) exhibits three spectral features: the knee, the dip in the $10^{16}$ eV
decade, and the second knee. Here the spectrum has been measured for the first
time using fluorescence telescopes, which provide a calorimetric,
model-independent result. The spectrum appears to be a rigidity-dependent
cutoff sequence, where the knee is made by the hydrogen and helium portions of
the composition, the dip comes from the reduction in composition from helium to
metals, the rise to the second knee occurs due to intermediate range nuclei,
and the second knee is the iron knee.
|
astro-ph.HE
|
the cosmic ray flux measured by the telescope array low energy extension tale exhibits three spectral features the knee the dip in the 1016 ev decade and the second knee here the spectrum has been measured for the first time using fluorescence telescopes which provide a calorimetric modelindependent result the spectrum appears to be a rigiditydependent cutoff sequence where the knee is made by the hydrogen and helium portions of the composition the dip comes from the reduction in composition from helium to metals the rise to the second knee occurs due to intermediate range nuclei and the second knee is the iron knee
|
[['the', 'cosmic', 'ray', 'flux', 'measured', 'by', 'the', 'telescope', 'array', 'low', 'energy', 'extension', 'tale', 'exhibits', 'three', 'spectral', 'features', 'the', 'knee', 'the', 'dip', 'in', 'the', '1016', 'ev', 'decade', 'and', 'the', 'second', 'knee', 'here', 'the', 'spectrum', 'has', 'been', 'measured', 'for', 'the', 'first', 'time', 'using', 'fluorescence', 'telescopes', 'which', 'provide', 'a', 'calorimetric', 'modelindependent', 'result', 'the', 'spectrum', 'appears', 'to', 'be', 'a', 'rigiditydependent', 'cutoff', 'sequence', 'where', 'the', 'knee', 'is', 'made', 'by', 'the', 'hydrogen', 'and', 'helium', 'portions', 'of', 'the', 'composition', 'the', 'dip', 'comes', 'from', 'the', 'reduction', 'in', 'composition', 'from', 'helium', 'to', 'metals', 'the', 'rise', 'to', 'the', 'second', 'knee', 'occurs', 'due', 'to', 'intermediate', 'range', 'nuclei', 'and', 'the', 'second', 'knee', 'is', 'the', 'iron', 'knee']]
|
[-0.03981796886700277, 0.1894139936641575, -0.06546596590823565, 0.10932817880753785, -0.01919717354870115, -0.04377657926390664, 0.0162660555137196, 0.3603987702472995, -0.2524424412359412, -0.40201703616632867, 0.019925648998021364, -0.33355319490118956, -0.018567370277686186, 0.1712854382214853, -0.006324755164454333, -0.03104711778332085, 0.04380778368347539, 0.0011013428069977986, -0.05422672592640783, -0.13067371518655607, 0.2886718751486534, 0.19350105564808473, 0.25863616465358064, 0.07884894873803625, 0.08040435989208233, -0.10433474196738993, 0.0020984830872084084, -0.08035685143505152, -0.05954002340933165, 0.0928408889113388, 0.23568550072601424, 0.05396250793665576, 0.1760815553761159, -0.33351272174443763, -0.24663408835812545, 0.12374752827543908, 0.16784489830920044, 0.013997139891636414, -0.07346908772552314, -0.23634943242135564, 0.06976733956700908, -0.16491001459675877, -0.15057233679376972, 0.06957348945252306, -0.05492407337834056, 0.007269451855860937, -0.1958976486035121, 0.10012068402451965, 0.04904992378746661, 0.04724358579215522, -0.10379935408015556, -0.11753535705009618, 0.015545216258033179, 0.1340725037197654, 0.08175872956277229, 0.04505478175661455, 0.1609777438749846, -0.060865336760448724, -0.031465810629575014, 0.42348561274747437, -0.11219986717556961, 0.04995785478072671, 0.11917584992569083, -0.22386615157413942, -0.1310642747960698, 0.23855601485746986, 0.08040130224365455, 0.08391282572119962, -0.1575215846264305, 0.08501514372535614, 0.060886231860002644, 0.21789662351007932, 0.09092339557425405, -0.02641606321916557, 0.21821868277262324, 0.20004201968102, 0.06796178541396959, 0.07157859458395531, -0.2217008375401537, 0.02634573698742315, -0.26347474476250893, -0.12289086988983819, -0.17106706083107454, 0.05927275685378565, -0.034306784706271944, -0.16565058693567364, 0.45108742269579893, 0.07284983637957619, 0.2673911934208053, 0.00858548200407173, 0.31639255459706944, 0.12452803084698434, 0.07148869733702248, 0.007497074816805812, 0.3291279540146486, 0.12654485133064625, 0.1814565991785807, -0.22153908200198202, 0.06544485487616979, 0.06128381135372015]
|
1,803.07053
|
Attack-Resilient H2, H-infinity, and L1 State Estimator
|
This paper considers the secure state estimation problem for noisy systems in
the presence of sparse sensor integrity attacks. We show a fundamental
limitation: that is, 2r-detectability is necessary for achieving bounded
estimation errors, where r is the number of attacks. This condition is weaker
than the 2r-observability condition typically assumed in the literature.
Conversely, we propose a real-time state estimator that achieves the
fundamental limitation. The proposed state estimator is inspired by robust
control and FDI: that is, it consists of local Luenberger estimators, local
residual detectors, and a global fusion process. We show its performance
guarantees for H2, H-infinity, and L1 systems. Finally, numerical examples show
that it has relatively low estimation errors among existing algorithms and
average computation time for systems with a sufficiently small number of
compromised sensors.
|
math.OC
|
this paper considers the secure state estimation problem for noisy systems in the presence of sparse sensor integrity attacks we show a fundamental limitation that is 2rdetectability is necessary for achieving bounded estimation errors where r is the number of attacks this condition is weaker than the 2robservability condition typically assumed in the literature conversely we propose a realtime state estimator that achieves the fundamental limitation the proposed state estimator is inspired by robust control and fdi that is it consists of local luenberger estimators local residual detectors and a global fusion process we show its performance guarantees for h2 hinfinity and l1 systems finally numerical examples show that it has relatively low estimation errors among existing algorithms and average computation time for systems with a sufficiently small number of compromised sensors
|
[['this', 'paper', 'considers', 'the', 'secure', 'state', 'estimation', 'problem', 'for', 'noisy', 'systems', 'in', 'the', 'presence', 'of', 'sparse', 'sensor', 'integrity', 'attacks', 'we', 'show', 'a', 'fundamental', 'limitation', 'that', 'is', '2rdetectability', 'is', 'necessary', 'for', 'achieving', 'bounded', 'estimation', 'errors', 'where', 'r', 'is', 'the', 'number', 'of', 'attacks', 'this', 'condition', 'is', 'weaker', 'than', 'the', '2robservability', 'condition', 'typically', 'assumed', 'in', 'the', 'literature', 'conversely', 'we', 'propose', 'a', 'realtime', 'state', 'estimator', 'that', 'achieves', 'the', 'fundamental', 'limitation', 'the', 'proposed', 'state', 'estimator', 'is', 'inspired', 'by', 'robust', 'control', 'and', 'fdi', 'that', 'is', 'it', 'consists', 'of', 'local', 'luenberger', 'estimators', 'local', 'residual', 'detectors', 'and', 'a', 'global', 'fusion', 'process', 'we', 'show', 'its', 'performance', 'guarantees', 'for', 'h2', 'hinfinity', 'and', 'l1', 'systems', 'finally', 'numerical', 'examples', 'show', 'that', 'it', 'has', 'relatively', 'low', 'estimation', 'errors', 'among', 'existing', 'algorithms', 'and', 'average', 'computation', 'time', 'for', 'systems', 'with', 'a', 'sufficiently', 'small', 'number', 'of', 'compromised', 'sensors']]
|
[-0.18550812768964814, 0.029042639060375783, -0.043413648525109656, 0.04405327739801018, -0.021993487811862278, -0.2020650252735672, 0.047493035793125346, 0.3751550349406898, -0.25670677390522684, -0.2922294042359751, 0.17476518683744452, -0.23939376506023108, -0.1798502155373661, 0.20278797148941802, -0.1782577127627939, 0.1280641070992435, 0.10315549676127445, 0.03755623264094958, -0.0541376595170452, -0.2810910883279016, 0.28466375249151427, 0.06089359070532597, 0.3184639487648383, 0.011759904105789386, 0.14453753181733192, 0.008513918304994988, -0.0013592933483708364, 0.02440086925545564, -0.0763582009981082, 0.12443202803394972, 0.26238669796058767, 0.16420961876328175, 0.3592130697403963, -0.37742738946600674, -0.21521003427557073, 0.149426408069065, 0.12901658678893, 0.1280864724674477, -0.057701413944148676, -0.26694648067037074, 0.16777026771854323, -0.1783196158778782, -0.05777488700651492, -0.09095140725660783, 0.0066818663563865885, -0.0047441151852791125, -0.3523466549455546, 0.10425388182585056, 0.07203198709131146, 0.04481908297166228, -0.04463706976966932, -0.09032031461560669, 0.0335214470871366, 0.09708533502685336, 0.015649130119933175, -0.01285066637568749, 0.16598847848855747, -0.12585648666494167, -0.08000225921591314, 0.333789003160424, -0.020742561053059314, -0.22026737539026026, 0.17858263320432832, -0.06111236496362835, -0.14101607602519484, 0.11719881890055078, 0.16399310443263787, 0.10523992819138445, -0.1334633584993963, 0.08089275521320255, -0.03860677361058501, 0.2079716827505483, -0.005027844898331051, 0.08268326131913524, 0.10773519504134758, 0.19822162391904455, 0.19979245182341682, 0.13099423301531576, -0.1187868909270037, -0.056864568648430015, -0.29052999522536993, -0.10672057181095275, -0.21332067186371065, -0.027994108112314, -0.07091146257589571, -0.1349550813006667, 0.3364532392615309, 0.19568382245846666, 0.15344269669686372, 0.10066908453770268, 0.4058319094232642, 0.1012258863578049, 0.01557768815770172, 0.13430726864160253, 0.24624266393769245, 0.11189885388235919, 0.05850464585573018, -0.1938767416187777, 0.14955043617922525, 0.026256714118622206]
|
1,803.07054
|
Optimal link prediction with matrix logistic regression
|
We consider the problem of link prediction, based on partial observation of a
large network, and on side information associated to its vertices. The
generative model is formulated as a matrix logistic regression. The performance
of the model is analysed in a high-dimensional regime under a structural
assumption. The minimax rate for the Frobenius-norm risk is established and a
combinatorial estimator based on the penalised maximum likelihood approach is
shown to achieve it. Furthermore, it is shown that this rate cannot be attained
by any (randomised) algorithm computable in polynomial time under a
computational complexity assumption.
|
math.ST stat.ML stat.TH
|
we consider the problem of link prediction based on partial observation of a large network and on side information associated to its vertices the generative model is formulated as a matrix logistic regression the performance of the model is analysed in a highdimensional regime under a structural assumption the minimax rate for the frobeniusnorm risk is established and a combinatorial estimator based on the penalised maximum likelihood approach is shown to achieve it furthermore it is shown that this rate cannot be attained by any randomised algorithm computable in polynomial time under a computational complexity assumption
|
[['we', 'consider', 'the', 'problem', 'of', 'link', 'prediction', 'based', 'on', 'partial', 'observation', 'of', 'a', 'large', 'network', 'and', 'on', 'side', 'information', 'associated', 'to', 'its', 'vertices', 'the', 'generative', 'model', 'is', 'formulated', 'as', 'a', 'matrix', 'logistic', 'regression', 'the', 'performance', 'of', 'the', 'model', 'is', 'analysed', 'in', 'a', 'highdimensional', 'regime', 'under', 'a', 'structural', 'assumption', 'the', 'minimax', 'rate', 'for', 'the', 'frobeniusnorm', 'risk', 'is', 'established', 'and', 'a', 'combinatorial', 'estimator', 'based', 'on', 'the', 'penalised', 'maximum', 'likelihood', 'approach', 'is', 'shown', 'to', 'achieve', 'it', 'furthermore', 'it', 'is', 'shown', 'that', 'this', 'rate', 'can', 'not', 'be', 'attained', 'by', 'any', 'randomised', 'algorithm', 'computable', 'in', 'polynomial', 'time', 'under', 'a', 'computational', 'complexity', 'assumption']]
|
[-0.0903235668935765, -0.007092583166032108, -0.1224008628584867, 0.10518523798199352, -0.07108748037867325, -0.18172078336272196, 0.09608909445478744, 0.3849985868737255, -0.31148387050044907, -0.2542236575031096, 0.16563470558666615, -0.2097980192785641, -0.20721974390914144, 0.19569683213209368, -0.13567760429277861, 0.1185577108336315, 0.08407812918891612, 0.09854429998175845, -0.04079290288108936, -0.31068433975061577, 0.2768804636056602, 0.07978643640184525, 0.31774755394729526, 0.04085156192268562, 0.16346134865637293, -0.0009056285033290534, -0.0018337518648849321, 0.053348432140204016, -0.12195227286556662, 0.1050171116378984, 0.23993730994383083, 0.19324848587149465, 0.3369721343222353, -0.37188927508583386, -0.21747456220237865, 0.144229470701773, 0.08114475282941244, 0.07239462569183142, -0.003759077384098212, -0.24462064996976213, 0.08974011263872507, -0.13443162549555915, -0.04409169692296496, -0.038688249629202115, -0.050294001173880915, -0.030483132785128562, -0.37966808245142863, 0.08440589992636718, 0.06098793941962811, 0.02814673891377434, -0.012791881156538027, -0.1079491686229546, 0.019063610089078697, 0.03591305662196168, 0.05701030731157966, 0.03999308049174736, 0.08695523524968933, -0.12092984118018799, -0.11896867554193151, 0.3434385998827434, -0.07012854396250368, -0.2562016142681049, 0.15134673615792746, -0.08460545280141775, -0.14253207783877236, 0.1296987503901431, 0.2018673375210504, 0.11187828386912949, -0.17605691437235044, 0.10271063696511436, -0.09092075052219875, 0.19114171928658927, 0.028167773345389318, -0.009064318386588208, 0.1077910323132828, 0.22764229138391381, 0.11804314508803726, 0.1533765949527301, -0.07840321714492976, -0.09379095539508253, -0.24125396880830072, -0.12299973642772793, -0.25733638471280484, 0.014663368768506376, -0.13881103769688838, -0.15952027675674116, 0.35543994223410935, 0.1319103198769243, 0.19925872041104534, 0.1497824764282433, 0.2939485537989987, 0.14894372936621422, 0.028759046462508514, 0.10245091887190938, 0.21061344745271293, 0.12369894798240173, 0.016479058474417507, -0.20674111799231357, 0.19636814061494678, 0.096020667765712]
|
1,803.07055
|
Simple random search provides a competitive approach to reinforcement
learning
|
A common belief in model-free reinforcement learning is that methods based on
random search in the parameter space of policies exhibit significantly worse
sample complexity than those that explore the space of actions. We dispel such
beliefs by introducing a random search method for training static, linear
policies for continuous control problems, matching state-of-the-art sample
efficiency on the benchmark MuJoCo locomotion tasks. Our method also finds a
nearly optimal controller for a challenging instance of the Linear Quadratic
Regulator, a classical problem in control theory, when the dynamics are not
known. Computationally, our random search algorithm is at least 15 times more
efficient than the fastest competing model-free methods on these benchmarks. We
take advantage of this computational efficiency to evaluate the performance of
our method over hundreds of random seeds and many different hyperparameter
configurations for each benchmark task. Our simulations highlight a high
variability in performance in these benchmark tasks, suggesting that commonly
used estimations of sample efficiency do not adequately evaluate the
performance of RL algorithms.
|
cs.LG cs.AI math.OC stat.ML
|
a common belief in modelfree reinforcement learning is that methods based on random search in the parameter space of policies exhibit significantly worse sample complexity than those that explore the space of actions we dispel such beliefs by introducing a random search method for training static linear policies for continuous control problems matching stateoftheart sample efficiency on the benchmark mujoco locomotion tasks our method also finds a nearly optimal controller for a challenging instance of the linear quadratic regulator a classical problem in control theory when the dynamics are not known computationally our random search algorithm is at least 15 times more efficient than the fastest competing modelfree methods on these benchmarks we take advantage of this computational efficiency to evaluate the performance of our method over hundreds of random seeds and many different hyperparameter configurations for each benchmark task our simulations highlight a high variability in performance in these benchmark tasks suggesting that commonly used estimations of sample efficiency do not adequately evaluate the performance of rl algorithms
|
[['a', 'common', 'belief', 'in', 'modelfree', 'reinforcement', 'learning', 'is', 'that', 'methods', 'based', 'on', 'random', 'search', 'in', 'the', 'parameter', 'space', 'of', 'policies', 'exhibit', 'significantly', 'worse', 'sample', 'complexity', 'than', 'those', 'that', 'explore', 'the', 'space', 'of', 'actions', 'we', 'dispel', 'such', 'beliefs', 'by', 'introducing', 'a', 'random', 'search', 'method', 'for', 'training', 'static', 'linear', 'policies', 'for', 'continuous', 'control', 'problems', 'matching', 'stateoftheart', 'sample', 'efficiency', 'on', 'the', 'benchmark', 'mujoco', 'locomotion', 'tasks', 'our', 'method', 'also', 'finds', 'a', 'nearly', 'optimal', 'controller', 'for', 'a', 'challenging', 'instance', 'of', 'the', 'linear', 'quadratic', 'regulator', 'a', 'classical', 'problem', 'in', 'control', 'theory', 'when', 'the', 'dynamics', 'are', 'not', 'known', 'computationally', 'our', 'random', 'search', 'algorithm', 'is', 'at', 'least', '15', 'times', 'more', 'efficient', 'than', 'the', 'fastest', 'competing', 'modelfree', 'methods', 'on', 'these', 'benchmarks', 'we', 'take', 'advantage', 'of', 'this', 'computational', 'efficiency', 'to', 'evaluate', 'the', 'performance', 'of', 'our', 'method', 'over', 'hundreds', 'of', 'random', 'seeds', 'and', 'many', 'different', 'hyperparameter', 'configurations', 'for', 'each', 'benchmark', 'task', 'our', 'simulations', 'highlight', 'a', 'high', 'variability', 'in', 'performance', 'in', 'these', 'benchmark', 'tasks', 'suggesting', 'that', 'commonly', 'used', 'estimations', 'of', 'sample', 'efficiency', 'do', 'not', 'adequately', 'evaluate', 'the', 'performance', 'of', 'rl', 'algorithms']]
|
[-0.055060612327782935, 0.011466637824127483, -0.07878646614669255, 0.08178462151826509, -0.09693922322021643, -0.15590798037440776, 0.09360293384032467, 0.45222205087851136, -0.23843850987858672, -0.36714188008398346, 0.09402940101844408, -0.2254362505510692, -0.16296392117458885, 0.283379806868991, -0.09357679562819515, 0.1135272074479764, 0.11574566274600313, 0.012642650024623737, -0.07115108462342629, -0.32960831030057025, 0.24166335543678225, 0.02818568257240237, 0.32474284923288244, -0.042879715986197164, 0.11279509761012517, -0.02205844293486261, -0.004993816274190707, 0.02225252559247355, -0.06661298369485767, 0.11245303278576758, 0.3064791422403423, 0.18049861053996802, 0.3763852171329837, -0.3661577826271198, -0.22494502989547713, 0.1333254601898708, 0.14525241628785193, 0.08130898304316683, -0.041103541907270925, -0.25307356412439835, 0.09666047284287296, -0.1395066757025142, -0.020898636287910388, -0.12908224714782154, -0.02742448296899406, 0.004811999414731974, -0.2998629966447648, 0.030563288826885297, 0.053303148013335716, 0.04449868672003848, -0.06107126176495039, -0.15939213514752334, 0.05331263617342393, 0.10515824694426858, 0.032197214684383, 0.026538393330710702, 0.16609581046704666, -0.15595279091797953, -0.2373120629823816, 0.3795368310777724, -0.03998112479674619, -0.2201679477195349, 0.23070633753213876, -0.06809988323896682, -0.15465944652726665, 0.1344753878574113, 0.2591740420011021, 0.21505235870969455, -0.1339942070772801, 0.03449134259951747, -0.041592948919867534, 0.18480547036446587, 0.004552571770987204, -0.00032312275232890475, 0.11935822126598886, 0.2540991356990372, 0.11379539250697908, 0.1179053729163075, -0.05425542422856849, -0.15766262191419417, -0.20870344530234455, -0.08699478876581361, -0.17633977047713287, -0.019718366834030557, -0.17516903455509356, -0.15397362017001098, 0.3734972559841427, 0.2525001199218202, 0.16482243503129781, 0.13457363314882537, 0.35736824294342795, 0.05417253353947101, 0.07413727353112055, 0.12940418332596115, 0.2309654077732682, -0.005532353657667012, 0.07085038304326163, -0.23793517761538632, 0.1036394948274801, 0.03422034424095905]
|
1,803.07056
|
Non-evaporable getter coating chambers for extreme high vacuum
|
Techniques for NEG coating a large diameter chamber are presented along with
vacuum measurements in the chamber using several pumping configurations, with
base pressure as low as 1.56x10^-12 Torr (N2 equivalent) with only a NEG
coating and small ion pump. We then describe modifications to the NEG coating
process to coat complex geometry chambers for ultra-cold atom trap experiments.
Surface analysis of NEG coated samples are used to measure composition and
morphology of the thin films. Finally, pressure measurements are compared for
two NEG coated polarized electron source chambers: the 130 kV polarized
electron source at Jefferson Lab and the upgraded 350 kV polarized 2 electron
source, both of which are approaching or within the extreme high vacuum (XHV)
range, defined as P<7.5x10^-13 Torr.
|
physics.acc-ph
|
techniques for neg coating a large diameter chamber are presented along with vacuum measurements in the chamber using several pumping configurations with base pressure as low as 156x1012 torr n2 equivalent with only a neg coating and small ion pump we then describe modifications to the neg coating process to coat complex geometry chambers for ultracold atom trap experiments surface analysis of neg coated samples are used to measure composition and morphology of the thin films finally pressure measurements are compared for two neg coated polarized electron source chambers the 130 kv polarized electron source at jefferson lab and the upgraded 350 kv polarized 2 electron source both of which are approaching or within the extreme high vacuum xhv range defined as p75x1013 torr
|
[['techniques', 'for', 'neg', 'coating', 'a', 'large', 'diameter', 'chamber', 'are', 'presented', 'along', 'with', 'vacuum', 'measurements', 'in', 'the', 'chamber', 'using', 'several', 'pumping', 'configurations', 'with', 'base', 'pressure', 'as', 'low', 'as', '156x1012', 'torr', 'n2', 'equivalent', 'with', 'only', 'a', 'neg', 'coating', 'and', 'small', 'ion', 'pump', 'we', 'then', 'describe', 'modifications', 'to', 'the', 'neg', 'coating', 'process', 'to', 'coat', 'complex', 'geometry', 'chambers', 'for', 'ultracold', 'atom', 'trap', 'experiments', 'surface', 'analysis', 'of', 'neg', 'coated', 'samples', 'are', 'used', 'to', 'measure', 'composition', 'and', 'morphology', 'of', 'the', 'thin', 'films', 'finally', 'pressure', 'measurements', 'are', 'compared', 'for', 'two', 'neg', 'coated', 'polarized', 'electron', 'source', 'chambers', 'the', '130', 'kv', 'polarized', 'electron', 'source', 'at', 'jefferson', 'lab', 'and', 'the', 'upgraded', '350', 'kv', 'polarized', '2', 'electron', 'source', 'both', 'of', 'which', 'are', 'approaching', 'or', 'within', 'the', 'extreme', 'high', 'vacuum', 'xhv', 'range', 'defined', 'as', 'p75x1013', 'torr']]
|
[-0.006109716713212985, 0.2171259449817979, -0.037971487016732655, -0.030584125038188154, 0.007627501666222599, -0.21235437344082378, -0.006153318811639035, 0.4675758834158586, -0.20374970003377554, -0.3297308790035669, 0.09232575190830822, -0.32686732000525087, 0.07677574042992835, 0.2155677236304888, -0.02266510779592247, 0.06990613703075257, -0.009116598928331837, -0.08913456595864547, -0.07738173865878661, -0.18775943468117023, 0.2540423205922827, 0.11252232043703725, 0.2989425706207629, 0.10284620837870338, 0.16633146533873394, -0.02464859501828155, 0.03425801724881224, 0.0089927745794431, -0.12043130426659934, 0.03477599396762892, 0.27658948843936965, -0.0009347646735793303, 0.1443843978249337, -0.4800831078251531, -0.17840596552445623, 0.02336758046895881, 0.059211869233418715, 0.04602463425941427, -0.09940340805968101, -0.2214759681979964, 0.07738747170040083, -0.1669005857634335, -0.1778770956280064, -0.0068560465958646755, 0.0014837358901200217, 0.05576137108112539, -0.26047425748528297, -0.008227019780267353, 0.006982165030857994, 0.09377402355817478, -0.09832886970324889, -0.17495643822206877, -0.005375717755037645, 0.01993428262466303, 0.004338777885524063, 0.10078556034406108, 0.2940013536467594, -0.1122631465261879, -0.03955615954935428, 0.3086948338742099, -0.11911219066684327, -0.15955606107561549, 0.20126514085991817, -0.21640164014971852, 0.01663340705115933, 0.20125784187708512, 0.1483989568688899, 0.13761497931631883, -0.13051094717061348, 0.023898311875989536, -0.039008821241465236, 0.20145523401371357, 0.22826995320949117, -0.014714643332245182, 0.19449919103529334, 0.17212641944970228, 0.02293831333979841, 0.13752853810560625, -0.17933074540404742, 0.043483695169248854, -0.28893643192762186, -0.20591776778782941, -0.12377638638227377, 0.05314043465874751, -0.030363426581895833, -0.14031150791994182, 0.30548443715280493, 0.0477387038875402, 0.1508385121960901, -0.05023074015293825, 0.3114778701108226, -0.004150016969339229, 0.0811572500152421, -0.021162204151926947, 0.21110996997757422, 0.19461550223564128, 0.1279980525864367, -0.20935480550512642, 0.03482048090307758, -0.03629103721665942]
|
1,803.07057
|
A radial velocity survey of the Carina Nebula's O-type stars
|
We have obtained multi-epoch observations of 31 O-type stars in the Carina
Nebula using the CHIRON spectrograph on the CTIO/SMARTS 1.5-m telescope. We
measure their radial velocities to 1--2 km s$^{-1}$ precision and present new
or updated orbital solutions for the binary systems HD 92607, HD 93576, HDE
303312, and HDE 305536. We also compile radial velocities from the literature
for 32 additional O-type and evolved massive stars in the region. The combined
data set shows a mean heliocentric radial velocity of 0.6 km s$^{-1}$. We
calculate a velocity dispersion of $\le9.1$ km s$^{-1}$, consistent with an
unbound, substructured OB association. The Tr 14 cluster shows a marginally
significant 5 km s$^{-1}$ radial velocity offset from its neighbor Tr 16, but
there are otherwise no correlations between stellar position and velocity. The
O-type stars in Cr 228 and the South Pillars region have a lower velocity
dispersion than the region as a whole, supporting a model of distributed
massive-star formation rather than migration from the central clusters. We
compare our stellar velocities to the Carina Nebula's molecular gas and find
that Tr 14 shows a close kinematic association with the Northern Cloud. In
contrast, Tr 16 has accelerated the Southern Cloud by 10--15 km s$^{-1}$,
possibly triggering further massive-star formation. The expansion of the
surrounding H II region is not symmetric about the O-type stars in radial
velocity space, indicating that the ionized gas is constrained by denser
material on the far side.
|
astro-ph.SR astro-ph.GA
|
we have obtained multiepoch observations of 31 otype stars in the carina nebula using the chiron spectrograph on the ctiosmarts 15m telescope we measure their radial velocities to 12 km s1 precision and present new or updated orbital solutions for the binary systems hd 92607 hd 93576 hde 303312 and hde 305536 we also compile radial velocities from the literature for 32 additional otype and evolved massive stars in the region the combined data set shows a mean heliocentric radial velocity of 06 km s1 we calculate a velocity dispersion of le91 km s1 consistent with an unbound substructured ob association the tr 14 cluster shows a marginally significant 5 km s1 radial velocity offset from its neighbor tr 16 but there are otherwise no correlations between stellar position and velocity the otype stars in cr 228 and the south pillars region have a lower velocity dispersion than the region as a whole supporting a model of distributed massivestar formation rather than migration from the central clusters we compare our stellar velocities to the carina nebulas molecular gas and find that tr 14 shows a close kinematic association with the northern cloud in contrast tr 16 has accelerated the southern cloud by 1015 km s1 possibly triggering further massivestar formation the expansion of the surrounding h ii region is not symmetric about the otype stars in radial velocity space indicating that the ionized gas is constrained by denser material on the far side
|
[['we', 'have', 'obtained', 'multiepoch', 'observations', 'of', '31', 'otype', 'stars', 'in', 'the', 'carina', 'nebula', 'using', 'the', 'chiron', 'spectrograph', 'on', 'the', 'ctiosmarts', '15m', 'telescope', 'we', 'measure', 'their', 'radial', 'velocities', 'to', '12', 'km', 's1', 'precision', 'and', 'present', 'new', 'or', 'updated', 'orbital', 'solutions', 'for', 'the', 'binary', 'systems', 'hd', '92607', 'hd', '93576', 'hde', '303312', 'and', 'hde', '305536', 'we', 'also', 'compile', 'radial', 'velocities', 'from', 'the', 'literature', 'for', '32', 'additional', 'otype', 'and', 'evolved', 'massive', 'stars', 'in', 'the', 'region', 'the', 'combined', 'data', 'set', 'shows', 'a', 'mean', 'heliocentric', 'radial', 'velocity', 'of', '06', 'km', 's1', 'we', 'calculate', 'a', 'velocity', 'dispersion', 'of', 'le91', 'km', 's1', 'consistent', 'with', 'an', 'unbound', 'substructured', 'ob', 'association', 'the', 'tr', '14', 'cluster', 'shows', 'a', 'marginally', 'significant', '5', 'km', 's1', 'radial', 'velocity', 'offset', 'from', 'its', 'neighbor', 'tr', '16', 'but', 'there', 'are', 'otherwise', 'no', 'correlations', 'between', 'stellar', 'position', 'and', 'velocity', 'the', 'otype', 'stars', 'in', 'cr', '228', 'and', 'the', 'south', 'pillars', 'region', 'have', 'a', 'lower', 'velocity', 'dispersion', 'than', 'the', 'region', 'as', 'a', 'whole', 'supporting', 'a', 'model', 'of', 'distributed', 'massivestar', 'formation', 'rather', 'than', 'migration', 'from', 'the', 'central', 'clusters', 'we', 'compare', 'our', 'stellar', 'velocities', 'to', 'the', 'carina', 'nebulas', 'molecular', 'gas', 'and', 'find', 'that', 'tr', '14', 'shows', 'a', 'close', 'kinematic', 'association', 'with', 'the', 'northern', 'cloud', 'in', 'contrast', 'tr', '16', 'has', 'accelerated', 'the', 'southern', 'cloud', 'by', '1015', 'km', 's1', 'possibly', 'triggering', 'further', 'massivestar', 'formation', 'the', 'expansion', 'of', 'the', 'surrounding', 'h', 'ii', 'region', 'is', 'not', 'symmetric', 'about', 'the', 'otype', 'stars', 'in', 'radial', 'velocity', 'space', 'indicating', 'that', 'the', 'ionized', 'gas', 'is', 'constrained', 'by', 'denser', 'material', 'on', 'the', 'far', 'side']]
|
[-0.11705736671828766, 0.11808952555103676, -0.0603015849086996, 0.05251661082436213, -0.09368490824425015, -0.07238487563166424, 0.06775743286457978, 0.42657131033346934, -0.14111191492152064, -0.318698487197589, 0.056734139324721544, -0.2861223921938917, 0.03181465853009561, 0.18499410641379654, -0.016611741807315686, -0.08018477314700638, 0.12440348699681085, 0.01767173907210847, -0.05890116760968974, -0.2134618616091604, 0.26470804388660296, 0.06245487485559825, 0.13426497021881753, -0.04947902224693807, 0.0670416387344149, -0.15090081054607735, -0.06790220380678554, -0.0234970002399196, -0.1858653842446227, 0.08072284534852364, 0.1560466995085159, 0.12068154412407835, 0.22106319468687563, -0.3101332677418695, -0.21262186549470893, 0.01162720563089741, 0.2597354027548288, -0.0005742845520721513, -0.02964104116591527, -0.31126966580460946, 0.059995943435835614, -0.22882421407261627, -0.23364462239370376, 0.10634705949425032, 0.08448989380140272, 0.01738696895635632, -0.2025112619529627, 0.17921602765884262, -0.03304895633800315, 0.17819505131523664, -0.15990164542146137, -0.15767201118586005, -0.0911935179982483, 0.04406016065246042, -0.009252465645559602, 0.12155222964566983, 0.1580975646619732, -0.10090131459937689, 0.019432155338620784, 0.4061144979341942, -0.09631045050530189, -0.012011336663565715, 0.24491837887365386, -0.2403496551648283, -0.1530826692019409, 0.17732524812933714, 0.15687033135694364, 0.11169369587236468, -0.16284837328609736, -0.012290747438561359, -0.06818269243945188, 0.21802967438667997, 0.07398853297325775, 0.05031143911838328, 0.29770175657360304, 0.05963254144254822, 0.06470700824621502, 0.06537139311456318, -0.3307321298957466, -0.0909726978191605, -0.21201857452208916, -0.12710325528394056, -0.07961824951994725, 0.03820891293043813, -0.1736863352307715, -0.075492977483605, 0.2833539178700601, 0.09268188770786329, 0.21147797493256254, 0.017080903989008526, 0.2877401191107303, 0.053495084962324815, 0.12814837988385805, 0.2330423640713346, 0.31856894775630296, 0.1998202760386899, 0.14836112464222462, -0.24597734441499405, 0.05466437162714032, 0.0014262902697141306]
|
1,803.07058
|
Overshooting calibration and age determination from evolved binary
system
|
We evaluated the bias and variability on the fitted age and convective core
overshooting parameter for evolved binary stars accounting for observational
and internal uncertainties. We considered a binary system composed of a 2.50
$M_{\sun}$ primary star coupled with a 2.38 $M_{\sun}$ secondary in three
evolutionary stages (primary at the end of the central helium burning; at the
bottom of the RGB; and in the helium core burning). The simulations have been
carried out for two values of accuracy on the mass determination (1% and 0.1%).
We found that the fitted age and overshooting efficiency are always biased
towards low values. The underestimation is relevant for a primary in the
central helium burning stage, reaching -8.5% in age and -0.04 (-25% relative
error) in the overshooting parameter $\beta$. In the other scenarios, an
undervaluation of the age by about 4% occurs. A large variability in the fitted
values between simulations was found: for an individual system calibration, the
value of $\beta$ can vary from 0.0 to 0.26. For an error of 0.1% on the masses
the global variability is suppressed by a factor of two. We accounted for a
systematic offset in the effective temperature of the stars by $\pm 150$ K. For
a mass error of 1% $\beta$ is largely biased towards the edges of the explored
range, while for the lower mass uncertainty it is basically unconstrained from
0.0 to 0.2. We evaluated the possibility of individually recovering the $\beta$
value for both stars. We found that this is impossible for a primary near to
central hydrogen exhaustion, while in the other cases the fitted $\beta$ are
consistent, but always biased. Finally, the possibility to distinguish between
models computed with mild overshooting from models with no overshooting
resulted in a reassuring power of 80%. However, the scenario with a primary in
the central helium burning showed a power lower than 5%.
|
astro-ph.SR
|
we evaluated the bias and variability on the fitted age and convective core overshooting parameter for evolved binary stars accounting for observational and internal uncertainties we considered a binary system composed of a 250 m_sun primary star coupled with a 238 m_sun secondary in three evolutionary stages primary at the end of the central helium burning at the bottom of the rgb and in the helium core burning the simulations have been carried out for two values of accuracy on the mass determination 1 and 01 we found that the fitted age and overshooting efficiency are always biased towards low values the underestimation is relevant for a primary in the central helium burning stage reaching 85 in age and 004 25 relative error in the overshooting parameter beta in the other scenarios an undervaluation of the age by about 4 occurs a large variability in the fitted values between simulations was found for an individual system calibration the value of beta can vary from 00 to 026 for an error of 01 on the masses the global variability is suppressed by a factor of two we accounted for a systematic offset in the effective temperature of the stars by pm 150 k for a mass error of 1 beta is largely biased towards the edges of the explored range while for the lower mass uncertainty it is basically unconstrained from 00 to 02 we evaluated the possibility of individually recovering the beta value for both stars we found that this is impossible for a primary near to central hydrogen exhaustion while in the other cases the fitted beta are consistent but always biased finally the possibility to distinguish between models computed with mild overshooting from models with no overshooting resulted in a reassuring power of 80 however the scenario with a primary in the central helium burning showed a power lower than 5
|
[['we', 'evaluated', 'the', 'bias', 'and', 'variability', 'on', 'the', 'fitted', 'age', 'and', 'convective', 'core', 'overshooting', 'parameter', 'for', 'evolved', 'binary', 'stars', 'accounting', 'for', 'observational', 'and', 'internal', 'uncertainties', 'we', 'considered', 'a', 'binary', 'system', 'composed', 'of', 'a', '250', 'm_sun', 'primary', 'star', 'coupled', 'with', 'a', '238', 'm_sun', 'secondary', 'in', 'three', 'evolutionary', 'stages', 'primary', 'at', 'the', 'end', 'of', 'the', 'central', 'helium', 'burning', 'at', 'the', 'bottom', 'of', 'the', 'rgb', 'and', 'in', 'the', 'helium', 'core', 'burning', 'the', 'simulations', 'have', 'been', 'carried', 'out', 'for', 'two', 'values', 'of', 'accuracy', 'on', 'the', 'mass', 'determination', '1', 'and', '01', 'we', 'found', 'that', 'the', 'fitted', 'age', 'and', 'overshooting', 'efficiency', 'are', 'always', 'biased', 'towards', 'low', 'values', 'the', 'underestimation', 'is', 'relevant', 'for', 'a', 'primary', 'in', 'the', 'central', 'helium', 'burning', 'stage', 'reaching', '85', 'in', 'age', 'and', '004', '25', 'relative', 'error', 'in', 'the', 'overshooting', 'parameter', 'beta', 'in', 'the', 'other', 'scenarios', 'an', 'undervaluation', 'of', 'the', 'age', 'by', 'about', '4', 'occurs', 'a', 'large', 'variability', 'in', 'the', 'fitted', 'values', 'between', 'simulations', 'was', 'found', 'for', 'an', 'individual', 'system', 'calibration', 'the', 'value', 'of', 'beta', 'can', 'vary', 'from', '00', 'to', '026', 'for', 'an', 'error', 'of', '01', 'on', 'the', 'masses', 'the', 'global', 'variability', 'is', 'suppressed', 'by', 'a', 'factor', 'of', 'two', 'we', 'accounted', 'for', 'a', 'systematic', 'offset', 'in', 'the', 'effective', 'temperature', 'of', 'the', 'stars', 'by', 'pm', '150', 'k', 'for', 'a', 'mass', 'error', 'of', '1', 'beta', 'is', 'largely', 'biased', 'towards', 'the', 'edges', 'of', 'the', 'explored', 'range', 'while', 'for', 'the', 'lower', 'mass', 'uncertainty', 'it', 'is', 'basically', 'unconstrained', 'from', '00', 'to', '02', 'we', 'evaluated', 'the', 'possibility', 'of', 'individually', 'recovering', 'the', 'beta', 'value', 'for', 'both', 'stars', 'we', 'found', 'that', 'this', 'is', 'impossible', 'for', 'a', 'primary', 'near', 'to', 'central', 'hydrogen', 'exhaustion', 'while', 'in', 'the', 'other', 'cases', 'the', 'fitted', 'beta', 'are', 'consistent', 'but', 'always', 'biased', 'finally', 'the', 'possibility', 'to', 'distinguish', 'between', 'models', 'computed', 'with', 'mild', 'overshooting', 'from', 'models', 'with', 'no', 'overshooting', 'resulted', 'in', 'a', 'reassuring', 'power', 'of', '80', 'however', 'the', 'scenario', 'with', 'a', 'primary', 'in', 'the', 'central', 'helium', 'burning', 'showed', 'a', 'power', 'lower', 'than', '5']]
|
[-0.06555419817519265, 0.16115066350768537, -0.0274603050045919, 0.07877684933289264, 0.01104018942173273, -0.1036673142926577, 0.11391848337928803, 0.37736162293654757, -0.20098795907232708, -0.37341344523758363, 0.09314555313234357, -0.27776311063311826, 0.013748861372883888, 0.19883835379305048, -0.06092752022970218, 0.0028021803246896576, 0.07792615110780628, 0.03682561106414507, -0.09031990506260777, -0.19532958766558586, 0.2950267194615552, 0.06121985698580004, 0.18242861322903137, 0.014322960954576065, 0.04746670863228871, -0.09925677382666916, -0.03681903397337126, -0.016367354495120067, -0.15236329989376315, 0.049806593897969674, 0.2099773368329606, 0.0814967517355701, 0.25964589016184736, -0.32390426375163783, -0.20641439903442696, 0.07789544050136177, 0.17730066320076346, 0.04338046944307419, -0.06524594755844769, -0.2052689581936874, 0.09905243977590407, -0.1981299098011273, -0.14082188391462921, 0.05952584834697957, 0.06554062408023177, -0.006607616340336851, -0.29633829308028065, 0.14210078931410244, 0.028442834488815627, 0.06831184134910853, -0.09573241016322065, -0.20916106882460486, -0.0673615713663304, 0.13727969871521495, 0.041975364417150864, 0.049675084197222025, 0.1352144058447141, -0.13699679828945177, 0.003777502104268073, 0.37423577701178984, -0.0848331384412582, -0.10108263011666212, 0.16720627496218363, -0.16002257736161732, -0.14633680148661649, 0.14999730955473126, 0.1397201030702217, 0.11106617499950726, -0.1448903469072756, -0.006380503897993311, 0.05437467674822948, 0.23085082779763438, 0.06171572186386052, -0.038938581414621906, 0.2732459716379833, 0.19118687668264792, 0.021665592739260355, 0.06033401450360962, -0.1755278539918616, -0.08951042876683009, -0.25569613527554197, -0.0909726457512631, -0.10338977834852502, 0.05795860635161328, -0.1396076173872405, -0.11753359413036285, 0.35263697318316173, 0.12834189509520658, 0.2209310527748098, 0.043076181023667295, 0.278970991151211, 0.11936399152951714, 0.0722569247913032, 0.09337131902515984, 0.32415935795266215, 0.1690213617477447, 0.06924511175364637, -0.24244364567871649, 0.09589267503983451, -0.023430772143573808]
|
1,803.07059
|
Autonomous Scanning Probe Microscopy in-situ Tip Conditioning through
Machine Learning
|
Atomic scale characterization and manipulation with scanning probe microscopy
rely upon the use of an atomically sharp probe. Here we present automated
methods based on machine learning to automatically detect and recondition the
quality of the probe of a scanning tunneling microscope. As a model system, we
employ these techniques on the technologically relevant hydrogen-terminated
silicon surface, training the network to recognize abnormalities in the
appearance of surface dangling bonds. Of the machine learning methods tested, a
convolutional neural network yielded the greatest accuracy, achieving a
positive identification of degraded tips in 97% of the test cases. By using
multiple points of comparison and majority voting, the accuracy of the method
is improved beyond 99%. The methods described here can easily be generalized to
other material systems and nanoscale imaging techniques.
|
cond-mat.mes-hall
|
atomic scale characterization and manipulation with scanning probe microscopy rely upon the use of an atomically sharp probe here we present automated methods based on machine learning to automatically detect and recondition the quality of the probe of a scanning tunneling microscope as a model system we employ these techniques on the technologically relevant hydrogenterminated silicon surface training the network to recognize abnormalities in the appearance of surface dangling bonds of the machine learning methods tested a convolutional neural network yielded the greatest accuracy achieving a positive identification of degraded tips in 97 of the test cases by using multiple points of comparison and majority voting the accuracy of the method is improved beyond 99 the methods described here can easily be generalized to other material systems and nanoscale imaging techniques
|
[['atomic', 'scale', 'characterization', 'and', 'manipulation', 'with', 'scanning', 'probe', 'microscopy', 'rely', 'upon', 'the', 'use', 'of', 'an', 'atomically', 'sharp', 'probe', 'here', 'we', 'present', 'automated', 'methods', 'based', 'on', 'machine', 'learning', 'to', 'automatically', 'detect', 'and', 'recondition', 'the', 'quality', 'of', 'the', 'probe', 'of', 'a', 'scanning', 'tunneling', 'microscope', 'as', 'a', 'model', 'system', 'we', 'employ', 'these', 'techniques', 'on', 'the', 'technologically', 'relevant', 'hydrogenterminated', 'silicon', 'surface', 'training', 'the', 'network', 'to', 'recognize', 'abnormalities', 'in', 'the', 'appearance', 'of', 'surface', 'dangling', 'bonds', 'of', 'the', 'machine', 'learning', 'methods', 'tested', 'a', 'convolutional', 'neural', 'network', 'yielded', 'the', 'greatest', 'accuracy', 'achieving', 'a', 'positive', 'identification', 'of', 'degraded', 'tips', 'in', '97', 'of', 'the', 'test', 'cases', 'by', 'using', 'multiple', 'points', 'of', 'comparison', 'and', 'majority', 'voting', 'the', 'accuracy', 'of', 'the', 'method', 'is', 'improved', 'beyond', '99', 'the', 'methods', 'described', 'here', 'can', 'easily', 'be', 'generalized', 'to', 'other', 'material', 'systems', 'and', 'nanoscale', 'imaging', 'techniques']]
|
[-0.058098406204109554, 0.021284658416598247, -0.07159917444622119, 0.032186657799059486, -0.04004430179377549, -0.21973471458155291, 0.09568390984733355, 0.41022670371386843, -0.25204667750077736, -0.34310944397926674, 0.0728535356679007, -0.2839056472685046, -0.1620563739441506, 0.24693662829462523, -0.0721646952674989, 0.10071637021743814, 0.07356772994807431, -0.026956596569947273, -0.07250510513754065, -0.259739930037665, 0.26917019557520633, 0.057865909379391525, 0.3517148477942434, 0.061486520670276164, 0.11315355826709561, 0.008773733584924764, -0.006327574493679865, 0.020332129164838265, -0.1159128711709063, 0.19342096937635472, 0.27217166006870797, 0.10417030987124054, 0.28201091000170425, -0.46847117734221627, -0.21899416512020559, 0.04565690341277825, 0.14452306999476583, 0.14537342953964896, -0.0351047393890766, -0.3207918794271145, 0.05998369423007834, -0.11735685132017346, -0.07761111846264765, -0.15687245134093608, -0.08442544302981318, 0.016526104116328915, -0.21589820723596762, 0.04076953461786505, 0.029734092361990448, 0.12122400984157389, -0.06465396375701059, -0.06696657809510628, 0.011575175380602635, 0.11726238485603444, -0.04412878537861602, 0.04196976585036414, 0.2104945801609935, -0.17052244754038923, -0.16012352041701097, 0.3369200344744871, -0.06606929934981727, -0.14372082912000536, 0.2309620045854191, -0.0891352873579919, -0.10455235769218615, 0.12719654627073243, 0.18727800556465643, 0.16194462693893558, -0.17711633169056692, 0.011089122674718076, 0.015017094851279531, 0.20310439540514055, 0.10525097756269779, 0.03177554130319591, 0.20337052801126287, 0.27256593406769153, 0.037271084316352114, 0.10459700171286525, -0.20317887228678996, 0.025066105793727887, -0.19336842172663615, -0.16651721099233396, -0.20886168634263044, -0.002396864532173135, -0.06845535672019158, -0.18992613901505034, 0.3847269008561741, 0.19962392085167857, 0.1721790287206447, 0.006807308521420332, 0.33350092876446613, 0.016571283840773384, 0.11702975955656694, -0.008844893567889702, 0.24531285796947208, 0.09055761877226977, 0.08651249703705909, -0.21200724662892975, 0.0982548690770703, 0.03014040766781523]
|
1,803.0706
|
Emergent geometric frustration and flat band in moir\'e bilayer graphene
|
So far the physics of moir\'e graphene bilayers at large, incommensurate
rotation angles has been considered uninteresting. It has been held that the
interlayer coupling in such structures is weak and the system can be thought of
as a pair of decoupled single graphene sheets to a good approximation. Here, we
demonstrate that for large rotation angles near commensurate ones, the
interlayer coupling, far from being weak, is able to completely localize
electrons to within a large scale, geometrically frustrated network of
topologically protected modes. The emergent geometric frustration of the system
gives rise to completely flat bands, with strong correlation physics as a
result. All of this arises although in the lattice structure no large scale
pattern appears to the unguided eye. Sufficiently close to commensuration the
low-energy physics of this remarkable system has an exact analytical solution.
|
cond-mat.mes-hall cond-mat.str-el
|
so far the physics of moire graphene bilayers at large incommensurate rotation angles has been considered uninteresting it has been held that the interlayer coupling in such structures is weak and the system can be thought of as a pair of decoupled single graphene sheets to a good approximation here we demonstrate that for large rotation angles near commensurate ones the interlayer coupling far from being weak is able to completely localize electrons to within a large scale geometrically frustrated network of topologically protected modes the emergent geometric frustration of the system gives rise to completely flat bands with strong correlation physics as a result all of this arises although in the lattice structure no large scale pattern appears to the unguided eye sufficiently close to commensuration the lowenergy physics of this remarkable system has an exact analytical solution
|
[['so', 'far', 'the', 'physics', 'of', 'moire', 'graphene', 'bilayers', 'at', 'large', 'incommensurate', 'rotation', 'angles', 'has', 'been', 'considered', 'uninteresting', 'it', 'has', 'been', 'held', 'that', 'the', 'interlayer', 'coupling', 'in', 'such', 'structures', 'is', 'weak', 'and', 'the', 'system', 'can', 'be', 'thought', 'of', 'as', 'a', 'pair', 'of', 'decoupled', 'single', 'graphene', 'sheets', 'to', 'a', 'good', 'approximation', 'here', 'we', 'demonstrate', 'that', 'for', 'large', 'rotation', 'angles', 'near', 'commensurate', 'ones', 'the', 'interlayer', 'coupling', 'far', 'from', 'being', 'weak', 'is', 'able', 'to', 'completely', 'localize', 'electrons', 'to', 'within', 'a', 'large', 'scale', 'geometrically', 'frustrated', 'network', 'of', 'topologically', 'protected', 'modes', 'the', 'emergent', 'geometric', 'frustration', 'of', 'the', 'system', 'gives', 'rise', 'to', 'completely', 'flat', 'bands', 'with', 'strong', 'correlation', 'physics', 'as', 'a', 'result', 'all', 'of', 'this', 'arises', 'although', 'in', 'the', 'lattice', 'structure', 'no', 'large', 'scale', 'pattern', 'appears', 'to', 'the', 'unguided', 'eye', 'sufficiently', 'close', 'to', 'commensuration', 'the', 'lowenergy', 'physics', 'of', 'this', 'remarkable', 'system', 'has', 'an', 'exact', 'analytical', 'solution']]
|
[-0.20140890057346106, 0.1836415879486385, -0.06695305048521581, 0.08035818944524357, -0.06513630984503467, -0.1731927030411609, 0.026061558884923623, 0.3667926599083991, -0.3128245440914745, -0.2967086514121377, 0.03295375778098597, -0.2837910333098911, -0.15651439743036097, 0.14654849768488956, 0.005033658453926658, 0.021859702250498127, 0.008246182319590916, -0.021487876144740327, -0.05780447888181364, -0.1727859301160914, 0.2674729721118167, 0.06689611059050712, 0.2940366230871555, 0.07569544696460123, 0.08236009875486652, -0.04764013670605989, 0.10718198733617008, 0.058210020813682255, -0.11321402551899848, 0.056959659189468236, 0.24937489930969134, -0.05067648301437069, 0.2079687388027556, -0.42615527691815397, -0.17140151069184645, 0.04581144976885252, 0.1747371035715123, 0.19899450529118826, -0.0501916891788032, -0.2788081814027425, 0.07094000812231314, -0.1430247869315765, -0.157144288371632, -0.09259946717725306, 0.027075100656625606, -0.0423767142527127, -0.2366505694804251, 0.06525526506484573, 0.05433522781236566, 0.07513134133928329, -0.03885379603146006, -0.0788804524077317, -0.06200995831750333, 0.14141837221389408, 0.09891326632015675, 0.07904526230497219, 0.0904683509084443, -0.12421828033670569, -0.0853743180226394, 0.4163201992339689, -0.03781969592573202, -0.15415174193117473, 0.242904887040541, -0.1885453098966144, -0.09469891633677611, 0.1989956655197864, 0.12689356857629344, 0.0676895371996697, -0.1264862308430271, 0.10228846490461875, -0.08733257586002457, 0.19119978746777844, 0.05334004240693431, 0.07780049032642232, 0.282691634796131, 0.17723817367897296, 0.09188363673634452, 0.11326766694416862, -0.10025084796093618, -0.0795199081047083, -0.2409097859635949, -0.08809172024819732, -0.2226826621884507, 0.08135733140712913, -0.049645590270838445, -0.22385174232927024, 0.38481094949148437, 0.11649117740742165, 0.2019122094441549, -0.03526833245352542, 0.24285150196054855, 0.08478167402078968, 0.1411614253875806, 0.01618097953015952, 0.33008140413318393, 0.12088143115648799, 0.07887109747263703, -0.18858833404311495, 0.04931374305604602, 0.01173683538469285]
|
1,803.07061
|
Coupling of magnetic order and charge transport in the candidate Dirac
semimetal EuCd$_2$As$_2$
|
We use resonant elastic x-ray scattering to determine the evolution of
magnetic order in EuCd$_2$As$_2$ below $T_\textrm{N}=9.5$\,K, as a function of
temperature and applied magnetic field. We find an A-type
antiferromagneticstructure with in-plane magnetic moments, and observe dramatic
magnetoresistive effects associated with field-induced changes in the magnetic
structure and domain populations. Our \textit{ab initio} electronic structure
calculations indicate that the Dirac dispersion found in the nonmagnetic Dirac
semimetal Cd$_3$As$_2$ is also present in EuCd$_2$As$_2$, but is gapped for $T
< T_\textrm{N}$ due to the breaking of $C_3$ symmetry by the magnetic
structure.
|
cond-mat.str-el
|
we use resonant elastic xray scattering to determine the evolution of magnetic order in eucd_2as_2 below t_textrmn95k as a function of temperature and applied magnetic field we find an atype antiferromagneticstructure with inplane magnetic moments and observe dramatic magnetoresistive effects associated with fieldinduced changes in the magnetic structure and domain populations our textitab initio electronic structure calculations indicate that the dirac dispersion found in the nonmagnetic dirac semimetal cd_3as_2 is also present in eucd_2as_2 but is gapped for t t_textrmn due to the breaking of c_3 symmetry by the magnetic structure
|
[['we', 'use', 'resonant', 'elastic', 'xray', 'scattering', 'to', 'determine', 'the', 'evolution', 'of', 'magnetic', 'order', 'in', 'eucd_2as_2', 'below', 't_textrmn95k', 'as', 'a', 'function', 'of', 'temperature', 'and', 'applied', 'magnetic', 'field', 'we', 'find', 'an', 'atype', 'antiferromagneticstructure', 'with', 'inplane', 'magnetic', 'moments', 'and', 'observe', 'dramatic', 'magnetoresistive', 'effects', 'associated', 'with', 'fieldinduced', 'changes', 'in', 'the', 'magnetic', 'structure', 'and', 'domain', 'populations', 'our', 'textitab', 'initio', 'electronic', 'structure', 'calculations', 'indicate', 'that', 'the', 'dirac', 'dispersion', 'found', 'in', 'the', 'nonmagnetic', 'dirac', 'semimetal', 'cd_3as_2', 'is', 'also', 'present', 'in', 'eucd_2as_2', 'but', 'is', 'gapped', 'for', 't', 't_textrmn', 'due', 'to', 'the', 'breaking', 'of', 'c_3', 'symmetry', 'by', 'the', 'magnetic', 'structure']]
|
[-0.1887802759661559, 0.21868088302412464, -0.03139571758677785, 0.03494739044572781, -0.09124609414655506, -0.06297442946436532, 0.05518065820176029, 0.4372894097579999, -0.2752346112759093, -0.339231416855133, -0.031492020118604885, -0.30961287406723154, -0.16353513347508197, 0.12773273561641657, 0.10518236082633224, -0.013040198703830162, -0.04738664605100168, 0.003363099917141574, -0.13452308879003683, -0.16790551739598342, 0.3057204315731867, -0.0020586245986266754, 0.27441513646142873, 0.08911581953275907, 0.001591618876548463, -0.0027959336921719188, 0.12240596230696427, 0.027040598610562554, -0.13583410322298936, 0.0036753575060695797, 0.2171579849424908, -0.14261104745183434, 0.1330416917544528, -0.4551937725143821, -0.2006612740394272, -0.021327562844694666, 0.15496735929856809, 0.13858078746909924, -0.10785898009676151, -0.27250343634422575, 0.06703826914844888, -0.11074146496529659, -0.16757370385582024, -0.16465634407391877, -0.006857260730734953, -0.02652814013234685, -0.24277630196609587, 0.1366469781042019, 0.031032936180565046, 0.1343785814562089, -0.1712062000584778, -0.12599930852086524, -0.10983066194889586, 0.02186764045252224, 0.08822197952108939, 0.09140505783490083, 0.13536137254160482, -0.11205579360274681, -0.12973331618175077, 0.38780987455922944, -0.06292114850117961, -0.04910972905920798, 0.11950169480667355, -0.23792694305498782, -0.12206280949326713, 0.17506241659225708, 0.1134719488870227, 0.08230622450747851, -0.10036076721931504, 0.11250925785404096, 0.024775139143784645, 0.18123671605011052, 0.010161332252403994, 0.04287579134525208, 0.24789939789373552, 0.1560947203359912, 0.031890630899938974, 0.13625605680634467, -0.16344881742169787, 0.0034362074835330584, -0.22051872223029645, -0.1456102014341381, -0.19376193199913655, 0.08624638547451141, -0.05705640167262787, -0.24356705719981803, 0.3789864810277823, 0.16785274462753466, 0.16645545396545713, -0.0814672262889197, 0.2303140244519945, 0.11601966897318705, 0.09416668880416938, 0.07928360175875047, 0.26640538395162716, 0.23791599137122543, 0.13905745834436561, -0.35850052009179684, 0.06707089272683507, -0.01568787084536606]
|
1,803.07062
|
Asymptotic behaviour of neuron population models structured by
elapsed-time
|
We study two population models describing the dynamics of interacting
neurons, initially proposed by Pakdaman, Perthame, and Salort (2010, 2014). In
the first model, the structuring variable $s$ represents the time elapsed since
its last discharge, while in the second one neurons exhibit a fatigue property
and the structuring variable is a generic "state". We prove existence of
solutions and steady states in the space of finite, nonnegative measures.
Furthermore, we show that solutions converge to the equilibrium exponentially
in time in the case of weak nonlinearity (i.e., weak connectivity). The main
innovation is the use of Doeblin's theorem from probability in order to show
the existence of a spectral gap property in the linear (no-connectivity)
setting. Relaxation to the steady state for the nonlinear models is then proved
by a constructive perturbation argument.
|
math.AP
|
we study two population models describing the dynamics of interacting neurons initially proposed by pakdaman perthame and salort 2010 2014 in the first model the structuring variable s represents the time elapsed since its last discharge while in the second one neurons exhibit a fatigue property and the structuring variable is a generic state we prove existence of solutions and steady states in the space of finite nonnegative measures furthermore we show that solutions converge to the equilibrium exponentially in time in the case of weak nonlinearity ie weak connectivity the main innovation is the use of doeblins theorem from probability in order to show the existence of a spectral gap property in the linear noconnectivity setting relaxation to the steady state for the nonlinear models is then proved by a constructive perturbation argument
|
[['we', 'study', 'two', 'population', 'models', 'describing', 'the', 'dynamics', 'of', 'interacting', 'neurons', 'initially', 'proposed', 'by', 'pakdaman', 'perthame', 'and', 'salort', '2010', '2014', 'in', 'the', 'first', 'model', 'the', 'structuring', 'variable', 's', 'represents', 'the', 'time', 'elapsed', 'since', 'its', 'last', 'discharge', 'while', 'in', 'the', 'second', 'one', 'neurons', 'exhibit', 'a', 'fatigue', 'property', 'and', 'the', 'structuring', 'variable', 'is', 'a', 'generic', 'state', 'we', 'prove', 'existence', 'of', 'solutions', 'and', 'steady', 'states', 'in', 'the', 'space', 'of', 'finite', 'nonnegative', 'measures', 'furthermore', 'we', 'show', 'that', 'solutions', 'converge', 'to', 'the', 'equilibrium', 'exponentially', 'in', 'time', 'in', 'the', 'case', 'of', 'weak', 'nonlinearity', 'ie', 'weak', 'connectivity', 'the', 'main', 'innovation', 'is', 'the', 'use', 'of', 'doeblins', 'theorem', 'from', 'probability', 'in', 'order', 'to', 'show', 'the', 'existence', 'of', 'a', 'spectral', 'gap', 'property', 'in', 'the', 'linear', 'noconnectivity', 'setting', 'relaxation', 'to', 'the', 'steady', 'state', 'for', 'the', 'nonlinear', 'models', 'is', 'then', 'proved', 'by', 'a', 'constructive', 'perturbation', 'argument']]
|
[-0.137542431522861, 0.1124431274742014, -0.11127823409169241, 0.0551424742425981, -0.013160658012935542, -0.12425625168445303, 0.04336752387505949, 0.31700601983339266, -0.2764735984076795, -0.22907059410712996, 0.10844013393643011, -0.253083455474361, -0.15006576004242034, 0.13084355901569633, -0.0511391333582692, 0.06051723105453053, 0.05184297015036183, 0.04388038184199678, -0.010239924698073725, -0.23627366298193433, 0.32494967454638246, -0.013312080087266247, 0.2746811122966132, 0.020569544677671633, 0.11652763677354817, -0.01802916481698814, 0.000986349345289899, 0.010732046184716466, -0.11664191960678584, 0.07106391365484062, 0.2226409387022114, 0.10876831358396694, 0.3438689730837381, -0.41574918319422166, -0.22009450060322433, 0.10940577821890102, 0.09214957407850743, 0.10783768187389058, -0.00668781478469141, -0.27474285437921553, 0.08133623562315549, -0.13728370087543376, -0.1595861829057532, -0.054924368301644585, 0.06814342957774275, 0.06028372301200153, -0.2797933809942377, 0.10232088190706488, 0.13338142169527428, 0.008382173884210099, -0.10876991825013708, -0.03297877908313185, -0.039006682883079784, 0.0998015243777151, 0.055840617354742175, 0.003942722227088267, 0.0574327896496183, -0.12301876181316443, -0.11039002460805714, 0.29538464215514076, -0.10543358497255083, -0.16993085055347687, 0.19641716893118127, -0.15574260836264076, -0.13098004640472172, 0.10728798820672178, 0.15411282318847297, 0.12811346847872088, -0.133651599736142, 0.11364987628277097, -0.04079127817631776, 0.18045510829223277, 0.06336568158007878, 0.0045894311173798, 0.12096421852787953, 0.1789597618670196, 0.10754259413150244, 0.15555639451551706, -0.04325174087486965, -0.13088474185311033, -0.29916851740869643, -0.1655033127530793, -0.19629985322699622, 0.05812249340369065, -0.07795678829755441, -0.16642111064376017, 0.4441247746817544, 0.11862400773198421, 0.1803936992441059, 0.0930500180071878, 0.22906283603865596, 0.14517963798086447, -0.01849891502704275, 0.1048458770260607, 0.24649392648887142, 0.1670407818007122, 0.11743860460705775, -0.21677474837940136, 0.10589569940448816, 0.11300847377572068]
|
1,803.07063
|
Quantized Dehydration and the Determinants of Selectivity in the NaChBac
Bacterial Sodium Channel
|
A discrete electrostatic/diffusion model has been developed to describe the
selective permeation of ion channels, based on ionic Coulomb blockade (ICB) and
quantised dehydration (QD). It has been applied to describe selectivity
phenomena measured in the bacterial NaChBac sodium channel and some of its
mutants. Site-directed mutagenesis and the whole-cell patch-clamp technique
were used to investigate how the value $Q_f$ of the fixed charge at the
selectivity filter (SF) affected both valence and alike-charge selectivity. The
new ICB/QD model predicts that increasing ${Q_f}$ should lead to a shift of
selectivity sequences towards larger ion sizes and charges, a result that
agrees with the present experiments and with earlier work. Comparison of the
model with experimental data provides evidence for an {\it effective charge}
$Q_f^*$ at the SF that is smaller in magnitude than the nominal $Q_f$
corresponding to the charge on the isolated protein residues. Furthermore,
$Q_f^*$ was different for aspartate and glutamate charged rings and also
depended on their position within the SF. It is suggested that protonation of
the residues within the restricted space is an important factor in
significantly reducing the effective charge of the EEEE ring. Values of $Q_f^*$
derived from experiments on the anomalous mole fraction effect (AMFE) agree
well with expectations based on the ICB/QD model and have led to the first
clear demonstration of the expected ICB oscillations in Ca$^{2+}$ conduction as
a function of the fixed charge. Pilot studies of the dependence of Ca$^{2+}$
conduction on pH are consistent with the predictions of the model.
|
physics.bio-ph q-bio.BM
|
a discrete electrostaticdiffusion model has been developed to describe the selective permeation of ion channels based on ionic coulomb blockade icb and quantised dehydration qd it has been applied to describe selectivity phenomena measured in the bacterial nachbac sodium channel and some of its mutants sitedirected mutagenesis and the wholecell patchclamp technique were used to investigate how the value q_f of the fixed charge at the selectivity filter sf affected both valence and alikecharge selectivity the new icbqd model predicts that increasing q_f should lead to a shift of selectivity sequences towards larger ion sizes and charges a result that agrees with the present experiments and with earlier work comparison of the model with experimental data provides evidence for an it effective charge q_f at the sf that is smaller in magnitude than the nominal q_f corresponding to the charge on the isolated protein residues furthermore q_f was different for aspartate and glutamate charged rings and also depended on their position within the sf it is suggested that protonation of the residues within the restricted space is an important factor in significantly reducing the effective charge of the eeee ring values of q_f derived from experiments on the anomalous mole fraction effect amfe agree well with expectations based on the icbqd model and have led to the first clear demonstration of the expected icb oscillations in ca2 conduction as a function of the fixed charge pilot studies of the dependence of ca2 conduction on ph are consistent with the predictions of the model
|
[['a', 'discrete', 'electrostaticdiffusion', 'model', 'has', 'been', 'developed', 'to', 'describe', 'the', 'selective', 'permeation', 'of', 'ion', 'channels', 'based', 'on', 'ionic', 'coulomb', 'blockade', 'icb', 'and', 'quantised', 'dehydration', 'qd', 'it', 'has', 'been', 'applied', 'to', 'describe', 'selectivity', 'phenomena', 'measured', 'in', 'the', 'bacterial', 'nachbac', 'sodium', 'channel', 'and', 'some', 'of', 'its', 'mutants', 'sitedirected', 'mutagenesis', 'and', 'the', 'wholecell', 'patchclamp', 'technique', 'were', 'used', 'to', 'investigate', 'how', 'the', 'value', 'q_f', 'of', 'the', 'fixed', 'charge', 'at', 'the', 'selectivity', 'filter', 'sf', 'affected', 'both', 'valence', 'and', 'alikecharge', 'selectivity', 'the', 'new', 'icbqd', 'model', 'predicts', 'that', 'increasing', 'q_f', 'should', 'lead', 'to', 'a', 'shift', 'of', 'selectivity', 'sequences', 'towards', 'larger', 'ion', 'sizes', 'and', 'charges', 'a', 'result', 'that', 'agrees', 'with', 'the', 'present', 'experiments', 'and', 'with', 'earlier', 'work', 'comparison', 'of', 'the', 'model', 'with', 'experimental', 'data', 'provides', 'evidence', 'for', 'an', 'it', 'effective', 'charge', 'q_f', 'at', 'the', 'sf', 'that', 'is', 'smaller', 'in', 'magnitude', 'than', 'the', 'nominal', 'q_f', 'corresponding', 'to', 'the', 'charge', 'on', 'the', 'isolated', 'protein', 'residues', 'furthermore', 'q_f', 'was', 'different', 'for', 'aspartate', 'and', 'glutamate', 'charged', 'rings', 'and', 'also', 'depended', 'on', 'their', 'position', 'within', 'the', 'sf', 'it', 'is', 'suggested', 'that', 'protonation', 'of', 'the', 'residues', 'within', 'the', 'restricted', 'space', 'is', 'an', 'important', 'factor', 'in', 'significantly', 'reducing', 'the', 'effective', 'charge', 'of', 'the', 'eeee', 'ring', 'values', 'of', 'q_f', 'derived', 'from', 'experiments', 'on', 'the', 'anomalous', 'mole', 'fraction', 'effect', 'amfe', 'agree', 'well', 'with', 'expectations', 'based', 'on', 'the', 'icbqd', 'model', 'and', 'have', 'led', 'to', 'the', 'first', 'clear', 'demonstration', 'of', 'the', 'expected', 'icb', 'oscillations', 'in', 'ca2', 'conduction', 'as', 'a', 'function', 'of', 'the', 'fixed', 'charge', 'pilot', 'studies', 'of', 'the', 'dependence', 'of', 'ca2', 'conduction', 'on', 'ph', 'are', 'consistent', 'with', 'the', 'predictions', 'of', 'the', 'model']]
|
[-0.07467152885849547, 0.14936663286003515, -0.0426860175667757, 0.044340071680742395, 0.010598861475159082, -0.1381769650260428, 0.06655353230815081, 0.36104750525520507, -0.20594352997180698, -0.2937747318312586, 0.023236689299913536, -0.28920218957042, -0.1202890480579584, 0.16732536872893752, -0.029544037899277866, 0.007615114187545435, 0.015457553622812167, 0.038122503007444214, -0.03623581917144837, -0.18320860215799367, 0.2500249612178788, 0.10855319549693786, 0.3017685000296592, 0.1192971539878133, 0.08245950300212815, 0.003626033239932469, -0.011359070799870783, 0.020509636003302457, -0.15594513213803596, 0.10367437361750796, 0.19831270138718127, 0.03200196095529091, 0.20388281740150957, -0.42055049066592654, -0.20004208830052456, 0.07014954729327356, 0.13766168646821117, 0.13580839896208072, -0.07332347184662748, -0.24007070180492468, 0.09740595899411968, -0.1704788398134137, -0.10469371546013094, -0.0268583037118132, 0.05243768788552488, 0.05502175762463944, -0.2756266249904791, 0.109045134320454, 0.03710688567410848, 0.06660609516169293, -0.09759443978840732, -0.18218653525663428, -0.07481204118134537, 0.12089333316240175, 0.06116589116835854, 0.046108675960275576, 0.2036029304991136, -0.0987860483704621, -0.0987636068199778, 0.33554127778536286, -0.06371345667545562, -0.1648264509760382, 0.18875419846796673, -0.17299245172329847, -0.0808458671676945, 0.1800925266932711, 0.10594073185102498, 0.09598462600036557, -0.1096006413046495, 0.045615267526334054, -0.036210802112552655, 0.18383858583453902, 0.06688235103560379, 0.037437366595656336, 0.18975447211905483, 0.19074729118023037, 0.02738014659407197, 0.11371282666108579, -0.11356626396454557, -0.08108834925633163, -0.2399354867719443, -0.1445265617520814, -0.14635410138880872, 0.017698920461869085, -0.05307896576402662, -0.1239399710973074, 0.40697985080720195, 0.1291565681886242, 0.21667358937325426, 0.015010608405054334, 0.23012613668200002, 0.10390832124700598, 0.12110291083996001, -0.014521899709784722, 0.22784839183371233, 0.13896787690417653, 0.09053125459257604, -0.31990543367101787, 0.11932896386951687, 0.019303625828238677]
|
1,803.07064
|
Far-ultraviolet Spectroscopy of Recent Comets with the Cosmic Origins
Spectrograph on the Hubble Space Telescope
|
Since its launch in 1990, the Hubble Space Telescope (HST) has served as a
platform with unique capabilities for remote observations of comets in the
far-ultraviolet region of the spectrum. Successive generations of imagers and
spectrographs have seen large advances in sensitivity and spectral resolution
enabling observations of the diverse properties of a representative number of
comets during the past 25 years. To date, four comets have been observed in the
far-ultraviolet by the Cosmic Origins Spectrograph (COS), the last spectrograph
to be installed in HST, in 2009: 103P/Hartley 2, C/2009 P1 (Garradd), C/2012 S1
(ISON), and C/2014 Q2 (Lovejoy). COS has unprecedented sensitivity, but limited
spatial information in its 2.5 arcsec diameter circular aperture, and our
objective was to determine the CO production rates from measurements of the CO
Fourth Positive system in the spectral range of 1400 to 1700 A. In the two
brightest comets, nineteen bands of this system were clearly identified. The
water production rates were derived from nearly concurrent observations of the
OH (0,0) band at 3085 A by the Space Telescope Imaging Spectrograph (STIS). The
derived CO/H2O production rate ratio ranged from ~0.3% for Hartley 2 to ~22%
for Garradd. In addition, strong partially resolved emission features due to
multiplets of S I, centered at 1429 A and 1479 A, and of C I at 1561 A and 1657
A, were observed in all four comets. Weak emission from several lines of the H2
Lyman band system, excited by solar Lyman-alpha and Lyman-beta pumped
fluorescence, were detected in comet Lovejoy.
|
astro-ph.EP
|
since its launch in 1990 the hubble space telescope hst has served as a platform with unique capabilities for remote observations of comets in the farultraviolet region of the spectrum successive generations of imagers and spectrographs have seen large advances in sensitivity and spectral resolution enabling observations of the diverse properties of a representative number of comets during the past 25 years to date four comets have been observed in the farultraviolet by the cosmic origins spectrograph cos the last spectrograph to be installed in hst in 2009 103phartley 2 c2009 p1 garradd c2012 s1 ison and c2014 q2 lovejoy cos has unprecedented sensitivity but limited spatial information in its 25 arcsec diameter circular aperture and our objective was to determine the co production rates from measurements of the co fourth positive system in the spectral range of 1400 to 1700 a in the two brightest comets nineteen bands of this system were clearly identified the water production rates were derived from nearly concurrent observations of the oh 00 band at 3085 a by the space telescope imaging spectrograph stis the derived coh2o production rate ratio ranged from 03 for hartley 2 to 22 for garradd in addition strong partially resolved emission features due to multiplets of s i centered at 1429 a and 1479 a and of c i at 1561 a and 1657 a were observed in all four comets weak emission from several lines of the h2 lyman band system excited by solar lymanalpha and lymanbeta pumped fluorescence were detected in comet lovejoy
|
[['since', 'its', 'launch', 'in', '1990', 'the', 'hubble', 'space', 'telescope', 'hst', 'has', 'served', 'as', 'a', 'platform', 'with', 'unique', 'capabilities', 'for', 'remote', 'observations', 'of', 'comets', 'in', 'the', 'farultraviolet', 'region', 'of', 'the', 'spectrum', 'successive', 'generations', 'of', 'imagers', 'and', 'spectrographs', 'have', 'seen', 'large', 'advances', 'in', 'sensitivity', 'and', 'spectral', 'resolution', 'enabling', 'observations', 'of', 'the', 'diverse', 'properties', 'of', 'a', 'representative', 'number', 'of', 'comets', 'during', 'the', 'past', '25', 'years', 'to', 'date', 'four', 'comets', 'have', 'been', 'observed', 'in', 'the', 'farultraviolet', 'by', 'the', 'cosmic', 'origins', 'spectrograph', 'cos', 'the', 'last', 'spectrograph', 'to', 'be', 'installed', 'in', 'hst', 'in', '2009', '103phartley', '2', 'c2009', 'p1', 'garradd', 'c2012', 's1', 'ison', 'and', 'c2014', 'q2', 'lovejoy', 'cos', 'has', 'unprecedented', 'sensitivity', 'but', 'limited', 'spatial', 'information', 'in', 'its', '25', 'arcsec', 'diameter', 'circular', 'aperture', 'and', 'our', 'objective', 'was', 'to', 'determine', 'the', 'co', 'production', 'rates', 'from', 'measurements', 'of', 'the', 'co', 'fourth', 'positive', 'system', 'in', 'the', 'spectral', 'range', 'of', '1400', 'to', '1700', 'a', 'in', 'the', 'two', 'brightest', 'comets', 'nineteen', 'bands', 'of', 'this', 'system', 'were', 'clearly', 'identified', 'the', 'water', 'production', 'rates', 'were', 'derived', 'from', 'nearly', 'concurrent', 'observations', 'of', 'the', 'oh', '00', 'band', 'at', '3085', 'a', 'by', 'the', 'space', 'telescope', 'imaging', 'spectrograph', 'stis', 'the', 'derived', 'coh2o', 'production', 'rate', 'ratio', 'ranged', 'from', '03', 'for', 'hartley', '2', 'to', '22', 'for', 'garradd', 'in', 'addition', 'strong', 'partially', 'resolved', 'emission', 'features', 'due', 'to', 'multiplets', 'of', 's', 'i', 'centered', 'at', '1429', 'a', 'and', '1479', 'a', 'and', 'of', 'c', 'i', 'at', '1561', 'a', 'and', '1657', 'a', 'were', 'observed', 'in', 'all', 'four', 'comets', 'weak', 'emission', 'from', 'several', 'lines', 'of', 'the', 'h2', 'lyman', 'band', 'system', 'excited', 'by', 'solar', 'lymanalpha', 'and', 'lymanbeta', 'pumped', 'fluorescence', 'were', 'detected', 'in', 'comet', 'lovejoy']]
|
[-0.06474513539251348, 0.1294617179423767, -0.020981448085876764, 0.013746059317327308, -0.014912951412043185, -0.09981298603270261, 0.020310954700107686, 0.42283162905550853, -0.17513037894968875, -0.36093236328451894, 0.12371417966710396, -0.3388383566234552, -0.026067362803587457, 0.18842511701882358, -0.039861046526425525, -0.000567563098456958, 0.05759259900878533, -0.10069443792690436, -0.01080055425700266, -0.2547625617507947, 0.20953626528989844, 0.10708175936929365, 0.15641895046246646, -0.001002655379124917, 0.09261637501867881, -0.0862914551198628, -0.062123134299554295, -0.054846166905235805, -0.15463854919653386, 0.08359432968336478, 0.24720654314296553, 0.1429050365918556, 0.20563579651206965, -0.33843172450178827, -0.18473174915561685, 0.03360884840662948, 0.15153772650228348, -0.021471520481100015, 0.02259516224512481, -0.3156342018601208, 0.01939052960733534, -0.1481466348232061, -0.15965924670882714, 0.07989946140787652, 0.07139424369961489, 0.006589143395103747, -0.22609371248336174, 0.03689557583311398, -0.048287264054124535, 0.17046774079972238, -0.14397309487594612, -0.15223505093717904, -0.09169376070167345, 0.11429816541931359, 0.017949978646356612, 0.06616300206223968, 0.0896453020413901, -0.09355626979049703, -0.040946976716440986, 0.36207161487982376, -0.13017070648675144, 0.05684527639124326, 0.18847813102001965, -0.27208492390127503, -0.19987196936199325, 0.2636628044110694, 0.1511313028611312, 0.12665098824777488, -0.15260063475261632, 0.07829850001144223, -0.025559814472217113, 0.21403089265822928, 0.11813754028116819, 0.10504089952473805, 0.2458791997755725, 0.08357636344589991, 0.0060939840204810025, 0.06969803285642229, -0.32036418601637706, 0.0012142928608227521, -0.19662273904486938, -0.16417237168207066, -0.1308171629316348, 0.08195317469380825, -0.06354312022222075, -0.030090765074419323, 0.3452878568223241, 0.07458258802125783, 0.2144879432835296, 0.0074807852715821355, 0.28590741039988643, 0.023804619880593236, 0.1159538716597126, 0.0369853753809366, 0.35617604727030994, 0.1306451633904544, 0.19028772126148397, -0.1796469042683384, 0.036625444602123025, 0.011700961980750435]
|
1,803.07065
|
Sensorless Resonance Tracking of Resonant Electromagnetic Actuator
through Back-EMF Estimation for Mobile Devices
|
Resonant electromagnetic actuators have been broadly used as vibration motors
for mobile devices given their ability of generating relatively fast, strong,
and controllable vibration force at a given resonant frequency. Mechanism of
the actuators that is based on mechanical resonance, however, limits their use
to a situation where their resonant frequencies are known and unshifted. In
reality, there are many factors that alter the resonant frequency: for example,
manufacturing tolerances, worn mechanical components such as a spring,
nonlinearity in association with different input voltage levels. Here, we
describe a sensorless resonance tracking method that actuates the motor and
automatically detects its unknown damped natural frequency through the
estimation of back electromotive force (EMF) and inner mass movements. We
demonstrate the tracking performance of the proposed method through a series of
experiments. This approach has the potential to control residual vibrations and
then improve vibrotactile feedback, which can potentially be used for
human-computer interaction, cognitive and affective neuroscience research.
|
physics.app-ph cs.SY eess.SP math.DS
|
resonant electromagnetic actuators have been broadly used as vibration motors for mobile devices given their ability of generating relatively fast strong and controllable vibration force at a given resonant frequency mechanism of the actuators that is based on mechanical resonance however limits their use to a situation where their resonant frequencies are known and unshifted in reality there are many factors that alter the resonant frequency for example manufacturing tolerances worn mechanical components such as a spring nonlinearity in association with different input voltage levels here we describe a sensorless resonance tracking method that actuates the motor and automatically detects its unknown damped natural frequency through the estimation of back electromotive force emf and inner mass movements we demonstrate the tracking performance of the proposed method through a series of experiments this approach has the potential to control residual vibrations and then improve vibrotactile feedback which can potentially be used for humancomputer interaction cognitive and affective neuroscience research
|
[['resonant', 'electromagnetic', 'actuators', 'have', 'been', 'broadly', 'used', 'as', 'vibration', 'motors', 'for', 'mobile', 'devices', 'given', 'their', 'ability', 'of', 'generating', 'relatively', 'fast', 'strong', 'and', 'controllable', 'vibration', 'force', 'at', 'a', 'given', 'resonant', 'frequency', 'mechanism', 'of', 'the', 'actuators', 'that', 'is', 'based', 'on', 'mechanical', 'resonance', 'however', 'limits', 'their', 'use', 'to', 'a', 'situation', 'where', 'their', 'resonant', 'frequencies', 'are', 'known', 'and', 'unshifted', 'in', 'reality', 'there', 'are', 'many', 'factors', 'that', 'alter', 'the', 'resonant', 'frequency', 'for', 'example', 'manufacturing', 'tolerances', 'worn', 'mechanical', 'components', 'such', 'as', 'a', 'spring', 'nonlinearity', 'in', 'association', 'with', 'different', 'input', 'voltage', 'levels', 'here', 'we', 'describe', 'a', 'sensorless', 'resonance', 'tracking', 'method', 'that', 'actuates', 'the', 'motor', 'and', 'automatically', 'detects', 'its', 'unknown', 'damped', 'natural', 'frequency', 'through', 'the', 'estimation', 'of', 'back', 'electromotive', 'force', 'emf', 'and', 'inner', 'mass', 'movements', 'we', 'demonstrate', 'the', 'tracking', 'performance', 'of', 'the', 'proposed', 'method', 'through', 'a', 'series', 'of', 'experiments', 'this', 'approach', 'has', 'the', 'potential', 'to', 'control', 'residual', 'vibrations', 'and', 'then', 'improve', 'vibrotactile', 'feedback', 'which', 'can', 'potentially', 'be', 'used', 'for', 'humancomputer', 'interaction', 'cognitive', 'and', 'affective', 'neuroscience', 'research']]
|
[-0.14087299970155465, 0.13789697639538046, -0.04250472968833262, -0.0008752295029750448, -0.12438913386409418, -0.18581008688322728, 0.042002946300479245, 0.43158602263613405, -0.2709257598978149, -0.31662960318094, 0.060378354170972696, -0.23382883443780056, -0.21133057824394938, 0.27459339847894315, -0.07565877087638254, 0.08551361733517769, 0.04974913590052018, 0.04968487445848605, 0.06837835229337923, -0.12677478036825557, 0.23701390235897013, 0.05082428066319303, 0.3015307777375572, 0.0493093013720693, 0.13492333515889093, -0.016951525404082634, 0.03920857032725611, -0.0184988457572505, -0.05477932807866925, 0.11774311181381816, 0.28175247499838624, 0.07859862227393669, 0.3128037989563957, -0.46241092714893667, -0.1889030110869038, 0.0729644860684742, 0.1426002052111575, 0.10278239374894861, -0.07531966796937646, -0.302361463597398, 0.04573828721407188, -0.17606314551085234, -0.09035694444560537, -0.10237949360397798, 0.03744656677192808, 0.06957934799661819, -0.26938975277014926, 0.036899023213353054, 0.03461577704683229, 0.10044415731755191, -0.08803797598025258, -0.06922468322600368, -0.005203748337465451, 0.17930839929300144, 0.05453029548737539, -0.007761453310782208, 0.27961968273348825, -0.127482462076093, -0.11889622021537227, 0.36406600628861613, -0.02538831034510196, -0.20832381889082585, 0.23057567501216655, -0.10152128395695192, -0.08188682501764284, 0.1286092280156769, 0.22441984194366238, 0.0439716401580674, -0.17810181404030706, 0.015567498862937894, 0.04357120348730042, 0.1756608408899341, 0.10685096099630847, 0.02234332898817367, 0.2010569739335252, 0.17054466362099482, 0.03796314599158801, 0.11782179541202097, -0.1049069078459369, 0.0026394877261541124, -0.22669151344018268, -0.09214095459643845, -0.1792149170069024, -0.00038213737653804164, -0.0208190658979473, -0.1541914608140912, 0.4033609302331328, 0.1613479631457808, 0.14731707846262504, 0.010114320613520479, 0.3853299388046011, 0.11680215982502161, 0.09384985016275763, 0.014238790122650658, 0.2905031513935544, 0.11063063096054652, 0.12052556349825161, -0.2793713873723828, 0.057441028966745244, -0.028341890193368722]
|
1,803.07066
|
Learning Region Features for Object Detection
|
While most steps in the modern object detection methods are learnable, the
region feature extraction step remains largely hand-crafted, featured by RoI
pooling methods. This work proposes a general viewpoint that unifies existing
region feature extraction methods and a novel method that is end-to-end
learnable. The proposed method removes most heuristic choices and outperforms
its RoI pooling counterparts. It moves further towards fully learnable object
detection.
|
cs.CV
|
while most steps in the modern object detection methods are learnable the region feature extraction step remains largely handcrafted featured by roi pooling methods this work proposes a general viewpoint that unifies existing region feature extraction methods and a novel method that is endtoend learnable the proposed method removes most heuristic choices and outperforms its roi pooling counterparts it moves further towards fully learnable object detection
|
[['while', 'most', 'steps', 'in', 'the', 'modern', 'object', 'detection', 'methods', 'are', 'learnable', 'the', 'region', 'feature', 'extraction', 'step', 'remains', 'largely', 'handcrafted', 'featured', 'by', 'roi', 'pooling', 'methods', 'this', 'work', 'proposes', 'a', 'general', 'viewpoint', 'that', 'unifies', 'existing', 'region', 'feature', 'extraction', 'methods', 'and', 'a', 'novel', 'method', 'that', 'is', 'endtoend', 'learnable', 'the', 'proposed', 'method', 'removes', 'most', 'heuristic', 'choices', 'and', 'outperforms', 'its', 'roi', 'pooling', 'counterparts', 'it', 'moves', 'further', 'towards', 'fully', 'learnable', 'object', 'detection']]
|
[-0.025050628718666056, -0.04388069814409722, -0.07399467535486276, 0.002788641832232701, -0.1400416282880487, -0.2725680278628274, 0.021385439322330058, 0.5016229235651818, -0.27924386707882426, -0.26085165182523656, 0.05434752855922632, -0.26012640720882424, -0.2055823413574024, 0.13733332699418746, -0.17790016073330195, 0.09893674138407788, 0.12178614068331874, -0.027477883812301145, -0.10595927997774472, -0.22152342991621204, 0.3035958031488752, 0.07476541833161857, 0.37974322114887676, 0.006651694360753578, 0.163303675071361, -0.041992569363422015, -0.12731564906954934, -0.01987313177210815, -0.040869759728428275, 0.2271925116268297, 0.3438794237533302, 0.2416140749401441, 0.37875195629330294, -0.3408462771242767, -0.27761123226258805, 0.03675670811031578, 0.22838245369987845, 0.12816467268434775, -0.05908286565858306, -0.3232467222225034, 0.08220789214652596, -0.1730145070363175, 0.051845110169696534, -0.16031866445855208, -0.024465387362535253, -0.11873747656830926, -0.250417723461534, 0.06219827170681321, 0.17845473963428626, -0.009389339064276128, -0.0692589774773682, -0.1571629165908124, 0.10239369024268606, 0.10789533061060039, 0.020744055075655608, 0.08536988333798945, 0.2472487727293011, -0.2355231645157222, -0.12739148019163898, 0.31081263664545433, 0.013869913520686554, -0.21526881638618017, 0.17118653068036743, 0.011575493644076314, -0.19113292645973465, 0.1579277099702846, 0.11656623982796163, 0.2439492310072775, -0.16519102369167024, 0.01772399884331125, -0.020144142111706915, 0.20329109908638973, 0.06490227719063335, 0.018035045755272167, 0.19344617578793655, 0.277879925621109, 0.11569161326836118, 0.12218376981433142, -0.20193571967397336, -0.09813535995216983, -0.24482860199570883, -0.05828463629763009, -0.1938970343238025, -0.17013038052104865, -0.07819538765232376, -0.13619868714842154, 0.42620357935965963, 0.24285450378771534, 0.199709396266068, 0.11897560965382692, 0.41958084320085065, 0.03971767508791703, 0.2034958933240198, 0.11982246721868939, 0.22295750144191764, -0.06164594430292985, 0.12367149140812796, -0.10619072890558252, 0.15211598501738274, 0.18328812987910528]
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.