text stringlengths 1 3.65k | source stringlengths 15 79 |
|---|---|
we derive a linear estimate of the signature of positive knots, in terms of their genus. as an application, we show that every knot concordance class contains at most finitely many positive knots. | arxiv:1503.01946 |
the main objective of this article is to develop a matrix pencil approach for the study of the controllability and reachability of a class of linear singular discrete time systems. the description equation of a practical system may be established through selection of the proper state variables. time domain analysis is the method of analyzing the system based on this description equation, through which we may gain a fair understanding of the system ' s structural features as well as its internal properties. using time domain analysis, this article studies the fundamentals in system theory such as reachability and controllability. | arxiv:1406.1489 |
the scalarization of reissner - nordstr \ " { o } m black holes was recently proposed in the einstein - maxwell - scalar theory. here, we show that the appearance of the scalarized reissner - nordstr \ " { o } m black hole is closely related to the gregory - laflamme instability of the reissner - nordstr \ " { o } m black hole without scalar hair. | arxiv:1808.02609 |
we study the integrated sachs - wolfe ( isw ) effect using a model - independent parameterization of the dark energy equation of state. cosmic variance severely restricts the class of models distinguishable from lambda - cdm. in particular if the present value of the equation of state satisfies w _ q ^ o < - 0. 8, the only distinguishable models are those with a rapidly varying equation of state, characterized by a late transition occurring at redshifts z < 3. due to the degeneracy with other cosmological parameters, models with a slowly varying behavior cannot be differentiated from each other or from a cosmological constant using even cosmic variance - limited cmb measurements. this may place a fundamental limit on our understanding of the origin of the presently observed acceleration. | arxiv:astro-ph/0210209 |
we used high resolution spectra acquired at the magellan telescope to measure radial and rotational velocities of approximately 200 stars in the galactic globular cluster ngc 3201. the surveyed sample includes blue stragglers stars ( bsss ) and reference stars in different evolutionary stages ( main sequence turn - off, sub - giant, red giant and asymptotic giant branches ). the average radial velocity value ( $ \ langle v _ r \ rangle = 494. 5 \ pm 0. 5 $ km s $ ^ { - 1 } $ ) confirms a large systemic velocity for this cluster and was used to distinguish 33 residual field interlopers. the final sample of member stars counts 67 bsss and 114 reference stars. similarly to what is found in other clusters, the totality of the reference stars has negligible rotation ( $ < 20 $ km s $ ^ { - 1 } $ ), while the bss rotational velocity distribution shows a long tail extending up to $ \ sim 200 $ km s $ ^ { - 1 } $, with 19 bsss ( out of 67 ) spinning faster than 40 km s $ ^ { - 1 } $. this sets the percentage of fast rotating bsss to $ \ sim 28 \ % $. such a percentage is roughly comparable to that measured in other loose systems ( $ \ omega $ centauri, m4 and m55 ) and significantly larger than that measured in high - density clusters ( as 47 tucanae, ngc 6397, ngc 6752 and m30 ). this evidence supports a scenario where recent bss formation ( mainly from the evolution of binary systems ) is occurring in low - density environments. we also find that the bss rotational velocity tends to decrease for decreasing luminosity and surface temperature, similarly to what is observed in main sequence stars. hence, further investigations are needed to understand the impact of bss internal structure on the observed rotational velocities. | arxiv:2309.01442 |
the fput paradox is the phenomenon whereby a one - dimensional chain of oscillators with nonlinear couplings shows non - ergodic behavior. the trajectory of the system in phase space, with a long wavelength initial condition, closely follows that of the toda model over short times, as both systems seem to relax quickly to a non - thermal, metastable state. over longer times, resonances in the fput spectrum drive the system towards equilibrium, away from the toda trajectory. similar resonances are observed in $ q $ - breather spectra, suggesting that $ q $ - breathers are involved in the route towards thermalization. in this article we investigate such resonances and show that they occur due to exact overlaps of $ q $ - breather frequencies of the type $ m \ omega _ 1 = \ omega _ k $. the resonances appear as peaks in the energy spectrum. further, they give rise to new composite periodic orbits, which exist simultaneously with the original $ q $ - breathers. we find that such resonances are absent in integrable systems, as a consequence of the ( infinite number of ) conservation laws associated with integrability. | arxiv:2406.10790 |
quantum teleportation is a process in which an unknown quantum state is transferred between two spatially separated subspaces of a bipartite quantum system which share an entangled state and communicate classically. in the case of photonic states, this process is probabilistic due to the impossibility of performing a two - particle complete bell state analysis with linear optics. in order to achieve a deterministic teleportation scheme, harnessing other degrees of freedom of a single particle, rather than a third particle, has been proposed. indeed, this leads to a novel type of deterministic teleportation scheme, the so - called hybrid teleportation. here we report the first realization of photonic hybrid quantum teleportation from spin - to - orbital angular momentum degrees of freedom. in our scheme, the polarization state of photon a is transferred to orbital angular momentum of photon b. the teleported states are visualized in real - time by means of an intensified ccd camera. the quality of teleported states is verified by performing quantum state tomography, which confirms an average fidelity higher than 99. 4 %. we believe this experiment paves the route towards a novel way of quantum communication in which encryption and decryption are carried out in naturally different hilbert spaces, and therefore may provide means of enhancing security. | arxiv:1404.7573 |
a mechanism of non - magnetic kondo effect is proposed on the basis of a multiorbital anderson model coupled with dynamical jahn - teller ( jt ) phonons. an electron system coupled dynamically with jt phonons has a vibronic ground state with double degeneracy due to clockwise and anti - clockwise rotational modes with entropy of $ \ log 2 $. when a temperature is lower than a characteristic energy to turn the rotational direction, the rotational degree of freedom is eventually suppressed and the corresponding entropy $ \ log 2 $ is released, leading to quasi - kondo behavior. we discuss possible relevance of this quasi - kondo phenomenon to electronic properties of filled skutterudites. | arxiv:cond-mat/0509473 |
we review recent progress and future prospects for harnessing powerful tools from theoretical high - energy physics, such as scattering amplitudes and effective field theory, to develop a precise and systematically improvable framework for calculating gravitational - wave signals from binary systems composed of black holes and / or neutron stars. this effort aims to provide state - of - the - art predictions that will enable high - precision measurements at future gravitational - wave detectors. in turn, applying the tools of quantum field theory in this new arena will uncover theoretical structures that can transform our understanding of basic phenomena and lead to new tools that will further the cycle of innovation. while still in a nascent stage, this research direction has already derived new analytic results in general relativity, and promises to advance the development of highly accurate waveform models for ever more sensitive detectors. | arxiv:2204.05194 |
we examine the kepler light curves of v1504 cyg and v344 lyr, encompassing ~ 736 d at 1 min cadence. during this span each system exhibited ~ 64 - 65 outbursts, including six superoutbursts. we find that, in both systems, the normal outbursts between two superoutbursts increase in duration over time by a factor ~ 1. 2 - 1. 9, and then reset to a small value after the following superoutburst. in both systems the trend of quiescent intervals between normal outbursts is to increase to a local maximum about half way through the supercycle - the interval from one superoutburst to the next - and then to decrease back to a small value by the time of the next superoutburst. this is inconsistent with osaki ' s thermal - tidal model, which predicts a monotonic increase in the quiescent intervals between normal outbursts during a supercycle. also, most of the normal outbursts have an asymmetric, fast - rise / slower - decline shape, consistent with outbursts triggered at large radii. the exponential rate of decay of the plateau phase of the superoutbursts is 8 d / mag for v1504 cyg and 12 d / mag for v344 lyr. this time scale gives a direct measure of the viscous time scale in the outer accretion disk given the expectation that the entire disk is in the hot, viscous state during superoutburst. the resulting constraint on the shakura - sunyaev parameter, alpha _ { hot } ~ 0. 1, is consistent with the value inferred from the fast dwarf nova decays. by looking at the slow decay rate for superoutbursts, which occur in systems below the period gap, in combination with the slow decay rate in one long outburst above the period gap ( in u gem ), we infer a steep dependence of the decay rate on orbital period for long outbursts. this implies a steep dependence of alpha _ { cold } on orbital period, consistent with tidal torquing as being the dominant angular momentum transport mechanism in quiescent disks in interacting binary systems. | arxiv:1112.4506 |
we review recent theoretical developments about the role of spins, electron - electron interactions, and spin - orbit coupling in metal nanoparticles and semiconductor quantum dots. for a closed system, in the absence of spin - orbit coupling or of an external magnetic field, electron - electron interactions make it possible to have ground states with spin $ s > 1 / 2 $. we review here a theoretical analysis which makes predictions for the probability of finding various values of spin $ s $ for an irregular particle in the limit where the number of electron is large but finite. we also present results for the probability distribution of the spacing between successive groundstate energies in such a particle. in a metallic particle with strong spin - orbit interactions, for odd electron number, the groundstate has a kramers ' degeneracy, which is split linearly by a weak applied magnetic field. the splitting may be characterized by an effective $ g $ - tensor whose principal axes and eigenvalues vary from one level to another. recent calculations have addressed the joint probability distribution, including the anisotropy, of the eigenvalues. the peculiar form of the spin - orbit coupling for a two - dimensional electron system in a gaas heterostructure or quantum well leads to a strong suppression of spin - orbit effects when the electrons are confined in a small quantum dot. spin - effects can be enhanced, however, in the presence of an applied magnetic field parallel to the layer, which may explain recent observations on fluctuations in the conductances through such dots. we also discuss possible explanations for the experimental observations by davidovic and tinkham of a multiplet splitting of the lowest resonance in the tunneling conductance through a gold nano - particle. | arxiv:cond-mat/0109541 |
} : | c 1 | = o ( n 2 3 ) { \ displaystyle | c _ { 1 } | = o ( n ^ { \ frac { 2 } { 3 } } ) } ; supercritical n p > 1 { \ displaystyle np > 1 } : | c 1 | ≈ y n { \ displaystyle | c _ { 1 } | \ approx yn } where y = y ( n p ) { \ displaystyle y = y ( np ) } is the positive solution to the equation e − p n y = 1 − y { \ displaystyle e ^ { - pny } = 1 - y }. the largest connected component has high complexity. all other components are simple and small | c 2 | = o ( log n ) { \ displaystyle | c _ { 2 } | = o ( \ log n ) }. = = = configuration model = = = the configuration model takes a degree sequence or degree distribution ( which subsequently is used to generate a degree sequence ) as the input, and produces randomly connected graphs in all respects other than the degree sequence. this means that for a given choice of the degree sequence, the graph is chosen uniformly at random from the set of all graphs that comply with this degree sequence. the degree k { \ displaystyle k } of a randomly chosen vertex is an independent and identically distributed random variable with integer values. when e [ k 2 ] − 2 e [ k ] > 0 { \ textstyle \ mathbb { e } [ k ^ { 2 } ] - 2 \ mathbb { e } [ k ] > 0 }, the configuration graph contains the giant connected component, which has infinite size. the rest of the components have finite sizes, which can be quantified with the notion of the size distribution. the probability w ( n ) { \ displaystyle w ( n ) } that a randomly sampled node is connected to a component of size n { \ displaystyle n } is given by convolution powers of the degree distribution : w ( n ) = { e [ k ] n − 1 u 1 ∗ n ( n − 2 ), n > 1, u ( 0 ) n = 1, { \ displaystyle w ( n ) = { \ begin { cases } { \ frac { \ mathbb { e } [ k ] } { n - 1 } } u _ { 1 } ^ { * n } ( n - 2 ), & n > 1, \ \ u ( 0 | https://en.wikipedia.org/wiki/Network_science |
the seebeck coefficient $ s $ of the cuprate yba $ _ { 2 } $ cu $ _ { 3 } $ o $ _ { y } $ was measured in magnetic fields large enough to suppress superconductivity, at hole dopings $ p = 0. 11 $ and $ p = 0. 12 $, for heat currents along the $ a $ and $ b $ directions of the orthorhombic crystal structure. for both directions, $ s / t $ decreases and becomes negative at low temperature, a signature that the fermi surface undergoes a reconstruction due to broken translational symmetry. above a clear threshold field, a strong new feature appears in $ s _ { \ rm b } $, for conduction along the $ b $ axis only. we attribute this feature to the onset of 3d - coherent unidirectional charge - density - wave modulations seen by x - ray diffraction, also along the $ b $ axis only. because these modulations have a sharp onset temperature well below the temperature where $ s / t $ starts to drop towards negative values, we infer that they are not the cause of fermi - surface reconstruction. instead, the reconstruction must be caused by the quasi - 2d bidirectional modulations that develop at significantly higher temperature. | arxiv:1704.03829 |
various real - world applications involve modeling complex systems with immense uncertainty and optimizing multiple objectives based on the uncertain model. quantifying the impact of the model uncertainty on the given operational objectives is critical for designing optimal experiments that can most effectively reduce the uncertainty that affect the objectives pertinent to the application at hand. in this paper, we propose the concept of mean multi - objective cost of uncertainty ( multi - objective mocu ) that can be used for objective - based quantification of uncertainty for complex uncertain systems considering multiple operational objectives. we provide several illustrative examples that demonstrate the concept and strengths of the proposed multi - objective mocu. furthermore, we present a real - world example based on the mammalian cell cycle network to demonstrate how the multi - objective mocu can be used for quantifying the operational impact of model uncertainty when there are multiple, possibly competing, objectives. | arxiv:2010.04653 |
a search for highly ionizing particles produced in proton - proton collisions at 8 tev center - of - mass energy is performed by the atlas collaboration at the cern large hadron collider. the dataset used corresponds to an integrated luminosity of 7. 0 fb $ ^ { - 1 } $. a customized trigger significantly increases the sensitivity, permitting a search for such particles with charges and energies beyond what was previously accessible. no events were found in the signal region, leading to production cross section upper limits in the mass range 200 - - 2500 gev for magnetic monopoles with magnetic charge in the range $ 0. 5g _ { d } < | g | < 2. 0g _ { d } $, where $ g _ { d } $ is the dirac charge, and for stable particles with electric charge in the range $ 10 < | z | < 60 $. model - dependent limits are presented in given pair - production scenarios, and model - independent limits are presented in fiducial regions of particle energy and pseudorapidity. | arxiv:1509.08059 |
we consider the class of mathematical programs with orthogonality type constraints ( mpoc ). orthogonality type constraints appear by reformulating the sparsity constraint via auxiliary binary variables and relaxing them afterwards. for mpoc a necessary optimality condition in terms of t - stationarity is stated. the justification of t - stationarity is threefold. first, it allows to capture the global structure of mpoc in terms of morse theory, i. e. deformation and cell - attachment results are established. for that, nondegeneracy for the t - stationary points is introduced and shown to hold at a generic mpoc. second, we prove that karush - kuhn - tucker points of the scholtes - type regularization converge to t - stationary points of mpoc. this is done under the mpoc - tailored linear independence constraint qualification ( licq ), which turns out to be a generic property too. third, we show that t - stationarity applied to the relaxation of sparsity constrained nonlinear optimization ( scno ) naturally leads to its m - stationary points. moreover, we argue that all t - stationary points of this relaxation become degenerate. | arxiv:2110.11793 |
in relation to universale fantastico reverberates in joyce ' s novel, which ends in the middle of a sentence, reasserting vico ' s principle of cyclical history. language, knowledge and society are in a dialectical relationship, which means that any study or comparison of societies must consider the specific contexts of the societies. this has clearly influenced anthropology and sociology. = = see also = = recapitulation theory de nostri temporis studiorum ratione antipositivism historicism sociology of knowledge = = references = = = = further reading = = costelloe, timothy. " giambattista vico ". retrieved 2010 - 09 - 30. kreis, steven. " giambattista vico, the new science ( 1725 ) ". retrieved 2009 - 08 - 03. = = external links = = english translation from 1948 by thomas goddard bergin and max harold fisch is available here [ 1 ]. | https://en.wikipedia.org/wiki/The_New_Science |
understanding cultural phenomena on social networks ( sns ) and exploiting the implicit knowledge about their members is attracting the interest of different research communities both from the academic and the business side. the community of complexity science is devoting significant efforts to define laws, models, and theories, which, based on acquired knowledge, are able to predict future observations ( e. g. success of a product ). in the mean time, the semantic web community aims at engineering a new generation of advanced services by defining constructs, models and methods, adding a semantic layer to sns. in this context, a leapfrog is expected to come from a hybrid approach merging the disciplines above. along this line, this work focuses on the propagation of individual interests in social networks. the proposed framework consists of the following main components : a method to gather information about the members of the social networks ; methods to perform some semantic analysis of the domain of interest ; a procedure to infer members ' interests ; and an interests evolution theory to predict how the interests propagate in the network. as a result, one achieves an analytic tool to measure individual features, such as members ' susceptibilities and authorities. although the approach applies to any type of social network, here it is has been tested against the computer science research community. the dblp ( digital bibliography and library project ) database has been elected as test - case since it provides the most comprehensive list of scientific production in this field. | arxiv:1501.01903 |
the current covid - 19 pandemic has lead to the creation of many corpora that facilitate nlp research and downstream applications to help fight the pandemic. however, most of these corpora are exclusively for english. as the pandemic is a global problem, it is worth creating covid - 19 related datasets for languages other than english. in this paper, we present the first manually - annotated covid - 19 domain - specific dataset for vietnamese. particularly, our dataset is annotated for the named entity recognition ( ner ) task with newly - defined entity types that can be used in other future epidemics. our dataset also contains the largest number of entities compared to existing vietnamese ner datasets. we empirically conduct experiments using strong baselines on our dataset, and find that : automatic vietnamese word segmentation helps improve the ner results and the highest performances are obtained by fine - tuning pre - trained language models where the monolingual model phobert for vietnamese ( nguyen and nguyen, 2020 ) produces higher results than the multilingual model xlm - r ( conneau et al., 2020 ). we publicly release our dataset at : https : / / github. com / vinairesearch / phoner _ covid19 | arxiv:2104.03879 |
we propose a lossy image compression system using the deep - learning autoencoder structure to participate in the challenge on learned image compression ( clic ) 2018. our autoencoder uses the residual blocks with skip connections to reduce the correlation among image pixels and condense the input image into a set of feature maps, a compact representation of the original image. the bit allocation and bitrate control are implemented by using the importance maps and quantizer. the importance maps are generated by a separate neural net in the encoder. the autoencoder and the importance net are trained jointly based on minimizing a weighted sum of mean squared error, ms - ssim, and a rate estimate. our aim is to produce reconstructed images with good subjective quality subject to the 0. 15 bits - per - pixel constraint. | arxiv:1902.07385 |
we study the boundedness of the $ h ^ { \ infty } $ functional calculus for differential operators acting in ( l ^ { p } ( \ mathbb { r } ^ { n } ; \ mathbb { c } ^ { n } ) ). for constant coefficients, we give simple conditions on the symbols implying such boundedness. for non - constant coefficients, we extend our recent results for the ( l ^ p ) theory of the kato square root problem to the more general framework of hodge - dirac operators with variable coefficients ( \ pi _ b ) as treated in ( l ^ 2 ( \ mathbb { r } ^ { n } ; \ mathbb { c } ^ { n } ) ) by axelsson, keith, and mcintosh. we obtain a characterization of the property that ( \ pi _ b ) has a bounded ( h ^ { \ infty } ) functional calculus, in terms of randomized boundedness conditions of its resolvent. this allows us to deduce stability under small perturbations of this functional calculus. | arxiv:0907.2274 |
the past decade has witnessed a growing interest in lunar exploration missions. the autonomy of lunar surface and in - orbit missions is, however, dependent on accurate and instantaneous navigation services. these services can not be provided by current global navigation satellite systems ( gnss ) whose signals suffer from poor geometry and coverage in the vicinity of the moon. preliminary results of a systems architecture study on a new satellite navigation system orbiting the moon are presented. lunar frozen orbit conditions under j2, c22 and third - body perturbations are assumed. the formulation includes the following design decisions : ( 1 ) orbit semi - major axis, ( 2 ) number of satellites, ( 3 ) number of orbital planes, ( 4 ) satellite phasing in adjacent planes, ( 5 ) orbit eccentricity and ( 6 ) argument of periapsis. the borg multi - objective evolutionary algorithm ( moea ) framework is used to optimize the satellite constellation design problem, with a fitness function that takes into account performance, cost, availability and station - keeping deltav. the performance metric is based on the geometric dilution of precision ( gdop ), which is computed over a grid of 500 equidistant points on the lunar surface. additionally, the input satellite orbits used in the gdop computation are obtained from high - fidelity orbit propagation using nasa general mission analysis toolbox. finally, satellite costs are based on satellite dry mass estimates derived from the power budget analysis assuming a satellite lifetime of 10 years. results show that lunar gnss constellation with 20 satellites at frozen orbits can achieve satisfactory performance at mid - latitudes but not at the poles. | arxiv:2010.08706 |
as two mainstream frameworks in federated learning ( fl ), both centralized and decentralized approaches have shown great application value in practical scenarios. however, existing studies do not provide sufficient evidence and clear guidance for analysis of which performs better in the fl community. although decentralized methods have been proven to approach the comparable convergence of centralized with less communication, their test performance always falls short of expectations in empirical studies. to comprehensively and fairly compare their efficiency gaps in fl, in this paper, we explore their stability and generalization efficiency. specifically, we prove that on the general smooth non - convex objectives, 1 ) centralized fl ( cfl ) always generalizes better than decentralized fl ( dfl ) ; 2 ) cfl achieves the best performance via adopting partial participation instead of full participation ; and, 3 ) there is a necessary requirement for the topology in dfl to avoid performance collapse as the training scale increases. we also conduct extensive experiments on several common setups in fl to validate that our theoretical analysis is consistent with experimental phenomena and contextually valid in several general and practical scenarios. | arxiv:2310.03461 |
sporting events are extremely complex and require a multitude of metrics to accurate describe the event. when making multiple predictions, one should make them from a single source to keep consistency across the predictions. we present a multi - task learning method of generating multiple predictions for analysis via a single prediction source. to enable this approach, we utilize a fine - grain representation using fine - grain spatial data using a wide - and - deep learning approach. additionally, our approach can predict distributions rather than single point values. we highlighted the utility of our approach on the sport of rugby league and call our prediction engine " rugby - bot ". | arxiv:1910.07410 |
in this paper, new stability analysis methods are proposed for digital robust motion control systems implemented using a disturbance observer. | arxiv:2502.00683 |
we analyse proton decay in the context of simple supersymmetric su ( 5 ) grand unified models with an extra compact spatial dimension described by the orbifold s ^ 1 / ( z _ 2 x z _ 2 ' ). gauge and higgs degrees of freedom live in the bulk, while matter fields can only live at the fixed point branes. we present an extended discussion of matter interactions on the brane. we show that proton decay is naturally suppressed or even forbidden by suitable implementations of the parity symmetries on the brane. the corresponding mechanism does not affect the su ( 5 ) description of fermion masses also including the neutrino sector, where majorana mass terms remain allowed. | arxiv:hep-ph/0102301 |
in this article we obtain new irrationality measures for values of functions which belong to a certain class of hypergeometric functions including shifted logarithmic functions, binomial functions and shifted exponential functions. we explicitly construct pad \ ' e approximations by using a formal method and show that the associated sequences satisfy a poincar \ ' e - type recurrence. to study precisely the asymptotic behavior of those sequences, we establish an \ emph { effective } version of the poincar \ ' e - perron theorem. as a consequence we obtain, among others, effective irrationality measures for values of binomial functions at rational numbers, which might have useful arithmetic applications. a general theorem on simultaneous rational approximations that we need is proven by using new arguments relying on parametric geometry of numbers. | arxiv:2202.10782 |
in - context learning ( icl ) performs tasks by prompting a large language model ( llm ) using an instruction and a small set of annotated examples called demonstrations. recent work has shown that precise details of the inputs used in the icl prompt significantly impact performance, which has incentivized instruction selection algorithms. the effect of instruction - choice however is severely underexplored, with existing analyses restricted to shallow subsets of models and tasks, limiting the generalizability of their insights. we develop instructeval, an icl evaluation suite to conduct a thorough assessment of these techniques. the suite includes 13 open - sourced llms of varying scales from four model families, and covers nine tasks across three categories. using the suite, we evaluate the relative performance of seven popular instruction selection methods over five metrics relevant to icl. our experiments reveal that using curated manually - written instructions or simple instructions without any task - specific descriptions often elicits superior icl performance overall than that of automatic instruction - induction methods, pointing to a lack of generalizability among the latter. we release our evaluation suite for benchmarking instruction selection approaches and enabling more generalizable methods in this space. | arxiv:2307.00259 |
we investigate the problem of estimating geodesic tortuosity and constrictivity as two structural characteristics of stationary random closed sets. they are of central importance for the analysis of effective transport properties in porous or composite materials. loosely speaking, geodesic tortuosity measures the windedness of paths whereas the notion of constrictivity captures the appearance of bottlenecks resulting from narrow passages within a given materials phase. we first provide mathematically precise definitions of these quantities and introduce appropriate estimators. then, we show strong consistency of these estimators for unboundedly growing sampling windows. in order to apply our estimators to real datasets, the extent of edge effects needs to be controlled. this is illustrated using a model for a multi - phase material that is incorporated in solid oxid fuel cells. | arxiv:1804.02218 |
our previous paper describes a geometric translation of the construction of open gromov - witten invariants by j. solomon and s. tukachinsky from a perspective of $ a _ { \ infty } $ - algebras of differential forms. we now use this geometric perspective to show that these invariants reduce to welschinger ' s open gromov - witten invariants in dimension 6, inline with their and g. tian ' s expectations. as an immediate corollary, we obtain a translation of solomon - tukachinsky ' s open wdvv equations into relations for welschinger ' s invariants. | arxiv:1912.05437 |
a new cosmological model leads to testable predictions that are different from those of both standard cosmology and models with a cosmological constant. the prediction that q _ 0 = 0 is the same as in other ` ` coasting universe ' ' models, but arises without the need for any exotic form of matter or other ad hoc assumptions. | arxiv:hep-th/9807141 |
the quantum approximate optimization algorithm ( qaoa ) is a promising variational algorithm for solving combinatorial optimization problems on near - term devices. however, as the number of layers in a qaoa circuit increases, which is correlated with the quality of the solution, the number of parameters to optimize grows linearly. this results in more iterations required by the classical optimizer, which results in an increasing computational burden as more circuit executions are needed. to mitigate this issue, we introduce qaoa - pca, a novel reparameterization technique that employs principal component analysis ( pca ) to reduce the dimensionality of the qaoa parameter space. by extracting principal components from optimized parameters of smaller problem instances, qaoa - pca facilitates efficient optimization with fewer parameters on larger instances. our empirical evaluation on the prominent maxcut problem demonstrates that qaoa - pca consistently requires fewer iterations than standard qaoa, achieving substantial efficiency gains. while this comes at the cost of a slight reduction in approximation ratio compared to qaoa with the same number of layers, qaoa - pca almost always outperforms standard qaoa when matched by parameter count. qaoa - pca strikes a favorable balance between efficiency and performance, reducing optimization overhead without significantly compromising solution quality. | arxiv:2504.16755 |
a general prescription for constructing quasi - local conserved quantities in general relativity is proposed. the construction is applied to bms symmetry generators in newman - unti gauge, so as to define quasi - local bms charges. it is argued that the zero mode of this bms charge is a promising definition of quasi - local energy. | arxiv:1908.07504 |
two - place nonlocal systems have attracted many scientists ' attentions. in this paper, two - place non - localities are extended to multi - place non - localities. especially, various two - place and four - place nonlocal nonlinear schrodinger ( nls ) systems and kadomtsev - petviashvili ( kp ) equations are systematically obtained from the discrete symmetry reductions of the coupled local systems. the lax pairs for the two - place and four - place nonlocal nls and kp equations are explicitly given. some types of exact solutions especially the multiple soliton solutions for two - place and four - place kp equations are investigated by means of the group symmetric - antisymmetric separation approach. | arxiv:1901.02828 |
we explore phenomenological signatures of light quark jet quenching within the ads / cft correspondence. numerical studies of the instantaneous energy loss of light quarks, modeled as falling strings, suggest a linear path dependence. we propose a phenomenological model for the energy loss and use it to compute the nuclear modification factor $ r _ { aa } $ for light quarks in an expanding plasma with glauber initial conditions. the results are compared to the light hadron $ r _ { aa } $ data at the lhc and, although they show qualitative agreement, the quantitative disagreement we found motivated the exploration of effects from higher order derivative corrections to $ ads _ 5 $ on this observable. | arxiv:1208.0305 |
let a be an arrangement of complex hyperplanes. the fundamental group of the complement of a is determined by a braid monodromy homomorphism from a finitely generated free group to the pure braid group. using the gassner representation of the pure braid group, we find an explicit presentation for the alexander invariant of a. from this presentation, we obtain combinatorial lower bounds for the ranks of the chen groups of a. we also provide a combinatorial criterion for when these lower bounds are attained. | arxiv:alg-geom/9703030 |
obvious strategyproofness ( osp ) is an appealing concept as it allows to maintain incentive compatibility even in the presence of agents that are not fully rational, e. g., those who struggle with contingent reasoning [ li, 2015 ]. however, it has been shown to impose some limitations, e. g., no osp mechanism can return a stable matching [ ashlagi and gonczarowski, 2015 ]. we here deepen the study of the limitations of osp mechanisms by looking at their approximation guarantees for basic optimization problems paradigmatic of the area, i. e., machine scheduling and facility location. we prove a number of bounds on the approximation guarantee of osp mechanisms, which show that osp can come at a significant cost. however, rather surprisingly, we prove that osp mechanisms can return optimal solutions when they use monitoring - - a novel mechanism design paradigm that introduces a mild level of scrutiny on agents ' declarations [ kovacs et al., 2015 ]. | arxiv:1702.05640 |
according to recent works [ tsui pss \ textbf { 55 }, 237 - 242 ( 2007 ), \ textbf { 55 }, 2042 - 2044 ( 2007 ) ], the neptune adams ring main arc fraternite is regarded as captured by the corotation elliptic resonance ( cer ) potential of galatea. the minor arcs egalite ( 2, 1 ), liberte, and courage are located at positions where the time averaged forces, due to the 42 - 43 corotation - lindblad resonances under the central field of neptune, vanish. with adequately chosen fraternite mass and galatea eccentricity, this model gives minor arc locations compatible to observed positions, and allows a dynamic transport of materials among arcs. to complement this model, the effect of self - gravity of fraternite, with a distributed mass, is evaluated together with the cer potential to account for its $ 10 ^ { 0 } $ longitudinal span. although self - gravity is the collective action of all the particles in the arc, each individual particle will see the self - potential with a central maximum as an external potential generated by other particles. | arxiv:0905.2888 |
the local position invariance ( lpi ) is one of the three major pillars of einstein equivalence principle, ensuring the space - time independence on the outcomes of local experiments. the lpi has been tested by measuring the gravitational redshift effect in various depths of gravitational potentials. we propose a new cosmological test of the lpi by observing the asymmetry in the cross - correlation function between different types of galaxies, which predominantly arises from the gravitational redshift effect induced by the gravitational potential of halos at which the galaxies reside. we show that the ongoing and upcoming galaxy surveys can give a fruitful constraint on the lpi - violating parameter, $ \ alpha $, at distant universes ( redshift $ z \ sim0. 1 - 1. 8 $ ) over the cosmological scales ( separation $ s \ sim5 - 10 \, { \ rm mpc } / h $ ) that have not yet been explored, finding that the expected upper limit on $ \ alpha $ can reach $ 0. 03 $. | arxiv:2112.07727 |
we argue that the vacuum of quantum gravity must contain a hierarchical structure of correlations spanning all length scales. these correlated domains ( called ` vecros ' ) correspond to virtual fluctuations of black hole microstates. larger fluctuations are suppressed by their larger action, but this suppression is offset by a correspondingly larger phase space of possible configurations. we give an explicit lattice model of these vecro fluctuations, noting how their distribution changes as the gravitational pull of a star becomes stronger. at the threshold of formation of a closed trapped surface, these virtual fluctuations transition into on - shell black hole microstates ( fuzzballs ). fuzzballs radiate from their surface like normal bodies, resolving the information paradox. we also argue that any model without vecro - type extended vacuum correlations cannot resolve the paradox. | arxiv:2405.08945 |
in this note we study a nonlocal version of the sobolev inequality \ begin { equation * } \ int _ { \ mathbb { r } ^ n } | \ nabla u | ^ 2 dx \ geq s _ { hls } \ left ( \ int _ { \ mathbb { r } ^ n } \ big ( | x | ^ { - \ alpha } \ ast u ^ { 2 _ \ alpha ^ { \ ast } } \ big ) u ^ { 2 _ \ alpha ^ { \ ast } } dx \ right ) ^ { \ frac { 1 } { 2 _ \ alpha ^ { \ ast } } }, \ quad \ forall u \ in \ mathcal { d } ^ { 1, 2 } ( \ mathbb { r } ^ n ), \ end { equation * } where $ s _ { hls } $ is the best constant, $ \ ast $ denotes the standard convolution and $ \ mathcal { d } ^ { 1, 2 } ( \ mathbb { r } ^ n ) $ denotes the classical sobolev space with respect to the norm $ \ | u \ | _ { \ mathcal { d } ^ { 1, 2 } ( \ mathbb { r } ^ n ) } = \ | \ nabla u \ | _ { l ^ 2 ( \ mathbb { r } ^ n ) } $. by using the nondegeneracy property of the extremal functions, we prove that the existence of the gradient type remainder term and a reminder term in the weak $ l ^ { \ frac { n } { n - 2 } } $ - norm of above inequality for all $ 0 < \ alpha < n $. | arxiv:2305.16857 |
the gromov - - wasserstein problem is a non - convex optimization problem over the polytope of transportation plans between two probability measures supported on two spaces, each equipped with a cost function evaluating similarities between points. akin to the standard optimal transportation problem, it is natural to ask for conditions guaranteeing some structure on the optimizers, for instance if these are induced by a ( monge ) map. we study this question in euclidean spaces when the cost functions are either given by ( i ) inner products or ( ii ) squared distances, two standard choices in the literature. we establish the existence of an optimal map in case ( i ) and of an optimal 2 - map ( the union of the graphs of two maps ) in case ( ii ), both under an absolute continuity condition on the source measure. additionally, in case ( ii ) and in dimension one, we numerically design situations where optimizers of the gromov - - wasserstein problem are 2 - maps but are not maps. this suggests that our result cannot be improved in general for this cost. still in dimension one, we additionally establish the optimality of monotone maps under some conditions on the measures, thereby giving insight on why such maps often appear to be optimal in numerical experiments. | arxiv:2210.11945 |
in the usual entanglement detection scenario the possible measurements and the corresponding data are assumed to be fully characterized. we consider the situation where the measurements are known, but the data is scrambled, meaning the assignment of the probabilities to the measurement outcomes is unknown. we investigate in detail the two - qubit scenario with local measurements in two mutually unbiased bases. first, we discuss the use of entropies to detect entanglement from scrambled data, showing that tsallis - and r \ ' enyi entropies can detect entanglement in our scenario, while the shannon entropy cannot. then, we introduce and discuss scrambling - invariant families of entanglement witnesses. finally, we show that the set of non - detectable states in our scenario is non - convex and therefore in general hard to characterize. | arxiv:1901.07946 |
we study a $ u ( n ) $ - invariant vector + matrix chain with the color structure of a lattice gauge theory with quarks and interpret it as a theory of open andclosed strings with target space $ \ z $. the string field theory is constructed as a quasiclassical expansion for the wilson loops and lines in this model. in a particular parametrization this is a theory of two scalar massless fields defined in the half - space $ \ { x \ in \ z, \ tau > 0 \ } $. the extra dimension $ \ tau $ is related to the longitudinal mode of the strings. the topology - changing string interactions are described by a local potential. the closed string interaction is nonzero only at boundary $ \ tau = 0 $ while the open string interaction falls exponentially with $ \ tau $. | arxiv:hep-th/9410164 |
large language models ( llms ) have shown significant abilities in retrieving medical knowledge, reasoning over it and answering medical questions comparably to physicians. however, these models are not interpretable, hallucinate, are difficult to maintain and require enormous compute resources for training and inference. in this paper, we report results from gyan, an explainable language model based on an alternative architecture, on the pubmedqa data set. the gyan llm is a compositional language model and the model is decoupled from knowledge. gyan is trustable, transparent, does not hallucinate and does not require significant training or compute resources. gyan is easily transferable across domains. gyan - 4. 3 achieves sota results on pubmedqa with 87. 1 % accuracy compared to 82 % by medprompt based on gpt - 4 and 81. 8 % by med - palm 2 ( google and deepmind ). we will be reporting results for other medical data sets - medqa, medmcqa, mmlu - medicine in the future. | arxiv:2504.05074 |
focus is given on the macroscopic and microscopic experimental works realized during a decade on the clear case of itinerant metamagnetism in the heavy fermion paramagnetic compound ceru2si2. emphasis is made on the feedback between the band structure, the exchange coupling and the lattice instability. sweeps in magnetic field, pressure and temperature feel the pseudogap of this strongly correlated electronic system as well as its equivalent ceru2ge2 at a fictitious negative pressure. some mysteries persist as the complete observation of the fs above the metamagnetic field hm and the detection of the dynamical ferromagnetic fluctuation near hm. the novelty of the bilayer ruthenate sr3ru2o7 is discussed by comparison. despite differences in spin and electronic dimensionality many common trends emerge. | arxiv:cond-mat/0203462 |
in this paper, we consider a cosmological model in $ f ( r, g ) $ gravity in a flat space - time, where $ r $ is the ricci scalar and $ g $ is the gauss - bonnet invariant. the function $ f ( r, g ) $ is taken as a linear combination of $ r $ and an exponential function of $ g $. we analyze the observational constraints under a power law cosmology which depends on two physical parameters : the hubble constant $ h _ 0 $ and the deceleration parameter $ q $. we constrain these two dependent parameters using the latest 77 points of the ohd data, 1048 points of the pantheon data, and the joint data ohd + pantheon and compare the results with the $ \ lambda $ cdm. also, we speculate constraints using a simulated data set for the future jdem ( joint dark energy mission ) / omega, supernovae survey. we see that $ h _ 0 $ is in very close agreement with some of the latest results from the planck collaboration that assume the $ \ lambda $ cdm model. our work in power law cosmology better fits the pantheon data than the earlier analysis \ cite { kumar : 2011sw, rani : 2014sia }. however, the constraints obtained on $ h $ average, $ < h _ 0 > $ and $ q $ average, $ < q > $ using the simulated data set for the future jdem / omega, supernovae survey are found to be inconsistent with the values obtained from the ohd and the pantheon data. additionally, we discuss statefinder diagnostics and see that the power law models approach the standard $ \ lambda $ cdm model ( $ q \ rightarrow - 1 $ ). this model satisfies the generalized second law of thermodynamics. finally, we conclude that the power law cosmology in $ f ( r, g ) $ gravity explains most of the distinguished attributes of evolution in cosmology. | arxiv:2304.09917 |
the magnetic field of the classical t tauri star v2129 oph can be modeled approximately by superposing slightly tilted dipole and octupole moments, with polar magnetic field strengths of 0. 35kg and 1. 2kg respectively ( donati et al. 2007 ). here we construct a numerical model of v2129 oph incorporating this result and simulate accretion onto the star. simulations show that the disk is truncated by the dipole component and matter flows towards the star in two funnel streams. closer to the star, the flow is redirected by the octupolar component, with some of the matter flowing towards the high - latitude poles, and the rest into the octupolar belts. the shape and position of the spots differ from those in a pure dipole case, where crescent - shaped spots are observed at the intermediate latitudes. simulations show that if the disk is truncated at the distance of 6. 2 r _ * which is comparable with the co - rotation radius, 6. 8 r _ *, then the high - latitude polar spots dominate, but the accretion rate obtained from the simulations is about an order of magnitude lower than the observed one. the accretion rate matches the observed one if the disk is disrupted much closer to the star, at 3. 4 r _ *. however, the octupolar belt spots strongly dominate. better match has been obtained in experiments with a dipole field twice as strong. the torque on the star from the disk - magnetosphere interaction is small, and the time - scale of spin evolution, 2 x10 ^ 7 - 10 ^ 9 years is longer than the 2x10 ^ 6 years age of v2129 oph. the external magnetic flux of the star is strongly influenced by the disk : the field lines connecting the disk and the star inflate and form magnetic towers above and below the disk. the potential ( vacuum ) approximation is still valid inside the alfv \ ' en ( magnetospheric ) surface where the magnetic stress dominates over the matter stress. | arxiv:0912.1681 |
we investigate front propagation in systems with diffusive and sub - diffusive behavior. the scaling behavior of moments of the diffusive problem, both in the standard and in the anomalous cases, is not enough to determine the features of the reactive front. in fact, the shape of the bulk of the probability distribution of the transport process, which determines the diffusive properties, is important just for pre - asymptotic behavior of front propagation, while the precise shape of the tails of the probability distribution determines asymptotic behavior of front propagation. | arxiv:1609.01180 |
real - life mobile phone data may contain noisy instances, which is a fundamental issue for building a prediction model with many potential negative consequences. the complexity of the inferred model may increase, may arise overfitting problem, and thereby the overall prediction accuracy of the model may decrease. in this paper, we address these issues and present a robust prediction model for real - life mobile phone data of individual users, in order to improve the prediction accuracy of the model. in our robust model, we first effectively identify and eliminate the noisy instances from the training dataset by determining a dynamic noise threshold using naive bayes classifier and laplace estimator, which may differ from user - to - user according to their unique behavioral patterns. after that, we employ the most popular rule - based machine learning classification technique, i. e., decision tree, on the noise - free quality dataset to build the prediction model. experimental results on the real - life mobile phone datasets ( e. g., phone call log ) of individual mobile phone users, show the effectiveness of our robust model in terms of precision, recall and f - measure. | arxiv:1902.07588 |
traditional semi - supervised learning uses only labeled instances to train a classifier and then this classifier is utilized to classify unlabeled instances, while sometimes there are only positive instances which are elements of the target concept are available in the labeled set. our research in this paper the design of learning algorithms from positive and unlabeled instances only. among all the semi - supervised positive and unlabeled learning methods, it is a fundamental step to extract useful information from unlabeled instances. in this paper, we design a novel framework to take advantage of valid information in unlabeled instances. in essence, this framework mainly includes that ( 1 ) selects reliable negative instances through the fuzziness of the instances ; ( 2 ) chooses new positive instances based on the fuzziness of the instances to expand the initial positive set, and we named these new instances as reliable positive instances ; ( 3 ) uses data editing technique to filter out noise points with high fuzziness. the effectiveness of the presented algorithm is verified by comparative experiments on uci dataset. | arxiv:1903.11064 |
we present a study of the properties of bargmann invariants ( bi ) and null phase curves ( npc ) in the theory of the geometric phase for finite dimensional systems. a recent suggestion to exploit the majorana theorem on symmetric su ( 2 ) multispinors is combined with the schwinger oscillator operator construction to develop efficient operator based methods to handle these problems. the bi is described using intrinsic unitary invariant angle parameters, whose algebraic properties as functions of hilbert space dimension are analysed using elegant group theoretic methods. the bi - geometric phase connection, extended by the use of npc ' s, is explored in detail, and interesting new experiments in this subject are pointed out. | arxiv:1908.03325 |
a simple one - dimensional microscopic model of the depinning transition of an interface from an attractive hard wall is introduced and investigated. upon varying a control parameter, the critical behaviour observed along the transition line changes from a directed - percolation to a multiplicative - noise type. numerical simulations allow for a quantitative study of the multicritical point separating the two regions, mean - field arguments and the mapping on a yet simpler model provide some further insight on the overall scenario. | arxiv:cond-mat/0302588 |
actor - critic algorithms learn an explicit policy ( actor ), and an accompanying value function ( critic ). the actor performs actions in the environment, while the critic evaluates the actor ' s current policy. however, despite their stability and promising convergence properties, current actor - critic algorithms do not outperform critic - only ones in practice. we believe that the fact that the critic learns q ^ pi, instead of the optimal q - function q *, prevents state - of - the - art robust and sample - efficient off - policy learning algorithms from being used. in this paper, we propose an elegant solution, the actor - advisor architecture, in which a policy gradient actor learns from unbiased monte - carlo returns, while being shaped ( or advised ) by the softmax policy arising from an off - policy critic. the critic can be learned independently from the actor, using any state - of - the - art algorithm. being advised by a high - quality critic, the actor quickly and robustly learns the task, while its use of the monte - carlo return helps overcome any bias the critic may have. in addition to a new actor - critic formulation, the actor - advisor, a method that allows an external advisory policy to shape a policy gradient actor, can be applied to many other domains. by varying the source of advice, we demonstrate the wide applicability of the actor - advisor to three other important subfields of rl : safe rl with backup policies, efficient leverage of domain knowledge, and transfer learning in rl. our experimental results demonstrate the benefits of the actor - advisor compared to state - of - the - art actor - critic methods, illustrate its applicability to the three other application scenarios listed above, and show that many important challenges of rl can now be solved using a single elegant solution. | arxiv:1902.02556 |
we consider the problem of showing that 1 is an eigenvalue for a family of generalised transfer operators of the farey map. this problem is related to the spectral theory of the modular surface via the selberg zeta function and the theory of dynamical zeta functions of maps. after briefly recalling these connections, we show that the problem can be formulated for operators on an appropriate hilbert space and translated into a linear algebra problem for infinite matrices. | arxiv:2211.11664 |
the ground - state energy of a three - dimensional polaron gas in a magnetic field is investigated. an upper bound for the ground - state energy is derived within a variational approach which is based on a many - body generalization of the lee - low - pines transformation. the basic contributing ingredients found are the ground - state energy and the static structure factor of the homogeneous electron gas in a magnetic field. both these quantities are derived in the hartree - fock approximation. the resulting ground - state energy of the polaron gas is analyzed as a function of the electron density and of the magnetic field strength. | arxiv:cond-mat/0602050 |
we construct a spatial indexing solution for the highly constrained environment of an in - vehicle unit in a distributed vehicle tolling scheme based on satellite navigation ( gnss ). we show that an immutable, purely functional implementation of a high - fanout quadtree is a simple, practical solution that satisfies all the requirements of such a system. | arxiv:1408.0114 |
in this article, we consider the quasi - linear stochastic wave and heat equations on the real line and with an additive gaussian noise which is white in time and behaves in space like a fractional brownian motion with hurst index $ h \ in ( 0, 1 ) $. the drift term is assumed to be globally lipschitz. we prove that the solution of each of the above equations is continuous in terms of the index $ h $, with respect to the convergence in law in the space of continuous functions. | arxiv:1810.03692 |
we show that holographic models of qcd predict the presence of a chern - simons coupling between vector and axial - vector mesons at finite baryon density. in the ads / cft dictionary, the coefficient of this coupling is proportional to the baryon number density, and is fixed uniquely in the five - dimensional holographic dual by anomalies in the flavor currents. for the lightest mesons, the coupling mixes transverse $ \ rho $ and $ a _ 1 $ polarization states. at sufficiently large baryon number densities, it produces an instability, which causes the $ \ rho $ and $ a _ 1 $ mesons to condense in a state breaking both rotational and translational invariance. | arxiv:0704.1604 |
spin - phonon interactions are central to many interesting phenomena, ranging from superconductivity to magnetoelectric effects. yet, they are believed to have a negligible influence on the structural behavior of most materials. for example, magnetic perovskite oxides often undergo structural transitions accompanied by magnetic signatures whose minuteness suggests that the underlying spin - phonon couplings are largely irrelevant. here we present an exception to this rule, showing that novel effects can occur as a consequence. our first - principles calculations reveal that spin - phonon interactions are essential to reproduce the experimental observations on the phase diagram of magnetoelectric multiferroic bicoo $ _ { 3 } $. moreover, we predict that, under compression, these couplings lead to an unprecedented temperature - driven double - reentrant sequence of ferroelectric transitions. we propose how to modify bicoo $ _ { 3 } $ via chemical doping to reproduce such striking effects at ambient conditions, thereby yielding useful multifunctionality. | arxiv:1612.04356 |
we consider a class of boussinesq systems of bona - smith type in two space dimensions approximating surface wave flows modelled by the three - dimensional euler equations. we show that various initial - boundary - value problems for these systems, posed on a bounded plane domain are well posed locally in time. in the case of reflective boundary conditions, the systems are discretized by a modified galerkin method which is proved to converge in $ l ^ 2 $ at an optimal rate. numerical experiments are presented with the aim of simulating two - dimensional surface waves in complex plane domains with a variety of initial and boundary conditions, and comparing numerical solutions of bona - smith systems with analogous solutions of the bbm - bbm system. | arxiv:0907.4918 |
we obtain schauder estimates for a general class of linear integro - differential equations. the estimates are applied to a scalar non - local burgers equation and complete the global well - posedness results obtained in \ cite { isv }. | arxiv:1604.07377 |
quantum logic was introduced in 1936 by garrett birkhoff and john von neumann as a framework for capturing the logical peculiarities of quantum observables. it generalizes, and on 1 - dimensional hilbert space coincides with, boolean propositional logic. we introduce the weak and strong satisfiability problem for quantum logic terms. it turns out that in dimension two both are also np - complete. for higher - dimensional spaces r ^ d and c ^ d with d > 2 fixed, on the other hand, we show both problems to be complete for the nondeterministic blum - shub - smale model of real computation. this provides a unified view on both turing and real bss complexity theory ; and extends the still relatively scarce family of np _ r - complete problems with one perhaps closest in spirit to the classical cook - levin theorem. our investigations on the dimensions a term is weakly / strongly satisfiable in lead to satisfiability problems in indefinite finite and finally in infinite dimension. here, strong satisfiability turns out as polynomial - time equivalent to the feasibility of noncommutative integer polynomial equations | arxiv:1004.1696 |
we show how to use matrix methods of quantum mechanics to efficiently and accurately calculate axially symmetric radiation transfer in clouds, with conservative scattering of arbitrary anisotropy. analyses of conservative scattering, where the single scattering albedo is $ \ tilde \ omega = 1 $ and no energy is exchanged between the radiation and scatterers, began with work by schwarzschild, milne, eddington and others on radiative transfer in stars. there the scattering is isotropic or nearly so. it has been difficult to extend traditional methods to highly anisotropic scattering, like that of sunlight in earth ' s clouds. the $ 2n $ - stream method described here is a practical way to handle highly anisotropic, conservative scattering. the basic ideas of the $ 2n $ - stream method are an extension of wick ' s seminal work on transport of thermal neutrons by isotropic scattering to scattering with arbitrary anisotropy. how to do this for finite absorption and $ \ tilde \ omega < 1 $ was described in our previous paper ( arxiv : 2205. 09713v2 ). but those methods fail for conservative scattering, when $ \ tilde \ omega = 1 $. here we show that minor modifications to the fundamental $ 2n $ - scattering theory for $ \ tilde \ omega < 1 $ make it suitable for $ \ tilde \ omega = 1 $. | arxiv:2207.03978 |
we consider the determinantal point processes associated with the spectral projectors of a schr \ " odinger operator on $ \ mathbb { r } $, with a smooth confining potential. in the semiclassical limit, where the number of particles tends to infinity, we obtain a szeg \ h { o } - type central limit theorem ( clt ) for the fluctuations of smooth linear statistics. more precisely, the laplace transform of any statistic converges without renormalization to a gaussian limit with a $ h ^ { 1 / 2 } $ - type variance, which depends on the potential. in the one - well ( one - cut ) case, using the quantum action - angle theorem and additional micro - local tools, we reduce the problem to the asymptotics of fredholm determinants of certain approximately toeplitz operators. in the multi - cut case, we show that for generic potentials, a similar result holds and the contributions of each wells are independent in the limit. | arxiv:2304.12275 |
we utilize the alma - manga quench and star formation ( almaquest ) survey to investigate the kpc - scale scaling relations, presented as the resolved star forming main sequence ( rsfms : $ \ sigma _ { \ rm sfr } $ vs. $ \ sigma _ { * } $ ), the resolved schmidt - kennicutt relation ( rsk : $ \ sigma _ { \ rm sfr } $ vs. $ \ sigma _ { \ rm h _ { 2 } } $ ), and the resolved molecular gas main sequence ( rmgms : $ \ sigma _ { \ rm h _ { 2 } } $ vs. $ \ sigma _ { * } $ ), for 11478 star - forming and 1414 retired spaxels ( oversampled by a factor of $ \ sim20 $ ) located in 22 green valley ( gv ) and 12 main sequence ( ms ) galaxies. for a given galaxy type ( ms or gv ), the retired spaxels are found to be offset from the sequences formed by the star - forming spaxels on the rsfms, rsk, and rmgms planes, toward lower absolute values of ssfr, sfe, and $ f _ { \ rm h _ { 2 } } $ by $ \ sim $ 1. 1, 0. 6, and 0. 5 dex. the scaling relations for gv galaxies are found to be distinct from that of the ms galaxies, even if the analyses are restricted to the star - forming spaxels only. it is found that for star - forming spaxels, ssfr, sfe, and $ f _ { \ rm h _ { 2 } } $ in gv galaxies are reduced by $ \ sim $ 0. 36, 0. 14, and 0. 21 dex, respectively, compared to those in ms galaxies. therefore, the suppressed ssfr / sfe / $ f _ { \ rm h _ { 2 } } $ in gv galaxies are associated with not only an increased proportion of retired regions in gv galaxies but also a depletion of these quantities in star - forming regions. finally, the reduction of sfe and $ f _ { \ rm h _ { 2 } } $ in gv galaxies relative to ms galaxies is seen in both bulge and disk regions ( albeit with larger uncertainties ), suggesting that statistically, quenching in the gv population may persist from the inner to the outer regions. | arxiv:2201.05318 |
machine learning enables extracting clinical insights from large temporal datasets. the applications of such machine learning models include identifying disease patterns and predicting patient outcomes. however, limited interpretability poses challenges for deploying advanced machine learning in digital healthcare. understanding the meaning of latent states is crucial for interpreting machine learning models, assuming they capture underlying patterns. in this paper, we present a concise algorithm that allows for i ) interpreting latent states using highly related input features ; ii ) interpreting predictions using subsets of input features via latent states ; and iii ) interpreting changes in latent states over time. the proposed algorithm is feasible for any model that is differentiable. we demonstrate that this approach enables the identification of a daytime behavioral pattern for predicting nocturnal behavior in a real - world healthcare dataset. | arxiv:2311.17560 |
there has recently been considerable interest in the question whether and under which conditions accelerated cosmological expansion can arise in the asymptotic regions of field space of a $ d $ - dimensional eft. we conjecture that such acceleration is impossible unless there exist metastable de sitter vacua in more than $ d $ dimensions. that is, we conjecture that ` asymptotic acceleration implies de sitter ' ( aa $ \ rightarrow $ ds ). phrased negatively, we argue that the $ d $ - dimensional ` no asymptotic acceleration ' conjecture ( a. k. a. ~ the ` strong asymptotic ds conjecture ' ) follows from the de sitter conjecture in more than $ d $ dimensions. the key idea is that the relevant field - space asymptotics almost always correspond to decompactification and that the only positive energy contribution which decays sufficiently slowly in this regime is the vacuum energy of a higher - dimensional metastable vacuum. this result is in agreement with recent swampland bounds on the potential in the asymptotics in field space from e. g. the species bound, but is significantly more constraining. we further note that for our asymptotic decompactification limits based on higher - dimensional de sitter, the kaluza - klein scale always falls below the hubble scale asymptotically. in fact, this occurs whenever $ | v ' | / v \ leq 2 \ sqrt { ( d + k - 2 ) / k ( d - 2 ) } $ asymptotically, with $ k $ the number of decompactifying internal directions. this is steeper than what is needed for accelerated expansion. | arxiv:2306.17213 |
we study the oscillations of a scalar field on a noncommutative disc implementing the boundary as the limit case of an interaction with an appropriately chosen confining background. the space of quantum fluctuations of the field is finite dimensional and displays the rotational and parity symmetry of the disc. we perform a numerical evaluation of the ( finite ) casimir energy and obtain similar results as for the fuzzy sphere and torus. | arxiv:1307.4464 |
this chapter examines how positivity and order play out in two important questions in mathematical economics, and in so doing, subjects the postulates of continuity, additivity and monotonicity to closer scrutiny. two sets of results are offered : the first departs from eilenberg ' s ( 1941 ) necessary and sufficient conditions on the topology under which an anti - symmetric, complete, transitive and continuous binary relation exists on a topologically connected space ; and the second, from degroot ' s ( 1970 ) result concerning an additivity postulate that ensures a complete binary relation on a { \ sigma } - algebra to be transitive. these results are framed in the registers of order, topology, algebra and measure - theory ; and also beyond mathematics in economics : the exploitation of villegas ' notion of monotonic continuity by arrow - chichilnisky in the context of savage ' s theorem in decision theory, and the extension of diamond ' s impossibility result in social choice theory by basu - mitra. as such, this chapter has a synthetic and expository motivation, and can be read as a plea for inter - disciplinary conversations, connections and collaboration. | arxiv:2007.01952 |
we determine the group of all fourier - mukai type autoequivalences of kuznetsov components of smooth complex cubic threefolds, and provide yet another proof for the fourier - mukai version of categorical torelli theorem for smooth complex cubic threefolds. | arxiv:2304.12669 |
protein phosphorylation is a reversible post - translational modification commonly used by cell signaling networks to transmit information about the extracellular environment into intracellular organelles for the regulation of the activity and sorting of proteins within the cell. for this study we reconstructed a literature - based mammalian kinase - substrate network from several online resources. the interactions within this directed graph network connect kinases to their substrates, through specific phosphosites including kinase - kinase regulatory interactions. however, the " signs " of links, activation or inhibition of the substrate upon phosphorylation, within this network are mostly unknown. here we show how we can infer the " signs " indirectly using data from quantitative phosphoproteomics experiments applied to mammalian cells combined with the literature - based kinase - substrate network. our inference method was able to predict the sign for 321 links and 153 phosphosites on 120 kinases, resulting in signed and directed subnetwork of mammalian kinase - kinase interactions. such an approach can rapidly advance the reconstruction of cell signaling pathways and networks regulating mammalian cells. | arxiv:1005.0017 |
quark and lepton flavor physics presents us with a basic question : can we understand the pattern of masses and mixings of the known quarks and leptons, and how do present and proposed measurements help to advance that goal? topics discussed include the apparent suppression of new flavor - changing effects, the status of quark and lepton mixing, the implications of new measurements of cp asymmetries in heavy quark decays, the impications of forthcoming experiments on the muon ' s anomalous magnetic moment and its transitions to an electron, and what we can hope to learn from electric dipole moments. | arxiv:1309.7980 |
we introduce a new ideal { \ mathfrak d } of the p - adic galois group - ring associated to a real abelian field and a related ideal { \ mathfrak j } for imaginary abelian fields. both result from an equivariant, kummer - type pairing applied to stark units in a z _ p - tower of abelian fields and { \ mathfrak j } is linked by explicit reciprocity to a third ideal { \ mathfrak s } studied more generally in a previous work. this leads to a new and unifying framework for the iwasawa theory of such fields including a real analogue of stickelberger ' s theorem, links with certain fitting ideals and \ lambda - torsion submodules, and a new exact sequence related to the main conjecture. | arxiv:0905.4336 |
continuous variable quantum key distribution ( cv - qkd ), utilizes continuous variables encoding such as the quadra - ture components of the quantized electromagnetic field and coherent detection decoding, offering good compatibility with the existing telecommunications technology and components. continuous variable measurement - device - independent qkd ( cv - mdi - qkd ) can eliminate all the security threats arising from the receiver effectively, the crucial security loophole of cv - qkd implementations. recently, cv - mdi - qkd has attracted extensive attentions and witnessed rapid progress. here, we review the achievements that have been made in the field of cv - mdi - qkd, including the basic principle, advancements in theoretical protocols and experimental demonstrations. finally, we discuss the challenges faced in practical applications and future research directions. | arxiv:2502.16448 |
recently, carraro ( 2005 ) drew attention to the remarkable star cluster whiting 1 by showing that it lies about 40 kpc from the sun and is therefore unquestionably a member of the galactic halo ( b = - 60. 6 deg. ). its cmd indicated that whiting 1 is very young ( 5 gyrs ) for a globular cluster. it is very likely that whiting 1 originated in a dwarf galaxy that has since been disrupted by the milky way. deep ccd photometry in the bvi pass - bands obtained with the vlt is used to improve the quality of the cmd and to determine the cluster ' s luminosity function and surface density profile. high - resolution spectrograms obtained with magellan are used to measure the cluster ' s radial velocity and to place limits on its possible metallicity. the measurements of distance and radial velocity are used to test the cluster ' s membership in the stellar streams from the sgr dsph. from our cmd of whiting 1, we derive new estimates for the cluster ' s age ( 6. 5 gyrs ), metallicity ( [ fe / h ] = - 0. 65 ), and distance ( 29. 4 kpc ). from echelle spectrograms of three stars, we obtain - 130. 6 km / s for the cluster ' s radial velocity and show from measurements of two infra - red caii lines that the [ fe / h ] of the cluster probably lies in the range - 1. 1 to - 0. 4. we demonstrate that the position of whiting 1 on the sky, its distance from the sun, and its radial velocity are identical to within the errors of both the theoretical predictions of the trailing stream of stars from the sgr dsph galaxy and the previous observations of the m giant stars that delineate the streams. with the addition of whiting 1, there is now strong evidence that 6 globular clusters formed within the sgr dsph. | arxiv:astro-ph/0702253 |
causal order can improve the quantum information transmission in teleportation due a noisy entangled resource by using an appropriate measurement state on the control state ruling the causal order. in this work, we get analytically the fidelity for the entire process under an arbitrary measurement over such control state and then we get a perfect teleportation by selecting the optimal measurement on it. we also analyse other values characterizing the imperfect entangled state where a perfect teleportation can not be reached. notably, we determine that the best fidelity does not depend on the probabilities of the control state but on the imperfect initial resource entangled. | arxiv:1911.04550 |
we investigate fickian diffusion in two - dimensional ( 2d ) yukawa liquids using molecular dynamics simulations. we compute the self - van hove correlation function $ g _ s ( r, t ) $, and the self - intermediate scattering function $ f _ s ( k, t ) $ and compare these functions with those obtained from mean - squared displacement msd using the gaussian approximation. according to this approximation, a linear msd with time implies a gaussian behavior for $ g _ s ( r, t ) $ and $ f _ s ( k, t ) $ at all times. surprisingly, we find that these functions deviate from gaussian at intermediate time scales, indicating the failure of the gaussian approximation. furthermore, we quantify these deviations by the non - gaussian parameter, and we find that the deviations increase with decreasing the temperature of the liquid. the origin of the non - gaussian behavior may be the heterogeneous dynamics of dust particles observed in 2d yukawa liquids. | arxiv:2104.05019 |
for any vertex algebra v and any subalgebra a of v, there is a new subalgebra of v known as the commutant of a in v. this construction was introduced by frenkel - zhu, and is a generalization of an earlier construction due to kac - peterson and goddard - kent - olive known as the coset construction. in this paper, we interpret the commutant as a vertex algebra notion of invariant theory. we present an approach to describing commutant algebras in an appropriate category of vertex algebras by reducing the problem to a question in commutative algebra. we give an interesting example of a howe pair ( ie, a pair of mutual commutants ) in the vertex algebra setting. | arxiv:math/0605174 |
the inverse problem of antiplane elasticity on determination of the profiles of $ n $ uniformly stressed inclusions is studied. the inclusions are in ideal contact with the surrounding matrix, the stress field inside the inclusions is uniform, and at infinity the body is subjected to antiplane uniform shear. the exterior of the inclusions, an $ n $ - connected domain, is treated as the image by a conformal map of an $ n $ - connected slit domain with the slits lying in the same line. the inverse problem is solved by quadratures by reducing it to two riemann - hilbert problems on a riemann surface of genus $ n - 1 $. samples of two and three symmetric and non - symmetric uniformly stressed inclusions are reported. | arxiv:1705.06627 |
we study the presence of abelian discrete symmetries in globally consistent orientifold compactifications based on rational conformal field theory. we extend previous work [ 1 ] by allowing the discrete symmetries to be a linear combination of u ( 1 ) gauge factors of the visible as well as the hidden sector. this more general ansatz significantly increases the probability of finding a discrete symmetry in the low energy effective action. applied to globally consistent mssm - like gepner constructions we find multiple models that allow for matter parity or baryon triality. | arxiv:1502.02686 |
experimental data on total and differential elastic cross sections for $ p + p ( \ bar { p } ) $, $ n + p ( \ bar { p } ) $, $ k ^ \ pm + p $, $ k ^ \ pm + n $, $ \ pi ^ \ pm + p $ starting from energy 3. 5 gev in cms are used to determine parameters of vacuum contribution and parameters of basic non vacuum reggeons : $ f $, $ \ omega $, $ \ rho $ and $ a _ 2 $. it is argued that non vacuum contributions to proton - proton and proton - neutron collisions correspond to spectrum in which baryon number is moved from the fragmentation region to central region in rapidity space. in this case it is possible that chemical potential is increased in central region of spectrum of nucleus - nucleus interaction at low energies. this effect might be important for facilities fair and nica. | arxiv:1010.5259 |
a distinct isotopic effect in phi photoproduction at 2 - 5 gev region is identified by examining the production amplitudes due to pomeron - exchange and meson - exchange mechanisms. this effect is mainly caused by the pi - eta interference constrained by su ( 3 ) symmetry and the isotopic structure of the gamma nn coupling in the direct phi - radiation amplitude. it can be tested experimentally by measuring differences in the polarization observables between the gamma - p and gamma - n reactions. | arxiv:nucl-th/9812074 |
asymmetry in the josephson couplings between two superconductors through a quantum dot is studied based on a single impurity anderson model using the numerical renormalization group ( nrg ). specifically, we examine how the difference between the couplings \ gamma _ l and \ gamma _ r affects the ground state, which is known to show a quantum phase transition between a nonmagnetic singlet and a magnetic doublet depending on the various parameters ; the coulomb interaction u, onsite potential \ epsilon _ d, level width \ gamma _ l, \ gamma _ r, caused by the hybridization, and superconducting gaps \ delta _ l and \ delta _ r for the leads on the left and right. our results show that whether the local moment is fully screened or not depends substantially on the asymmetry in the couplings \ gamma _ l \ neq \ gamma _ r. it tends to make the singlet ground state stable, while the size and phase difference of the two superconducting gaps tend to suppress the screening. we also discuss some general symmetry properties of the system and their relation to the current conservation. | arxiv:cond-mat/0606581 |
there are two kinds of solutions of the cauchy problem of first order, the viscosity solution and the more geometric minimax solution and in general they are different. the aim of this article is to show how they are related : iterating the minimax procedure during shorter and shorter time intervals one approaches the viscosity solution. this can be considered as an extension to the contact framework of the result of q. wei in the symplectic case. | arxiv:1611.10293 |
evacuation of robots from a disk has attained a lot of attention recently. we visit the problem from the perspective of fault - tolerance. we consider two robots trying to evacuate from a disk via a single hidden exit on the perimeter of the disk. the robots communicate wirelessly. the robots are susceptible to crash faults after which they stop moving and communicating. we design the algorithms for tolerating one fault. the objective is to minimize the worst - case time required to evacuate both the robots from the disk. when the non - faulty robot chauffeurs the crashed robot, it takes $ \ alpha \ geq 1 $ amount of time to travel unit distance. with this, we also provide a lower bound for the evacuation time. further, we evaluate the worst - case of the algorithms for different values of $ \ alpha $ and the crash time. | arxiv:1906.03024 |
to direct the pupil ' s attention here at once to a great far - reaching law of nature and of thought. it is this, that between two relatively different things or ideas there stands always a third, in a sort of balance, seeming to unite the two. thus, there is here between odd and even numbers one number ( one ) which is neither of the two. similarly, in form, the right angle stands between the acute and obtuse angles ; and in language, the semi - vowels or aspirants between the mutes and vowels. a thoughtful teacher and a pupil taught to think for himself can scarcely help noticing this and other important laws. = = higher mathematics = = = = = higher dimensions and more general classes of numbers = = = integer coordinates of points in euclidean spaces of two or more dimensions also have a parity, usually defined as the parity of the sum of the coordinates. for instance, the face - centered cubic lattice and its higher - dimensional generalizations ( the dn lattices ) consist of all of the integer points whose coordinates have an even sum. this feature also manifests itself in chess, where the parity of a square is indicated by its color : bishops are constrained to moving between squares of the same parity, whereas knights alternate parity between moves. this form of parity was famously used to solve the mutilated chessboard problem : if two opposite corner squares are removed from a chessboard, then the remaining board cannot be covered by dominoes, because each domino covers one square of each parity and there are two more squares of one parity than of the other. the parity of an ordinal number may be defined to be even if the number is a limit ordinal, or a limit ordinal plus a finite even number, and odd otherwise. let r be a commutative ring and let i be an ideal of r whose index is 2. elements of the coset 0 + i { \ displaystyle 0 + i } may be called even, while elements of the coset 1 + i { \ displaystyle 1 + i } may be called odd. as an example, let r = z ( 2 ) be the localization of z at the prime ideal ( 2 ). then an element of r is even or odd if and only if its numerator is so in z. = = = number theory = = = the even numbers form an ideal in the ring of integers, but the odd numbers do not — this is | https://en.wikipedia.org/wiki/Parity_(mathematics) |
the increased use of electronic health records has made possible the automated extraction of medical policies from patient records to aid in the development of clinical decision support systems. we adapted a boosted statistical relational learning ( srl ) framework to learn probabilistic rules from clinical hospital records for the management of physiologic parameters of children with severe cardiac or respiratory failure who were managed with extracorporeal membrane oxygenation. in this preliminary study, the results were promising. in particular, the algorithm returned logic rules for medical actions that are consistent with medical reasoning. | arxiv:2001.04432 |
in the final paper of this series, we extend our results on magnification invariants to the infinite family of a, d, e caustic singularities. we prove that for families of general mappings between planes exhibiting any caustic singularity of the a, d, e family, and for a point in the target space lying anywhere in the region giving rise to the maximum number of lensed images ( real pre - images ), the total signed magnification of the lensed images will always sum to zero. the proof is algebraic in nature and relies on the euler trace formula. | arxiv:0909.5235 |
we present a radial velocity study of the ry tau jet - disk system, designed to determine whether a transfer of angular momentum from disk to jet can be observed. many recent studies report on the rotation of t tauri disks, and on what may be a signature of t tauri jet rotation. however, due to observational difficulties, few studies report on both disk and jet within the same system to establish if the senses of rotation match and hence can be interpreted as a transfer of angular momentum. we report a clear signature of keplerian rotation in the ry tau disk, based on plateau de bure observations. we also report on the transverse radial velocity profile of the ry tau jet close to the star. we identify two distinct profile shapes : a v - shape which appears near jet shock positions, and a flat profile which appears between shocks. we do not detect a rotation signature above 3 sigma uncertainty in any of our transverse cuts of the jet. nevertheless, if the jet is currently in steady - state, the errors themselves provide a valuable upper limit on the jet toroidal velocity of 10 km / s, implying a launch radius of < 0. 45 au. however, possible contamination of jet kinematics, via shocks or precession, prevents any firm constraint on the jet launch point, since most of its angular momentum could be stored in magnetic form rather than in rotation of matter. | arxiv:1502.04481 |
for an arbitrary finite coxeter group w we define the family of cambrian lattices for w as quotients of the weak order on w with respect to certain lattice congruences. we associate to each cambrian lattice a complete fan, which we conjecture is the normal fan of a polytope combinatorially isomorphic to the generalized associahedron for w. in types a and b we obtain, by means of a fiber - polytope construction, combinatorial realizations of the cambrian lattices in terms of triangulations and in terms of permutations. using this combinatorial information, we prove in types a and b that the cambrian fans are combinatorially isomorphic to the normal fans of the generalized associahedra and that one of the cambrian fans is linearly isomorphic to fomin and zelevinsky ' s construction of the normal fan as a " cluster fan. " our construction does not require a crystallographic coxeter group and therefore suggests a definition, at least on the level of cellular spheres, of a generalized associahedron for any finite coxeter group. the tamari lattice is one of the cambrian lattices of type a, and two " tamari " lattices in type b are identified and characterized in terms of signed pattern avoidance. we also show that open intervals in cambrian lattices are either contractible or homotopy equivalent to spheres. | arxiv:math/0402086 |
to ensure a constant load. finally, we analyze nonadaptive allocation algorithms and give tight upper and lower bounds for their performance. | arxiv:0901.4056 |
safe deployment of deep learning systems in critical real world applications requires models to make very few mistakes, and only under predictable circumstances. in this work, we address this problem using an abstaining classifier that is tuned to have $ > $ 95 % accuracy, and then identify the determinants of abstention using lime. essentially, we are training our model to learn the attributes of pathology reports that are likely to lead to incorrect classifications, albeit at the cost of reduced sensitivity. we demonstrate an abstaining classifier in a multitask setting for classifying cancer pathology reports from the nci seer cancer registries on six tasks of interest. for these tasks, we reduce the classification error rate by factors of 2 - - 5 by abstaining on 25 - - 45 % of the reports. for the specific task of classifying cancer site, we are able to identify metastasis, reports involving lymph nodes, and discussion of multiple cancer sites as responsible for many of the classification mistakes, and observe that the extent and types of mistakes vary systematically with cancer site ( e. g., breast, lung, and prostate ). when combining across three of the tasks, our model classifies 50 % of the reports with an accuracy greater than 95 % for three of the six tasks \ edit, and greater than 85 % for all six tasks on the retained samples. furthermore, we show that lime provides a better determinant of classification than measures of word occurrence alone. by combining a deep abstaining classifier with feature identification using lime, we are able to identify concepts responsible for both correctness and abstention when classifying cancer sites from pathology reports. the improvement of lime over keyword searches is statistically significant, presumably because words are assessed in context and have been identified as a local determinant of classification. | arxiv:2009.05094 |
a new finite element formulation for the kirchhoff plate model is presented. the method is a displacement formulation with the deflection and the rotation vector as unknowns and it is based on ideas stemming from a stabilized method for the reissner - - mindlin model and a method to treat a free boundary. optimal a - priori and a - posteriori error estimates are derived. | arxiv:math/0611690 |
in this paper we compare the experimental hera data with the next - to - leading order approach ( nlo ) of ref. [ c. ~ contreras, e. ~ levin, r. ~ meneses and m. ~ sanhueza, eur. phys. j. c 80 ( 2020 ) no. 11, 1029 ). this approach includes the re - summed nlo corrections to the kernel of the evolution equation, the correct asymptotic behaviour in the nlo at $ \ tau = r ^ 2 q ^ 2 _ s \, \ gg \, 1 $ ; the impact parameter dependence of the saturation scale in accord with the froissarrt theorem as well as the non - linear corrections. in this paper, we successfully describe the experimental data with the quality, which is not worse, than in the leading order fits with larger number of the phenomenological parameters. it is demonstrated, that the data could be described, taking into account both the diffusion on $ \ ln ( k _ t ) $, which stems from perturbative qcd, and the gribov ' s diffusion in impact parameters. it is shown an ability to describe the data at rather large values of $ \ alpha _ s $. | arxiv:2106.06214 |
we present a next - to - leading order qcd calculation of inclusive dijet photoproduction in ultraperipheral pb - pb collisions at the lhc and show that the results agree very well with various kinematic distributions measured by the atlas collaboration. the effect of including these data in ncteq or epps16 nuclear parton density functions ( npdfs ) is then studied using the bayesian reweighting technique. for an assumed total error of 5 \ % on the final data, its inclusion would lead to a significant reduction of the npdf uncertainties of up to a factor of two at small values of the parton momentum fraction. as an outlook, we discuss future analyes of diffractive npdfs, which are so far completely unknown. | arxiv:1909.08954 |
the differentiation of noisy signals using the family of homogeneous differentiators is considered. it includes the high - gain ( linear ) as well as robust exact ( discontinuous ) differentiator. to characterize the effect of noise and disturbance on the differentiation estimation error, the generalized, homogeneous $ \ mathcal { l } _ 2 $ - gain is utilized. analog to the classical $ \ mathcal { l } _ p $ - gain, it is not defined for the discontinuous case w. r. t. disturbances acting on the last channel. thus, only continuous differentiators are addressed. the gain is estimated using a differential dissipation inequality, where a scaled lyapunov function acts as storage function for the homogeneous $ \ mathcal { l } _ 2 $ supply rate. the fixed differentiator gains are scaled with a gain - scaling parameter similar to the high - gain differentiator. this paper shows the existence of an optimal scaling which ( locally ) minimizes the homogeneous $ \ mathcal { l } _ 2 $ - gain estimate and provides a procedure to obtain it. differentiators of dimension two are considered and the results are illustrated via numerical evaluation and a simulation example. | arxiv:2311.10519 |
speech - based assessment of the schizophrenia spectrum has been widely researched over in the recent past. in this study, we develop a deep learning framework to estimate schizophrenia severity scores from speech using a feature fusion approach that fuses articulatory features with different self - supervised speech features extracted from pre - trained audio models. we also propose an auto - encoder - based self - supervised representation learning framework to extract compact articulatory embeddings from speech. our top - performing speech - based fusion model with multi - head attention ( mha ) reduces mean absolute error ( mae ) by 9. 18 % and root mean squared error ( rmse ) by 9. 36 % for schizophrenia severity estimation when compared with the previous models that combined speech and video inputs. | arxiv:2411.06033 |
in this paper, we build from previous work ( bustard et al. 2018 ) and present simulations of recent ( within the past gyr ), magnetized, cosmic ray driven outflows from the large magellanic cloud ( lmc ), including our first attempts to explicitly use the derived star formation history of the lmc to seed outflow generation. we run a parameter set of simulations for different lmc gas masses and cosmic ray transport treatments, and we make preliminary comparisons to published outflow flux estimates, neutral and ionized hydrogen observations, and faraday rotation measure maps. we additionally report on the gas mass that becomes unbound from the lmc disk and swept by ram pressure into the trailing magellanic stream. we find that, even for our largest outburst, the mass contribution to the stream is still quite small, as much of the outflow - turned - halo gas is shielded on the lmc ' s far - side due to the lmc ' s primarily face - on infall through the milky way halo over the past gyr. on the lmc ' s near - side, past outflows have fought an uphill battle against ram pressure, with near - side halo mass being at least a factor of a few smaller than the far - side. absorption line studies probing only the lmc foreground, then, may be severely underestimating the total mass of the lmc halo formed by outflows. | arxiv:1911.02021 |
the transition of our energy system to renewable energies is necessary in order not to heat up the climate any further and to achieve climate neutrality. the use of wind energy plays an important role in this transition in germany. but how much wind energy can be used and what are the possible consequences for the atmosphere if more and more wind energy is used? | arxiv:2304.14159 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.