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Generation of particular polarization states of light, encoding information
in polarization degree of freedom, and efficient measurement of unknown
polarization are the key tasks in optical metrology, optical communications,
polarization-sensitive imaging, and photonic information processing. Liquid
crystal devices have proved to be indispensable for these tasks, though their
limited precision and the requirement of a custom design impose a limit of
practical applicability. Here we report fast preparation and detection of
polarization states with unprecedented accuracy using liquid-crystal cells
extracted from common twisted nematic liquid-crystal displays. To verify the
performance of the device we use it to prepare dozens of polarization states
with average fidelity 0.999(1) and average angle deviation 0.5(3) deg. Using
four-projection minimum tomography as well as six-projection Pauli measurement,
we measure polarization states employing the reported device with the average
fidelity of 0.999(1). Polarization measurement data are processed by the
maximum likelihood method to reach a valid estimate of the polarization state.
In addition to the application in classical polarimetry, we also employ the
reported liquid-crystal device for full tomographic characterization of a
three-mode Greenberger--Horne--Zeilinger entangled state produced by a photonic
quantum processor.
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Great case. The tempered glass screen does not cling ...
Great case. The tempered glass screen does not cling at all, and it’s too small. I either got the wrong one or I was missing a portion of it. I looked through the instructions very closely and follow them very closely but what I got was the film that was way too small
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As part of an ongoing series of deep GMRT surveys we have observed the
Spitzer extragalactic First Look Survey field, producing the deepest wide-field
610-MHz survey published to date. We reach an rms noise of 30 microJy/beam
before primary beam correction, with a resolution of ~6 arcsec over an area of
~4 square degrees. By combining these observations with the existing 1.4-GHz
VLA survey produced by Condon et al. (2003), along with infrared data in up to
seven wavebands from the Spitzer Space Telescope, optical photometry from SDSS
and a range of spectroscopic redshift surveys, we are able to study the
relationship between radio luminosity and star formation rate in star-forming
galaxies up to z ~ 1. The large amount of multi-wavelength data available
allows accurate k-corrections to be performed in the radio due to the knowledge
of the radio spectral index, and in the infrared through the use of a
semi-empirical radiative transfer model which models star-forming regions, warm
dust surrounding these regions, and diffuse interstellar dust, taking into
account the star formation rate, star formation history and hydrogen column
density within each galaxy. A strong correlation is seen between radio
luminosity and infrared-derived star formation rates, which is best fit by a
slightly non-linear power-law. We look for cosmic evolution in the comparative
radio brightness of star-forming galaxies by searching for deviations away from
the global relationship. Any such deviation would indicate a systematic
variation in one or more of the properties controlling synchrotron radiation,
in particular an increase in the magnetic field strengths of star-forming
galaxies. The data shows no evidence for such an effect, suggesting that there
has been little evolution in the magnetic fields of galaxies since z ~ 1.
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We study the limit of high activation energy of a special Fokker-Planck
equation, known as Kramers-Smoluchowski (K-S) equation. This equation governs
the time evolution of the probability density of a particle performing a
Brownian motion under the influence of a chemical potential H/e. We choose H
having two wells corresponding to two chemical states A and B. We prove that
after a suitable rescaling the solution to (K-S) converges, in the limit of
high activation energy (e -> 0), to the solution of a simple system modeling
the diffusion of A and B, and the reaction A <-> B.
The aim of this paper is to give a rigorous proof of Kramer's formal
derivation and to embed chemical reactions and diffusion processes in a common
variational framework which allows to derive the former as a singular limit of
the latter, thus establishing a connection between two worlds often regarded as
separate.
The singular limit is analysed by means of Gamma-convergence in the space of
finite Borel measures endowed with the weak-* topology.
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Image inpainting techniques have shown significant improvements by using deep
neural networks recently. However, most of them may either fail to reconstruct
reasonable structures or restore fine-grained textures. In order to solve this
problem, in this paper, we propose a two-stage model which splits the
inpainting task into two parts: structure reconstruction and texture
generation. In the first stage, edge-preserved smooth images are employed to
train a structure reconstructor which completes the missing structures of the
inputs. In the second stage, based on the reconstructed structures, a texture
generator using appearance flow is designed to yield image details. Experiments
on multiple publicly available datasets show the superior performance of the
proposed network.
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Coronal loops are fundamental building blocks of the solar active regions and
the corona. Therefore, a clear understanding of the physics of coronal loops
will help us understand the physics of active region heating in particular and
coronal heating in general. This requires a precise measurement of physical
quantities such as electron densities and filling factors, temperatures, and
flows in coronal loops. In this paper we have carried out an investigation of a
spatially well resolved coronal loop using the EIS onboard Hinode to measure
the above mentioned physical quantities. Based on this study we find that a
nano-flare model could explain most of the observed characteristics of this
loop.
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I got a box of crumbs!!
I love these cookies but when I received the 12 packages they had been packed with the unprotected up side facing down so any time the box hit the ground it broke the cookies and I got a box of badly broken crumbs!!! There was no padding at all in the box 📦!
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"Faint" is a song by the American rock band Linkin Park, from their second studio album "Meteora", the song would later be featured on the group's mashup EP, where it was mashed up with lyrics of the song Jigga What from "Vol. 2... Hard Knock Life", is the third studio album, by which American rapper?
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Crap stuck on sticky area
Unfortunately, my diamond painting arrived with all kinds of crap stuck to the sticky part, under the plastic sheet. This "crap" included dirt, rocks, twine, hair and dust clumps. It was a gift, and I didn't have time to exchange, so I spent hours with needle thin tweezers picking everything off. Finished product was beautiful, though.
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The only restriction on the values of the elasticity parameters is the
stability condition. Within this condition, we examine Christoffel equation for
nondetached $qP$ slowness surfaces in transversely isotropic media. If the $qP$
slowness surface is detached, each root of the solubility condition corresponds
to a distinct smooth wavefront. If the $qP$ slowness surface is nondetached,
the roots are elliptical but do not correspond to distinct wavefronts; also,
the $qP$ and $qSV$ slowness surfaces are not smooth.
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In this paper, we develop a non-singular continuum theory of point defects
based on a second strain gradient elasticity theory, the so-called gradient
elasticity of bi-Helmholtz type. Such a generalized continuum theory possesses
a weak nonlocal character with two internal material lengths and provides a
mechanics of defects without singularities. Gradient elasticity of bi-Helmholtz
type gives a natural and physical regularization of the classical singularities
of defects, based on higher order partial differential equations. Point defects
embedded in an isotropic solid are considered as eigenstrain problem in
gradient elasticity of bi-Helmholtz type. Singularity-free fields of point
defects are presented. The displacement field as well as the first, the second
and the third gradients of the displacement are derived and it is shown that
the classical singularities are regularized in this framework. This model
delivers non-singular expressions for the displacement field, the first
displacement gradient and the second displacement gradient. Moreover, the
plastic distortion (eigendistortion) and the gradient of the plastic distortion
of a dilatation centre are also non-singular and are given in terms of a form
factor (shape function) of a point defect. Singularity-free expressions for the
interaction energy and the interaction force between two dilatation centres and
for the interaction energy and the interaction force of a dilatation centre in
the stress field of an edge dislocation are given. The results are applied to
calculate the finite self-energy of a dilatation centre.
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So we need to add doctors to the businesses we monitor for respecting our civil right to protect ourselves and our families with firearms, so we can avoid spending our hard-earned money to enrich hoplophobes. If people won't mind their own business we have to cut them out of our lives. Get the app for your phone so you can know if businesses you support support your civil right to keep and bear arms.
http://2afriendly.com
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I love Brian Yuzna's other work, even cruder stuff like 'Necronomicon', but 'Progeny' was too much even for me. My chief complaint is that it's needlessly exploitative of Jillian McWhirter's nudity, I'm no prude but these nude scenes just drag on and on and on... only to culminate (virtually every time) in a tawdry *wink, nudge* insinuation of sexual violence. The scene where she attempts a coat hanger abortion after several minutes of naked screaming is a prime example. Arnold Vosloo's 'performance' is utterly turgid, but even Jeffrey Coombs couldn't save this festering heap of a film. The aliens are boring, the uniformly dull lighting saps your interest, and the plot is absolutely predictable. The only highlights for me were an all-too-brief glimpse of the aliens' true form (very nice model) and the scene where Vosloo finds his wife in the closet was OK too. But you've been warned.
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In this paper we study the use of Machine Learning techniques to exploit
kinematic information in VH, the production of a Higgs in association with a
massive vector boson. We parametrise the effect of new physics in terms of the
SMEFT framework. We find that the use of a shallow neural network allows us to
dramatically increase the sensitivity to deviations in VH respect to previous
estimates. We also discuss the relation between the usual measures of
performance in Machine Learning, such as AUC or accuracy, with the more adept
measure of Asimov significance. This relation is particularly relevant when
parametrising systematic uncertainties. Our results show the potential of
incorporating Machine Learning techniques to the SMEFT studies using the
current datasets.
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Systematic measurements on the rate capability of thin MWPCs operated in
Xenon, Argon and Neon mixtures using CO2 as UV-quencher are presented. A good
agreement between data and existing models has been found, allowing us to
present the rate capability of MWPCs in a comprehensive way and ultimately
connect it with the mobilities of the drifting ions.
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We study analytically and numerically the influence of the quasiparticle
charge imbalance on the dynamics of the asymmetric Josephson stack formed by
two inequivalent junctions: the fast capacitive junction $JJ_{1}$ and slow
non-capacitive junction $JJ_{2}$. We find, that the switching of the fast
junction into resistive state leads to significant increase of the effective
critical current of the slow junction. At the same time, the initial switching
of the slow junction may either increase or decrease the effective critical
current of the fast junction, depending on ratio of their resistances and the
value of the capacitance. Finally, we have found that the slow quasiparticle
relaxation (in comparison with Josephson times) leads to appearance of the
additional hysteresis on current-voltage characteristics.
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The layered ternary sp conductor NaAlSi, possessing the iron-pnictide "111"
crystal structure, superconducts at 7 K. Using density functional methods, we
show that this compound is an intrinsic (self-doped) low-carrier-density
semimetal with a number of unusual features. Covalent Al-Si valence bands
provide the holes, and free-electron-like Al 3s bands, which propagate in the
channel between the neighboring Si layers, dip just below the Fermi level to
create the electron carriers. The Fermi level (and therefore the
superconducting carriers) lies in a narrow and sharp peak within a pseudogap in
the density of states. The small peak arises from valence bands which are
nearly of pure Si, quasi-two-dimensional, flat, and coupled to Al conduction
bands. Isostructural NaAlGe, which is not superconducting above 1.6 K, has
almost exactly the same band structure except for one missing piece of small
Fermi surface. Certain deformation potentials induced by Si and Na
displacements along the c-axis are calculated and discussed. It seems likely
that the mechanism of pairing is related to that of several other lightly doped
two-dimensional nonmagnetic semiconductors (TiNCl, ZrNCl, HfNCl), which is not
well understood but apparently not of phonon origin.
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We present EDA: easy data augmentation techniques for boosting performance on
text classification tasks. EDA consists of four simple but powerful operations:
synonym replacement, random insertion, random swap, and random deletion. On
five text classification tasks, we show that EDA improves performance for both
convolutional and recurrent neural networks. EDA demonstrates particularly
strong results for smaller datasets; on average, across five datasets, training
with EDA while using only 50% of the available training set achieved the same
accuracy as normal training with all available data. We also performed
extensive ablation studies and suggest parameters for practical use.
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In recent years, there has been a proliferation of online gambling sites,
which made gambling more accessible with a consequent rise in related problems,
such as addiction. Hence, the analysis of the gambling behaviour at both the
individual and the aggregate levels has become the object of several
investigations. In this paper, resorting to classical methods of the kinetic
theory, we describe the behaviour of a multi-agent system of gamblers
participating in lottery-type games on a virtual-item gambling market. The
comparison with previous, often empirical, results highlights the ability of
the kinetic approach to explain how the simple microscopic rules of a
gambling-type game produce complex collective trends, which might be difficult
to interpret precisely by looking only at the available data.
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In this paper we propose an approach to homotopical algebra where the basic
ingredient is a category with two classes of distinguished morphisms: strong
and weak equivalences. These data determine the cofibrant objects by an
extension property analogous to the classical lifting property of projective
modules. We define a Cartan-Eilenberg category as a category with strong and
weak equivalences such that there is an equivalence between its localization
with respect to weak equivalences and the localised category of cofibrant
objets with respect to strong equivalences. This equivalence allows us to
extend the classical theory of derived additive functors to this non additive
setting. The main examples include Quillen model categories and functor
categories with a triple, in the last case we find examples in which the class
of strong equivalences is not determined by a homotopy relation. Among other
applications, we prove the existence of filtered minimal models for \emph{cdg}
algebras over a zero-characteristic field and we formulate an acyclic models
theorem for non additive functors.
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We here develop an improved way of using a rotating star as a clock, set it
using the Sun, and demonstrate that it keeps time well. This technique, called
gyrochronology, permits the derivation of ages for solar- and late-type main
sequence stars using only their rotation periods and colors. The technique is
clarified and developed here, and used to derive ages for illustrative groups
of nearby, late-type field stars with measured rotation periods. We first
demonstrate the reality of the interface sequence, the unifying feature of the
rotational observations of cluster and field stars that makes the technique
possible, and extends it beyond the proposal of Skumanich by specifying the
mass dependence of rotation for these stars. We delineate which stars it cannot
currently be used on. We then calibrate the age dependence using the Sun. The
errors are propagated to understand their dependence on color and period.
Representative age errors associated with the technique are estimated at ~15%
(plus possible systematic errors) for late-F, G, K, & early-M stars. Ages
derived via gyrochronology for the Mt. Wilson stars are shown to be in good
agreement with chromospheric ages for all but the bluest stars, and probably
superior. Gyro ages are then calculated for each of the active main sequence
field stars studied by Strassmeier and collaborators where other ages are not
available. These are shown to be mostly younger than 1Gyr, with a median age of
365Myr. The sample of single, late-type main sequence field stars assembled by
Pizzolato and collaborators is then assessed, and shown to have gyro ages
ranging from under 100Myr to several Gyr, and a median age of 1.2Gyr. Finally,
we demonstrate that the individual components of the three wide binaries
XiBooAB, 61CygAB, & AlphaCenAB yield substantially the same gyro ages.
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We examine the dependence of parton distribution functions (PDFs) on the
value of the QCD coupling strength $\alpha_{s}(M_{Z})$. We explain a simple
method that is rigorously valid in the quadratic approximation normally applied
in PDF fitting, and fully reproduces the correlated dependence of theoretical
cross sections on $\alpha_s$ and PDF parameters. This method is based on a
statistical relation that allows one to add the uncertainty produced by
$\alpha_s$, computed with some special PDF sets, in quadrature with the PDF
uncertainty obtained for the fixed $\alpha_s$ value (such as the CTEQ6.6 PDF
set). A series of four CTEQ6.6AS PDFs realizing this approach, for $\alpha_s$
values in the interval $0.116 \leq \alpha_{s}(M_{Z}) \leq 0.120$, is presented.
Using these PDFs, the combined $\alpha_{s}$ and PDF uncertainty is assessed for
theoretical predictions at the Fermilab Tevatron and Large Hadron Collider.
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Finally a comment that considers the plight of this young man that brought him to this place. There are too many like him that start life out in the negative digits. Some people that start life way below others do make it in life & don't become murderers, but I don't think this is the norm. I read about two boys that were black (which was already a strike against them) that were in prison. Both their IQs were really low. Doesn't mean that their IQ was that low to begin with. There is something disturbing when you hear that one young man was passed around for sex to his buddies by his step-father. The other boy's mom sat him on a hot burner on the stove to punish him for being a bad boy. I guess this taught him to not behave! Yeah, right. It doesn't mean that they should go free, but I guess I can feel some compassion for people like this due to their circumstances. Also, statements like "I was treated badly and I turned out okay." You weren't born with his basic traits.
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Worker: Cemu is a Wii U video game console emulator for Microsoft Windows-based personal computers, typically, the emulator updates once every two to four weeks, with supporters of which membership platform that provides business tools for creators to run a subscription content service, as well as ways for artists to build relationships and provide exclusive experiences to their subscribers, or "patrons", were receiving updates a week earlier than the public release?
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Solutions for the fields in a coated cylinder where the core radius is bigger
than the shell radius are seemingly unphysical, but can be given a physical
meaning if one transforms to an equivalent problem by unfolding the geometry.
In particular the unfolded material can act as an impedance matched hyperlens,
and as the loss in the lens goes to zero finite collections of polarizable line
dipoles lying within a critical region surrounding the hyperlens are shown to
be cloaked having vanishingly small dipole moments. This cloaking, which occurs
both in the folded geometry and the equivalent unfolded one, is due to
anomalous resonance, where the collection of dipoles generates an anomalously
resonant field, which acts back on the dipoles to essentially cancel the
external fields acting on them.
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Seams split on side of pouch.
Yes, I would [and did] purchase this again despite I found the interior side [back of pouch] seams had split close to the bottom rear. I "repaired' it by melting the loose and exposed nylon edges with my propane torch, and then re-sealed the seams with a waterproof 'cement'. OK, good to go. Don't look too sharp, but it's functional and stayed together. I suspect it came apart because there was not sufficient sewn material overlap AND the manufacturer did not seal the nylon edges prior to sewing.
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Built on a realistic multiband tight-binding model, mirror symmetry is used
to map a calcium-intercalated bilayer graphene Hamiltonian into two independent
single layer graphene-like Hamiltonians with renormalized hopping. The
quasiparticles exhibit two types of chirality. Here a quasi-particle consists
of two electrons from opposing layers where possess an additional quantum
number called "cone index" which can be regarded as the eigenvalue of mirror
symmetry operations. To obtain tight-binding parameters, both effective
monolayer Schrodinger equations are solved analytically and fitted to
first-principles band structure results. Two quasi-particles (four electrons)
can team up to build a Cooper pair with even or odd chirality. Treatment of the
pairing Hamiltonian leads to two decoupled gap equations. The pairing of
quasi-particles with different cone indexes is forbidden. The decoupled gap
equations are solved analytically to obtain all the possible superconducting
phases. Two nearly "flat bands" crossing the Fermi energy, each related to the
graphene-like structures, are responsible for two distinct superconductivity
gaps that emerge.
Depending on how much these bands are affected by the intercalant and which
is closer to the Fermi energy, distorted s-wave or d-wave superconductivity may
become dominant. Numerical calculations reveal that d-wave superconductivity is
dominant in both sectors. For these two dominant phases, within the range of
0-6 K which superconductivity has been observed, numerically the transition
from single-gap to dual-gap superconductivity is possible. Adopting the two-gap
viewpoint of superconductivity in C$_6$CaC$_6$, the dominant $d$-wave states
should have the same critical temperature. Around $T_c=2K$ these two relations
intersect, otherwise, superconductivity has been realized just in one of these
two sectors and disappears in the other one.
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Using a definition of the bulk frame within 2d Jackiw-Teitelboim gravity, we
go into the bulk from the Schwarzian boundary. Including the path integral over
the Schwarzian degrees of freedom, we discuss the quantum gravitational Unruh
effect and the Planckian black-body spectrum of the thermal atmosphere. We
analyze matter entanglement entropy and how the entangling surface should be
defined in quantum gravity. Finally, we reanalyze a semi-classical model for
black hole evaporation studied in JHEP 1607, 139 (2016) and compute the
entanglement between early and late Hawking radiation, illustrating information
loss in the semi-classical framework.
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Cardiff, Wales. A bunch of 5 mates are deeply bored in this town. There's Jip who works in a clothes shop. Coop, an easy-going DJ. Nina, inseparable from her best friend Lulu and Moff. The week is hell for them and they only wait for one thing: the week-end. At this time, they got out to a nightclub and to the sound of tech no music, they experience different drugs, particularly ecstasy. Then, they usually continue the party to a friend's. At the end of this really good time on Sunday, the feelings are the following ones: tiredness, melancholy, just the memory of a crazy night...<br /><br />Surfing on the wave of the notorious success of "Trainspotting" (1996), this debut movie written and directed by Justin Kerrigan brings and develops a new variation about the notion of hedonism. It means: how to have fun as much as possible while knowing that you have a shortened lapse of time. Indeed, as I have previously written, for the 5 main characters of the movie, the week is hell and the weekend is the only time they can free themselves and have a wild time without the single pressure (besides, Jip in one sequence talks about the positive aspects of shooting oneself: you are numb, you don't feel any pressure, you are like an astronaut in orbit above the earth. Kerrigan's relentless directorial style expresses very well the spirit of debauchery and care freeness of the 5 protagonists. They only live to take advantage as much as possible of an hedonist week-end. Furthermore, to spice up a little more the festive atmosphere in which his movie bathes, Kerrigan isn't afraid to include dreamlike sequences which represent his characters' fantasy or embarrassments. Then, "Human Traffic" (1999) is also served by a particularly bouncy sound track. The amount? A perfect symbiosis between the sound and the music. At last, this week-end of euphoria enables to shelve momentarily the usual drab image of the popular social classes, British cinema has studied a lot.<br /><br />Notwithstanding, when a movie (conscientiously or not) exploits the fame of another famous one, it rarely matches the brilliance of its predecessor. "Human Traffic" is in this condition. There's little inventiveness at the level of the narrative structure and the introduction of the characters and one can note down a few useless digressions (Jip who, in the nightclub goes in the manager's office and tells him a cock-and-bull story so as to enable Moff to enter the club but that's no use because the latter succeeds in coming without problems). One can also blame Kerrigan to overlook the dramatic sides that the story could have involved. His movie can also be read as a transition from euphoria to paranoia and the dramatic connotations of this second pole aren't virtually explored. It's a shame! It could have conveyed the following message: even in the happiest moments, there can be something terrible preparing which can flop them. The same remark could also be said when Coop has a fit of jealousy because Nina broaches a guy.<br /><br />It may not be the last great film of the nineties as it is billed on the DVD cover but "Human Traffic" is to be taken as a good and incisive little movie which conveys with the styles and the fashions of the end of the twentieth century, a will to have fun without ulterior motives and trouble. An ideal movie to start any party or before going to a club.
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We propose a quantum heuristic algorithm to solve a traveling salesman
problem by generalizing Grover search. Sufficient conditions are derived to
greatly enhance the probability of finding the tours with extremal costs,
reaching almost to unity and they are shown characterized by statistical
properties of tour costs. In particular for a Gaussian distribution of the
tours along the cost we show that the quantum algorithm exhibits the quadratic
speedup of its classical counterpart, similarly to Grover search.
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Cell experiments with large, short electric field pulses of opposite polarity
reveal a remarkable phenomenon: Bipolar cancellation (BPC). Typical defining
experiments involve quantitative observation of tracer molecule influx at times
of order 100 s post pulsing. Gowrishankar et al. BBRC 2018 503:1194-1199 shows
that long-lived pores and altered partitioning or hindrance due to inserted
occluding molecules can account for BPC. In stark contrast, the Assisted
Discharge (AD) hypothesis, Pakhomov et al. CellMol- LifeSci 2014
71(22):4431-4441; Fig. 6, only involves early times of a microsecond down to
nanoseconds. Further, well established terminology for cell membrane discharge
relates to membrane potential decays shortly after pulsing. Discharge is silent
on molecular or ionic transport, and does not address the fact that tracer
molecule uptake vs time is measure at about 100s after pulsing ceases. Our
critique of AD notes that there can be an association of AD with BPC, but
associations are only necessary, not sufficient. A BPC mechanism hypothesis
must be shown to be causal, able to describe time-dependent molecular influx.
The two hypotheses involve very different time-scales (less than a microsecond
vs 100 s) and very different quantities (volts/s vs molecules/s). Unlike
pore-based hypotheses the AD hypothesis lacks explicit molecular transport
mechanisms, and does not address the greatly delayed measured molecular uptake.
We conclude that AD is an implausible candidate for explaining BPC.
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We carry out Direct Numerical Simulation (DNS) of flows in closed rectangular
ducts with several aspect ratios. The Navier-Stokes equations are discretized
through a second-order finite difference scheme, with non-uniform grids in two
directions. The duct cross-sectional area is maintained constant as well as the
flow rate, which allows to investigate which is the appropriate length scale in
the Reynolds number for a good scaling in the laminar and in the fully
turbulent regimes. We find that the Reynolds number based on the half length of
the short side leads to a critical Reynolds number which is independent on the
aspect ratio (AR), for ducts with AR>1. The mean and rms wall-normal velocity
profiles are found to scale with the local value of the friction velocity. At
high friction Reynolds numbers, the Reynolds number dependence is similar to
that in turbulent plane channels, hence flows in rectangular ducts allow to
investigate the Reynolds number dependency through a reduced number of
simulations. At low Re the profiles of the statistics differ from those in the
two-dimensional channel due to the interaction of flow structures of different
size. The projection of the velocity vector and of the Reynolds stress tensor
along the eigenvectors of the strain-rate tensor yields reduced Reynolds stress
anisotropy, and simple turbulent kinetic energy budgets.
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Based on analysis of photometric observations of nearby M type stars obtained
with ASAS, 31 periodic variables were detected. The determined periods are
assumed to be related to rotation periods of the investigated stars. Among them
10 new variables with periods longer than 10 days were found, which brings the
total number of slowly rotating M stars with known rotation periods to 12
objects.
X-ray activity and rotation evolution of M stars follows the trends observed
in G-K type stars. Rapidly rotating stars are very active and activity
decreases with increasing rotation period but the period-activity relation is
mass-dependent which suggests that the rotation period alone is not a proper
measure of activity. The investigated stars were grouped according to their
mass and the empirical turnover time was determined for each group. It
increases with decreasing mass more steeply than for K type stars for which a
flat dependence had been found. The resulting Rossby number-activity relation
shows an exponential decrease of activity with increasing Rossby number.
The analysis of space motions of 27 single stars showed that all rapidly
rotating and a few slowly rotating stars belong to young disk (YD) whereas all
old disk (OD) stars are slowly rotating. The median rotation period of YD stars
is about 2 days and that of OD stars is equal to 47 days, i.e. nearly 25 times
longer. The average X-ray flux of OD stars is about 1.7 dex lower than YD stars
in a good agreement with the derived Rossby number-activity formula
supplemented with rotation-age relation and in a fair agreement with recent
observations but in a disagreement with the Skumanich formula supplemented with
the activity-rotation relation.
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We study the problem of separating a mixture of distributions, all of which
come from interventions on a known causal bayesian network. Given oracle access
to marginals of all distributions resulting from interventions on the network,
and estimates of marginals from the mixture distribution, we want to recover
the mixing proportions of different mixture components.
We show that in the worst case, mixing proportions cannot be identified using
marginals only. If exact marginals of the mixture distribution were known,
under a simple assumption of excluding a few distributions from the mixture, we
show that the mixing proportions become identifiable. Our identifiability proof
is constructive and gives an efficient algorithm recovering the mixing
proportions exactly. When exact marginals are not available, we design an
optimization framework to estimate the mixing proportions.
Our problem is motivated from a real-world scenario of an e-commerce
business, where multiple interventions occur at a given time, leading to
deviations in expected metrics. We conduct experiments on the well known
publicly available ALARM network and on a proprietary dataset from a large
e-commerce company validating the performance of our method.
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Chris Nolan's labyrinth like noir about voyeurism and identity is amazing from start to finish. A first film is as complex as "Memento" or "The Prestige", though maybe a little harder to get a handle on. Still it smacks of originality and creative drive, and has a "twist" as intellectually challenging as it is realistic pulp. Few film makers have made as good of use of their editors and attention to narrative that Nolan has. The story is about a bored writer who likes to follow random strangers down the street, until he follows someone, whose noticed him following others, and has been following him in tern, from there the complexity escalates and identities begin to rearrange. More naturalistic and realist than Nolan's later work but just as razor sharp.
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A large amount of research about multimodal inference across text and vision
has been recently developed to obtain visually grounded word and sentence
representations. In this paper, we use logic-based representations as unified
meaning representations for texts and images and present an unsupervised
multimodal logical inference system that can effectively prove entailment
relations between them. We show that by combining semantic parsing and theorem
proving, the system can handle semantically complex sentences for
visual-textual inference.
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With all due respect, you are missing my point. Both sides have chemical weapons, but only ISIS and the Assad regime have been documented as using them. As I specified in my comment, ISIS isn't there. This means this can't be blamed on ISIS. Since al-Nusra Front has no jet fighters, it leaves either the Russians or the Syrians. Organizations like Amnesty International have confirmed that it was an air strike.
Just because you've never heard of air to surface missiles being used in chemical attacks doesn't mean it doesn't exist. Cold War Soviet Navy doctrine, for example, assumed a chemical warfare environment and all Russian tactical weapons, including air to surface missiles, can be configured to carry chemical weapons. The warhead is like any other once fitted to the airplane.
As chemical weapons expert, Col. Hamish de Bretton-Gordon, told BBC Radio 4 "If you blow up sarin, you destroy it.". This would preclude an airstrike on a chemical weapons facility.
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Very disappointed
The bottles I received had been used. There was a water line at the bottom of each bottle. Plus the starfish ornaments where not attached to the bottles as shown. There was glue on the ropes on the bottles where you could tell that they once had been. Very disappointed! These were for my mom and I had them shipped directly to her. She was supposed to receive a nice gift but all she got was used merchandise.
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The city had it right. There isn't enough use the pool can't exist without subsidies. Go the SARC route and sell yourself to the YMCA, OMC and Jamestown. Would like to know the percent of population using the pool on a regular basis before voting - but am leaning to "No".
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High time resolution spectroscopy of roAp stars at large telescopes has led
to a major breakthrough in our understanding of magnetoacoustic pulsations in
these interesting objects. New observations have allowed to uncover a number of
intricate relations between stellar oscillations, magnetic field, and chemical
inhomogeneities. It is now understood that unusual pulsational characteristics
of roAp stars arise from an interplay between short vertical length of
pulsation waves and extreme chemical stratification. Here I review results of
recent studies which utilize these unique properties to map 3D pulsation
geometry using a combination of Doppler imaging, vertical pulsation tomography,
interpretation of line profile variation, and ultraprecise space photometry. I
also describe recent attempts to interpret theoretically the complex
observational picture of roAp pulsations.
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Thomson problem is a classical problem in physics to study how $n$ number of
charged particles distribute themselves on the surface of a sphere of $k$
dimensions. When $k=2$, i.e. a 2-sphere (a circle), the particles appear at
equally spaced points. Such a configuration can be computed analytically.
However, for higher dimensions such as $k \ge 3$, i.e. the case of 3-sphere
(standard sphere), there is not much that is understood analytically. Finding
global minimum of the problem under these settings is particularly tough since
the optimization problem becomes increasingly computationally intensive with
larger values of $k$ and $n$. In this work, we explore a wide variety of
numerical optimization methods to solve the Thomson problem. In our empirical
study, we find stochastic gradient based methods (SGD) to be a compelling
choice for this problem as it scales well with the number of points.
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We present a systematic comparison and analysis of four discrete-time,
host--parasitoid models. For each model, we specify that density-dependent
effects occur prior to parasitism in the life cycle of the host. We compare
density-dependent growth functions arising from the Beverton--Holt and Ricker
maps, as well as parasitism functions assuming either a Poisson or negative
binomial distribution for parasitoid attacks. We show that overcompensatory
density-dependence leads to period-doubling bifurcations, which may be
supercritical or subcritical. Stronger parasitism from the Poisson distribution
leads to loss of stability of the coexistence equilibrium through a
Neimark--Sacker bifurcation, resulting in population cycles. Our analytic
results also revealed dynamics for one of our models that were previously
undetected by authors who conducted a numerical investigation. Finally, we
emphasize the importance of clearly presenting biological assumptions that are
inherent to the structure of a discrete-time model in order to promote
communication and broader understanding.
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We propose RecSim, a configurable platform for authoring simulation
environments for recommender systems (RSs) that naturally supports sequential
interaction with users. RecSim allows the creation of new environments that
reflect particular aspects of user behavior and item structure at a level of
abstraction well-suited to pushing the limits of current reinforcement learning
(RL) and RS techniques in sequential interactive recommendation problems.
Environments can be easily configured that vary assumptions about: user
preferences and item familiarity; user latent state and its dynamics; and
choice models and other user response behavior. We outline how RecSim offers
value to RL and RS researchers and practitioners, and how it can serve as a
vehicle for academic-industrial collaboration.
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The Kerr spacetime of spinning black holes is one of the most intriguing
predictions of Einstein's theory of general relativity. The special role this
spacetime plays in the theory of gravity is encapsulated in the no-hair
theorem, which states that the Kerr metric is the only realistic black-hole
solution of the vacuum field equations. Recent and anticipated advances in the
observations of black holes throughout the electromagnetic spectrum have
secured our understanding of their basic properties while opening up new
opportunities for devising tests of the Kerr metric. In this paper, we argue
that imaging and spectroscopic observations of accreting black-holes with
current and future instruments can lead to the first direct test of the no-hair
theorem.
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Truly unfortunate situations, for life can hand us a rotten deal; but should the child pay the price? No. A woman who is a product of a rape travels the country speaking about how grateful she is her mother did not kill her. We must sometimes take a higher, more difficult road for the good of another.
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You mentioned government interference, so lets go there. Look at the deed to your house. The grants you that land for $1 plus additional considerations and you pay annual rent in taxes for government wealth (paid to contrcution companies who build wealth by doing so) in the form of roads and water and sewage systems. You buy stuff because inventors have patents from the goverment so they can enforce their ownership rights. You have life saving drugs because drug makers used research funded by the government. This Internet thing? The web was originally a project called DARPANET. I saw it when I was a AF civil servant before the graphics, back in 86. Look at your money. Government scrip. The fact that you can accumulate wealth comes in part because your parents have or had government retirement. Every fly? Odds are the jet you flew was first developed as an AF tanker. Like eating? Goverment price floors make sure there is a surplus of basic staples.
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We review the F(R) supergravity recently proposed in Phys. Lett. B674 (2009)
59 and Class. Quantum Grav. 26 (2009) 135006. Our construction supersymmetrizes
popular f(R) theories of modified gravity in four spacetime dimensions. We use
curved superspace of N=1 Poincar'e supergravity in its minimal (2nd order)
formulation so that our F(R) supergravity action is manifestly invariant under
local N=1 supersymmetry. We prove that the F(R) supergravity is classically
equivalent to the standard N=1 Poincar'e supergravity (minimally) coupled to a
dynamical chiral superfield, via a Legendre-Weyl transform in superspace. A
K"ahler potential, a superpotential and a scalar potential of the chiral
superfield are governed by a single holomorphic function. We find the
conditions of vanishing cosmological constant without fine-tuning, which define
a no-scale F(R) supergravity.
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In this paper the problem of recovering an algebraic dynamics in a
perturbative approach is discussed. The mathematical environment in which the
physical problem is considered is that of algebras of unbounded operators
endowed with the quasi-uniform topology. After some remarks on the domain of
the perturbation, conditions are given for the dynamics to exist as the limit
of a net of regularized linear maps.
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Obviously the GET tax would be better as tourists would also pay. We need to get this built. A full investigation needs to be done on why the costs have escalated so much. Not sure what can be done about it but if it is due largely to delays, well, one should think twice before listening to such people in the future who are only negative.
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The recently established universal uncertainty principle revealed that two
nowhere commuting observables can be measured simultaneously in some state,
whereas they have no joint probability distribution in any state. Thus, one
measuring apparatus can simultaneously measure two observables that have no
simultaneous reality. In order to reconcile this discrepancy, an approach based
on quantum logic is proposed to establish the relation between quantum reality
and measurement. We provide a language speaking of values of observables
independent of measurement based on quantum logic and we construct in this
language the state-dependent notions of joint determinateness, value identity,
and simultaneous measurability. This naturally provides a contextual
interpretation, in which we can safely claim such a statement that one
measuring apparatus measures one observable in one context and simultaneously
it measures another nowhere commuting observable in another incompatible
context.
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Natural wood watch face is nice
I love the wooden watch face with hour markers. I don't like the cheap looking band and will be replacing it. Keeps time nicely and not too big for a female wrist. If the band were not so chintzy I would have rated it higher.
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Ugh!
I order these as a gift. They only sent me one. I contacted Amazon and they sent me two in the mail, but having never returned anything through amazon before, I had asked if they will send me a return mail label, they said yes, but I never got it, so the "one" they sent me, when they should have sent "two" (in my initial order) sat in my spare bedroom with all the other Christmas mess and now I have been charged for "two" again. I have exhausted myself trying to get a message back to Amazon to see if I could still return, and if not, could they at least send me the missing "bag" from the "initial order", since they are making me pay for it, but have been unable to get this message relayed - exhausting and aggravating!! Other than that, the bags looked great.
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Good when they work but .....
I purchased one of the lights just to see how it worked! It seemed fine so I bought 3 more! A week later I am finding that the connection to the Wi-Fi keeps getting lost and then will not recover. So I have to keep resetting the bulbs and then reconnect them to the internet. This is Not what I was looking for. When the lights work, they are great but so far all they have done is convince me to invest in a Phillips hue system!!
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Gradient descent finds a global minimum in training deep neural networks
despite the objective function being non-convex. The current paper proves
gradient descent achieves zero training loss in polynomial time for a deep
over-parameterized neural network with residual connections (ResNet). Our
analysis relies on the particular structure of the Gram matrix induced by the
neural network architecture. This structure allows us to show the Gram matrix
is stable throughout the training process and this stability implies the global
optimality of the gradient descent algorithm. We further extend our analysis to
deep residual convolutional neural networks and obtain a similar convergence
result.
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Too heavy for helium
Bought for a balloon release for my dad and grandpa on father's day. Very heavy material which I thought would mean they were durable, but actually it's just too heavy to float. We checked the helium we bought separately on a standard latex balloon and it flew fine so it was definitely these balloons unfortunately. We had to break a seal in order to inflate them at all, idk if that's standard but seemed strange to me. Return started.
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I couldn't believe I spent $14.00 on this. The only redeeming quality is the outrageous gore. The dubbing was worse than any I have ever experienced. It looks like it was shot with a VHS camcorder. I think every pfennig was spent on the special effects because there was a whole lot of blood and body parts everywhere. Its one of the worst movies I have ever seen but I do have to acknowledge the plentiful gore that wasn't as disgusting as it could have been because the whole movie is so silly and unbelievable
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Pocho do you have a reading comprehension problem? Where did I say that there was any terror committed by the KKK? I said that the vast MAJORITY of terrorist shootings/bombings etc... in this country since 9/11 were perpetrated by RIGHT WING "Christian" extremists. Since 9/11 there were 21 instances of right-wing, white extremist, "Christian" terrorist attacks in the U.S. that caused 53 fatalities....
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The lateral hypothalamic area (LHA) regulates food intake and energy expenditure. Although LHA neurons innervate adipose tissues, the identity of neurons that regulate fat is undefined. Here we identify that Gabra5-positive neurons in LHA (GABRA5LHA) polysynaptically project to brown and white adipose tissues in the periphery. GABRA5LHA are a distinct subpopulation of GABAergic neurons and show decreased pacemaker firing in diet-induced obesity (DIO) mouse model. Chemogenetic inhibition of GABRA5LHA suppresses energy expenditure and increases weight gain, whereas gene-silencing of Gabra5 in LHA decreases weight gain. In DIO mouse model, GABRA5LHA are tonically inhibited by nearby reactive astrocytes releasing GABA, which is synthesized by MAOB. Gene-silencing of astrocytic MAOB in LHA reduces weight gain significantly without affecting food intake, which is recapitulated by administration of a MAOB inhibitor, KDS2010. We propose that firing of GABRA5LHA facilitates energy expenditure and selective inhibition of astrocytic GABA is a molecular target for treating obesity.
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We investigate the complexity of the Boolean clone membership problem (CMP):
given a set of Boolean functions $F$ and a Boolean function $f$, determine if
$f$ is in the clone generated by $F$, i.e., if it can be expressed by a circuit
with $F$-gates. Here, $f$ and elements of $F$ are given as circuits or formulas
over the usual De Morgan basis. B\"ohler and Schnoor (2007) proved that for any
fixed $F$, the problem is coNP-complete, with a few exceptions where it is in
P. Vollmer (2009) incorrectly claimed that the full problem CMP is also
coNP-complete. We prove that CMP is in fact $\Theta^P_2$-complete, and we
complement B\"ohler and Schnoor's results by showing that for fixed $f$, the
problem is NP-complete unless $f$ is a projection.
More generally, we study the problem $B$-CMP where $F$ and $f$ are given by
circuits using gates from $B$. For most choices of $B$, we classify the
complexity of $B$-CMP as being $\Theta^P_2$-complete (possibly under randomized
reductions), coDP-complete, or in P.
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Recent advances in artificial intelligence have been strongly driven by the
use of game environments for training and evaluating agents. Games are often
accessible and versatile, with well-defined state-transitions and goals
allowing for intensive training and experimentation. However, agents trained in
a particular environment are usually tested on the same or slightly varied
distributions, and solutions do not necessarily imply any understanding. If we
want AI systems that can model and understand their environment, we need
environments that explicitly test for this. Inspired by the extensive
literature on animal cognition, we present an environment that keeps all the
positive elements of standard gaming environments, but is explicitly designed
for the testing of animal-like artificial cognition.
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This study presents the investigation of the connection between radial
electric field, gradient of Reynolds stress and Long Range Correlation (LRC),
as a proxy for Zonal Flows (ZF), in different plasma scenarios in the TJ-II
stellarator. Monte Carlo simulations were made showing that radial electric
fields in the range of those experimentally measured have an effect on the
neoclassical orbit losses. The results indicate that, despite the order of
magnitude of turbulent acceleration is comparable to the neoclassical damping
of perpendicular flows, its dependence with radial electric field is not
correlated with the evolution of LRC amplitude, indicating that turbulent
acceleration alone cannot explain the dynamics of Zonal Flows. These results
are in line with the expectation that the interplay between turbulent and
neoclassical mechanisms is a crucial ingredient of the dynamics of edge Zonal
Flows.
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We discuss the use of parametric phase-diverse phase retrieval as an in-situ
high-fidelity wavefront measurement method to characterize and optimize the
transmitted wavefront of a high-contrast coronagraphic instrument. We apply our
method to correct the transmitted wavefront of the HiCAT (High contrast imager
for Complex Aperture Telescopes) coronagraphic testbed. This correction
requires a series of calibration steps, which we describe. The correction
improves the system wavefront from 16 nm RMS to 3.0 nm RMS.
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We study the properties of graphene wormholes in which a short nanotube acts
as a bridge between two graphene sheets, where the honeycomb carbon lattice is
curved from the presence of 12 heptagonal defects. By taking the nanotube
bridge with very small length compared to the radius, we develop an effective
theory of Dirac fermions to account for the low-energy electronic properties of
the wormholes in the continuum limit, where the frustration induced by the
heptagonal defects is mimicked by a line of fictitious gauge flux attached to
each of them. We find in particular that, when the effective gauge flux from
the topological defects becomes maximal, the zero-energy modes of the Dirac
equation can be arranged into two triplets, that can be thought as the
counterpart of the two triplets of zero modes that arise in the dual instance
of the continuum limit of large spherical fullerenes. We further investigate
the graphene wormhole spectra by performing a numerical diagonalization of
tight-binding hamiltonians for very large lattices realizing the wormhole
geometry. The correspondence between the number of localized electronic states
observed in the numerical approach and the effective gauge flux predicted in
the continuum limit shows that graphene wormholes can be consistently described
by an effective theory of two Dirac fermion fields in the curved geometry of
the wormhole, opening the possibility of using real samples of the carbon
material as a playground to experiment with the interaction between the
background curvature and the Dirac fields.
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The prospect of detecting relic gravitational waves (RGWs), through their
imprint in the cosmic microwave background radiation, provides an excellent
opportunity to study the very early Universe. In simplest viable theoretical
models the RGW background is characterized by two parameters, the
tensor-to-scalar ratio $r$ and the tensor spectral index $n_t$. In this paper,
we analyze the potential joint constraints on these two parameters, $r$ and
$n_t$, using the data from the upcoming cosmic microwave background radiation
experiments. Introducing the notion of the best pivot multipole $\ell_t^*$, we
find that at this pivot multipole the parameters $r$ and $n_t$ are
uncorrelated, and have the smallest variances. We derive the analytical
formulae for the best pivot multipole number $\ell_t^*$, and the variances of
the parameters $r$ and $n_t$. We verify these analytical calculations using
numerical simulation methods, and find agreement to within 20%. The analytical
results provides a simple way to estimate the detection ability for the relic
gravitational waves by the future observations of the cosmic microwave
background radiation.
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We show that strong-coupling (SC) of light and matter as it is realized with
quantum dots (QDs) in microcavities differs substantially from the paradigm of
atoms in optical cavities. The type of pumping used in semiconductors yields
new criteria to achieve SC, with situations where the pump hinders, or on the
contrary, favours it. We analyze one of the seminal experimental observation of
SC of a QD in a pillar microcavity [Reithmaier et al., Nature (2004)] as an
illustration of our main statements.
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The large and growing library of measurements from the Large Hadron Collider
has significant power to constrain extensions of the Standard Model. We
consider such constraints on a well-motivated model involving a gauged and
spontaneously-broken $B-L$ symmetry, within the Contur framework. The model
contains an extra Higgs boson, a gauge boson, and right-handed neutrinos with
Majorana masses. This new particle content implies a varied phenomenology
highly dependent on the parameters of the model, very well-suited to a general
study of this kind. We find that existing LHC measurements significantly
constrain the model in interesting regions of parameter space. Other regions
remain open, some of which are within reach of future LHC data.
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The factors limiting the resolution of displacement sensor based on extrinsic
Fabry-Perot interferometer were studied. An analytical model giving the
dependency of EFPI resolution on the parameters of an optical setup and a
sensor interrogator was developed. The proposed model enables one to either
estimate the limit of possible resolution achievable with a given setup, or to
derive the requirements for optical elements and/or a sensor interrogator
necessary for attaining the desired sensor resolution. An experiment supporting
the analytical derivations was performed, demonstrating a large dynamic
measurement range (with cavity length from tens microns to 5 mm), a high
baseline resolution (from 14 pm) and a good agreement with the model.
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Edges chip off and leave jagged edges.
The edges of this screen protector completely chip off and leave jagged edges. This the second one I've applied in 2 weeks with the same results. When I remove it, the watch screen is perfectly in tact. So I suppose it's doing it's job. If you're a delicate flower and don't bang into things, you'll probably be fine with this protector. But then again, you probably don't even need one in that case.
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And you point is? Some things heal slowly. If you really step back the World Crisis for lack of a better word can be tied back the America cultivation and encouragement of violent jihad Islam to use against the Russians in Afghanistan. The world is still paying for that, and looking back we now know it would have been far better to let the Russians keep the pro Russian Kabul regime in place. What came after proves it. Unfortunately the foreign policy thinkers in America are still doubling down in the destructive American/Wahhabi alliance. It's tragic and lethal.
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The question whether ferroelectricity (FE) may coexist with a metallic or
highly conducting state, or rather it must be suppressed by the screening from
the free charges, is the focus of a rapidly increasing number of theoretical
studies and is finally receiving positive experimental responses. The issue is
closely related to the thermoelectric and multiferroic (also magnetic)
applications of FE materials, where the electrical conductivity is required or
spurious. In these circumstances, the traditional methods for probing
ferroelectricity are hampered or made totally ineffective by the free charges,
which screen the polar response to an external electric field. This fact may
explain why more than 40 years passed between the first proposals of FE metals
and the present experimental and theoretical activity. The measurement of the
elastic moduli, Young's modulus in the present case, versus temperature is an
effective method for studying the influence of doping on a FE transition
because the elastic properties are unaffected by electrical conductivity. In
this manner, it is shown that the FE transitions of BaTiO3-d are not suppressed
by electron doping through O vacancies; only the onset temperatures are
depressed, but the magnitudes of the softenings, and hence of the piezoelectric
activity, are initially even increased.
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Good price, but not very durable.
I had high hopes for this product after seeing the price and all the good reviews, but unfortunately, the gloves I got did not last a month. They held up ok for about 2.5 weeks, but then holes started appearing. I hate to give a black mark, but the gloves- while comfortable and great fitting- fell short on durability which is the one aspect that I had the highest hopes for.
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The Chiral Perturbation Theory (ChPT) has been very successful in describing
low-energy hadronic properties in the non-perturbative regime of Quantum
Chromodynamics. The results of ChPT, many of which are currently under active
experimental investigation, provide stringent predictions of many fundamental
properties of hadrons, including quantities such as electromagnetic
polarizabilities. The paper outlines our semi-automated calculations in ChPT,
the corresponding results for the electric and magnetic polarizabilities of the
proton and our predictions for Compton differential cross sections.
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We introduce a continuum of dimensions which are `intermediate' between the
familiar Hausdorff and box dimensions. This is done by restricting the families
of allowable covers in the definition of Hausdorff dimension by insisting that
$|U| \leq |V|^\theta$ for all sets $U, V$ used in a particular cover, where
$\theta \in [0,1]$ is a parameter. Thus, when $\theta=1$ only covers using sets
of the same size are allowable, and we recover the box dimensions, and when
$\theta=0$ there are no restrictions, and we recover Hausdorff dimension.
We investigate many properties of the intermediate dimension (as a function
of $\theta$), including proving that it is continuous on $(0,1]$ but not
necessarily continuous at $0$, as well as establishing appropriate analogues of
the mass distribution principle, Frostman's lemma, and the dimension formulae
for products. We also compute, or estimate, the intermediate dimensions of some
familiar sets, including sequences formed by negative powers of integers, and
Bedford-McMullen carpets.
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We study quantum entanglements induced on product states by the action of
8-vertex braid matrices, rendered unitary with purely imaginary spectral
parameters (rapidity). The unitarity is displayed via the "canonical
factorization" of the coefficients of the projectors spanning the basis. This
adds one more new facet to the famous and fascinating features of the 8-vertex
model. The double periodicity and the analytic properties of the elliptic
functions involved lead to a rich structure of the 3-tangle quantifying the
entanglement. We thus explore the complex relationship between topological and
quantum entanglement.
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Despite over two decades of intense research efforts, the origin of
high-temperature superconductivity in the copper oxides remains elusive.
Angle-resolved photoemission experiments (ARPES) revealed a kink in the
dispersion relations (energy vs. wavevector) of electronic states in the
cuprates at binding energies of 50-80 meV, and raised the hope that this
anomaly could be key to understanding high-temperature superconductivity. The
kink is often interpreted in terms of interactions between the electrons and a
bosonic field. While there is no consensus on the nature of the bosons or even
whether a boson model is appropriate, phonons and spin fluctuations have
alternatively been proposed as possible candidates. Here we report
state-of-the-art first-principles calculations of the role of phonons and the
electron-phonon interaction in the photoemission spectra of La2-xSrxCuO4
(LSCO). Our study demonstrates that the phonon-induced renormalization of the
electron energies and the Fermi velocity is almost one order of magnitude
smaller than the effect observed in photoemission experiments. Hence, the
present finding rules out electron-phonon interaction in bulk LSCO as the
possible origin of the measured kink. This result should bear on several
proposed theories of high temperature superconductivity in addition to theories
concerning the origin of kinks in cuprate photoemission data.
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Despite the improvements in perception accuracies brought about via deep
learning, developing systems combining accurate visual perception with the
ability to reason over the visual percepts remains extremely challenging. A
particular application area of interest from an accessibility perspective is
that of reasoning over statistical charts such as bar and pie charts. To this
end, we formulate the problem of reasoning over statistical charts as a
classification task using MAC-Networks to give answers from a predefined
vocabulary of generic answers. Additionally, we enhance the capabilities of
MAC-Networks to give chart-specific answers to open-ended questions by
replacing the classification layer by a regression layer to localize the
textual answers present over the images. We call our network ChartNet, and
demonstrate its efficacy on predicting both in vocabulary and out of vocabulary
answers. To test our methods, we generated our own dataset of statistical chart
images and corresponding question answer pairs. Results show that ChartNet
consistently outperform other state-of-the-art methods on reasoning over these
questions and may be a viable candidate for applications containing images of
statistical charts.
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The X(3872) is studied as an axial-vector charmonium state in the
multichannel framework of the Resonance-Spectrum-Expansion quark-meson model,
previously applied to a variety of other puzzling mesonic resonances. Included
are the open-charm pseudoscalar-vector and vector-vector channels, the most
important of which is the S-wave $\bar{D}^{*0}D^{0}$ + $D^{*0}\bar{D}^{0}$
channel, which practically coincides with the X(3872) structure. The two free
parameters of the model are tuned so as to roughly reproduce the
$\chi_{c1}(3511)$ mass as well as the enhancement just above the
$\bar{D}^{*0}D^{0}$ / $D^{*0}\bar{D}^{0}$ threshold. The present model is able
to describe the shape of the latter data quite well. However, as no dynamical
resonance pole is found, the X(3872) and X(3940) cannot be reproduced
simultaneously, at this stage. A possible further improvement is discussed.
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Quantum walk research has mainly focused on evolutions due to repeated
applications of time-independent unitary coin operators. However, the idea of
controlling the single particle evolution using time-dependent unitary coins
has still been a subject of multiple studies as it not only hosts interesting
possibilities for quantum information processing but also opens a much richer
array of phenomena including static and dynamic localizations. So far, such
studies have been performed only for single quantum walkers. In case of
multi-walker systems, time-dependent coins may generate measurable phenomena
not described by the single-particle model, due to entanglement and interaction
among the walkers. In this context, we present here a thorough numerical study
of an one dimensional system of two quantum walkers exhibiting rich collective
dynamics controlled by simple time-dependent unitary coins proposed in [Phys.
Rev. A \textbf{80}, 042332(2009)] and [Phys. Rev. A \textbf{73},062304(2006)].
We study how the interplay of coin time-dependence, simple interaction schemes,
entanglement and the relative phase between the coin states of the particles
influences the evolution of the quantum walk. The results show that the system
offers a rich variety of collective dynamical behavior while being controlled
by time dependent coins. In particular, we find and characterize fascinating
two-body localization phenomena with tunable quasiperiodic dynamics of
correlations and entanglements which are quantities of quantum origin.
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We study a modified version of a model previously proposed by Jackson and
Wolinsky to account for communicating information and allocating goods in
socioeconomic networks. In the model, the utility function of each node is
given by a weighted sum of contributions from all accessible nodes. The
weights, parameterized by the variable $\delta$, decrease with distance. We
introduce a growth mechanism where new nodes attach to the existing network
preferentially by utility. By increasing $\delta$, the network structure
evolves from a power-law to an exponential degree distribution, passing through
a regime characterised by shorter average path length, lower degree
assortativity and higher central point dominance. In the second part of the
paper we compare different network structures in terms of the average utility
received by each node. We show that power-law networks provide higher average
utility than Poisson random networks. This provides a possible justification
for the ubiquitousness of scale-free networks in the real world.
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We demonstrate the generation of vortex solitons in a model of dissipative
optical media with the singular anti-cubic (AC) nonlinearity, by launching a
vorticity-carrying Gaussian input into the medium modeled by the cubic-quintic
complex Ginzburg-Landau equation with the additional AC term. The effect of the
latter term on the beam propagation is investigated in detail. An analytical
result is produced for the asymptotic form of fundamental and vortical solitons
at r --> 0, which is determined by the AC term. Numerical simulations identify
parameter domains which maintain stable dissipative solitons in the form of
vortex clusters. The number of vortices in the clusters is equal to the
vorticity embedded in the Gaussian input.
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This is a disappointing adaptation of the James Lee Burke novel "In the Electric Mist of the Confederate Dead". It is rather poorly acted mainly due to the miscasting of the principal players. Tommy Lee Jones, a normally fine actor, just doesn't capture Burke's "Dave Robicheaux". As Robicheaux's main nemesis, John Goodman does a sloppy job as the "heavy". The guy who plays Robicheaux's actor-buddy doesn't look like a former "A" lister leading man. The rest of the movie is mainly cast with no-name locals who just don't do justice to a big-time novel.<br /><br />The movie and Jones' performance is way too hurried for one thing. Robicheaux in Burke's series of novels, gives one the feeling that he fits well into his environment most of the time, being laid back and slow-moving. This is just like the deep south and southern Louisiana. Then at times Robicheaux is nearly manic in his exertions. Jones just moves at a fast pace through the whole movie. He doesn't vary. Ned Beatty is wasted. Mary Steenburgen is out of place. About the only good thing about this is the setting. On the whole the movie gives one the impression of a TV movie.
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I find Hillary Clinton matching each and every element, as well. D
Disregard of feelings of others: See Jennifer Flowers, Monica Lewinski attacks.
Lack of remorse or shame: See above and Benghazi.
Manipulative behavior: Her entire political career has been devoted to that.
Unchecked egocentricity: Hillary 1st, last and always.
Lie to achieve one's goals: FBI Director is only the latest example.
These are the two best Presidential candidates in the United States of America.
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I like all different types of movies, so this is not a bash on romantic movies from a guy who only likes The Matrix etc etc.<br /><br />I just felt it was a lousy movie. I don't feel that there was enough buildup of the characters to fall in love. They were there for a few days and while dealing with a severe hurricane and major issues in each of their lives, Richard Gere and Diane Lane fall hopelessly and helplessly in love?? It isn't realistic. This movie didn't make me buy into it and feel it emotionally and that is something that you look for in a good plot. Some emotional connection. If someone can relate to them falling in love that quickly, without any true substance , than so be it. You are neither right or wrong. Different strokes for different folks.<br /><br />Another very unbelievable component to the movie was Diane Lane's very rude teenage daughter becoming nice and sympathetic at the end of the movie. Does a teenage girl who is that miserable and aggravated at her mother for not getting back with her cheating husband going to just have a switch turn on and be nice? This movie, in a nutshell, had some big names, but to me, was a major disappointment.
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Surely US allies are not stupid enough to believe that Trump is anything but erratic and irrational? Any other belief is just wishful thinking. Remember where wishful thinking got the world with George W. Bush. Sometimes it is just necessary to accept that the US President is every bit as incompetent as he appears to be
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We introduce a deep convolutional neural networks (CNN) architecture to
classify facial attributes and recognize face images simultaneously via a
shared learning paradigm to improve the accuracy for facial attribute
prediction and face recognition performance. In this method, we use facial
attributes as an auxiliary source of information to assist CNN features
extracted from the face images to improve the face recognition performance.
Specifically, we use a shared CNN architecture that jointly predicts facial
attributes and recognize face images simultaneously via a shared learning
parameters, and then we use facial attribute features an an auxiliary source of
information concatenated by face features to increase the discrimination of the
CNN for face recognition. This process assists the CNN classifier to better
recognize face images. The experimental results show that our model increases
both the face recognition and facial attribute prediction performance,
especially for the identity attributes such as gender and race. We evaluated
our method on several standard datasets labeled by identities and face
attributes and the results show that the proposed method outperforms
state-of-the-art face recognition models.
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Physical systems with discrete energy levels are ubiquitous in nature and are
fundamental building blocks of quantum technology. Realizing controllable
artifcial atom- and molecule-like systems for light would allow for coherent
and dynamic control of the frequency, amplitude and phase of photons. In this
work, we demonstrate a photonic molecule with two distinct energy-levels and
control it by external microwave excitation. We show signature two-level
dynamics including microwave induced photonic Autler-Townes splitting, Stark
shift, Rabi oscillation and Ramsey interference. Leveraging the coherent
control of optical energy, we show on-demand photon storage and retrieval in
optical microresonators by reconfguring the photonic molecule into a
bright-dark mode pair. These results of dynamic control of light in a
programmable and scalable electro-optic platform open doors to applications in
microwave photonic signal processing, quantum photonics in the frequency
domain, optical computing concepts and simulations of complex physical systems.
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The author offers a new kind of thermonuclear reflect reactor. The remarkable
feature of this new reactor is a three net AB reflector, which confines the
high temperature plasma. The plasma loses part of its energy when it contacts
with the net but this loss can be compensated by an additional permanent plasma
heating. When the plasma is rarefied (has a small density), the heat flow to
the AB reflector is not large and the temperature in the triple reflector net
is lower than 2000 - 3000 K. This offered AB-reactor has significantly less
power then the currently contemplated power reactors with magnetic or inertial
confinement (hundreds-thousands of kW, not millions of kW). But it is enough
for many vehicles and ships and particularly valuable for tunnelers, subs and
space apparatus, where air to burn chemical fuel is at a premium or simply not
available.
The author has made a number of innovations in this reactor, researched its
theory, developed methods of computation, made a sample computation of typical
project. The main point of preference for the offered reactor is its likely
cheapness as a power source.
Key words: Micro-thermonuclear reactor, Multi-reflex AB-thermonuclear
reactor, Self-magnetic AB-thermonuclear reactor, aerospace thermonuclear
engine.
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Since early 2021, SARS-CoV-2 variants of concern (VOCs) have been causing epidemic rebounds in many countries. Their properties are well characterised at the epidemiological level but the potential underlying within-host determinants remain poorly understood. We analyse a longitudinal cohort of 6,944 individuals with 14,304 cycle threshold (Ct) values of qPCR VOC screening tests performed in the general population and hospitals in France between February 6 and August 21, 2021. To convert Ct values into numbers of virus copies, we performed an additional analysis using droplet digital PCR (ddPCR). We find that the number of viral genome copies reaches a higher peak value and has a slower decay rate in infections caused by Alpha variant compared to that caused by historical lineages. Following the evidence that viral genome copies in upper respiratory tract swabs are informative on contagiousness, we show that the kinetics of the Alpha variant translate into significantly higher transmission potentials, especially in older populations. Finally, comparing infections caused by the Alpha and Delta variants, we find no significant difference in the peak viral copy number. These results highlight that some of the differences between variants may be detected in virus load variations.
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I had the great pleasure of recently viewing this beautifully filmed wide-screen adaption of the the 1943 stage revival (which unlike the original 1935 production) which included extensive spoken recitatives. This had been the fashion at the time, so to blame the film for an 16 year tradition. The film should be seen if only for Sammy Davis Jrs brilliant catlike performance as Sportin' Life, creeping in and out of shadows. His seduction of Dorothy Dadridge's BESS "There's a Boat dat's leavin' soon for New York," is one of many highlights. Nearly all of the principal music is intact and beautifully sung. It certainly never bores which the recent PBS and MET versions did. It was a pleasure to see that time had not diminished the movie, and hopefully it will be made available in the near future for the generations that haven't had a chance to experience it.
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The general theory of relativity is used to show that the total energy-mass
of the visible Universe could be produced by an energy-mass source with the
Planck power. The source was supposedly born at the phase of cosmic inflation
and acts continuously throughout the lifetime of our Universe. The model allows
one to treat dark energy as a real form of energy without using the hypothesis
of anti-gravity.
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We introduce the construction of a orthogonal wavepacket basis set, using the
concept of stroboscopic time propagation, tailored to the efficient description
of non-equilibrium extended electronic systems. Thanks to three desirable
properties of this basis, significant insight is provided into non-equilibrium
processes (both time-dependent and steady-state), and reliable physical
estimates of various many-electron quantities such as density, current and spin
polarization can be obtained. The use of this novel tool is demonstrated for
time-dependent switching-on of the bias in quantum transport, and new results
are obtained for current-induced spin accumulation at the edge of a 2D doped
semiconductor caused by edge-induced spin-orbit interaction.
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We derive a unique continuation theorem for the vacuum Einstein equations.
Our method of proof utilizes Carleman estimates (most importantly one obtained
recently by Ionescu and Klainerman), but also relies strongly on certain
geometric gauge constructions which make it possible to address this problem
via such estimates. We indicate how our method can be used more broadly to
derive unique continuation for Einstein's equations from Carleman estimates for
the wave operator.
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Metal-semiconductor interfaces, known as Schottky junctions, have long been
hindered by defects and impurities. Such imperfections dominate the electrical
characteristics of the junction by pinning the metal Fermi energy. We report
measurements on a boron nitride encapsulated graphene-tungsten diselenide
(WSe$_2$) Schottky junction which exhibits ideal diode characteristics and a
complete lack of Fermi-level pinning. The Schottky barrier height of the device
is rigidly tuned by electrostatic gating of the WSe$_2$, enabling experimental
verification of the Schottky-Mott limit in a single device. Utilizing this
exceptional gate control, we realize a super-ideal gated-Schottky diode which
surpasses the ideal diode limit. Our results provide a pathway for defect-free
electrical contact to two-dimensional semiconductors and open up possibilities
for circuits with efficient switching characteristics and higher efficiency
optoelectronic devices.
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A novel permutation decoding method for Reed-Muller codes is presented. The
complexity and the error correction performance of the suggested permutation
decoding approach are similar to that of the recursive lists decoder. It is
demonstrated that the proposed decoding technique can take advantage of several
early termination methods leading to a significant reduction of the operations
number required for the decoding, with the error correction performance being
the same.
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Accurate control of quantum systems requires precise measurement of the
parameters that govern the dynamics, including control fields and interactions
with the environment. Parameters will drift in time and experiments interleave
protocols that perform parameter estimation with protocols that measure the
dynamics of interest. Here we specialize to a system made of qubits where the
dynamics correspond to a quantum computation. We propose setting aside some
qubits, which we call spectator qubits, to be measured periodically during the
computation, to act as probes of the changing experimental and environmental
parameters. By using control strategies that minimize the sensitivity of the
qubits involved in the computation, we can acquire sufficient information from
the spectator qubits to update our estimates of the parameters and improve our
control. As a result, we can increase the length of experiment where the
dynamics of the data qubits are highly reliable. In particular, we simulate how
spectator qubits can keep the error level of operations on data qubits below a
$10^{-4}$ threshold in two scenarios involving coherent errors: a classical
magnetic field gradient dynamically decoupled with sequences of two or four
$\pi$-pulses, and laser beam instability detected via crosstalk with
neighboring atoms in an ion trap.
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The last few years have seen an explosion of academic and popular interest in
algorithmic fairness. Despite this interest and the volume and velocity of work
that has been produced recently, the fundamental science of fairness in machine
learning is still in a nascent state. In March 2018, we convened a group of
experts as part of a CCC visioning workshop to assess the state of the field,
and distill the most promising research directions going forward. This report
summarizes the findings of that workshop. Along the way, it surveys recent
theoretical work in the field and points towards promising directions for
research.
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An elliptic curve-based signcryption scheme is introduced in this paper that
effectively combines the functionalities of digital signature and encryption,
and decreases the computational costs and communication overheads in comparison
with the traditional signature-then-encryption schemes. It simultaneously
provides the attributes of message confidentiality, authentication, integrity,
unforgeability, non-repudiation, public verifiability, and forward secrecy of
message confidentiality. Since it is based on elliptic curves and can use any
fast and secure symmetric algorithm for encrypting messages, it has great
advantages to be used for security establishments in store-and-forward
applications and when dealing with resource-constrained devices.
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We have proposed a density-matrix renormalization group (DMRG) scheme to
optimize the one-electron basis states of molecules. It improves significantly
the accuracy and efficiency of the DMRG in the study of quantum chemistry or
other many-fermion system with nonlocal interactions. For a water molecule, we
find that the ground state energy obtained by the DMRG with only 61 optimized
orbitals already reaches the accuracy of best quantum Monte Carlo calculation
with 92 orbitals.
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It works.. some times.
The first night I slept great! I was ecstatic! The second night, however, I went back to my old routine and couldn't sleep at all. I thought it was a fluke and tried it again.. Essentially, it works some times. Other times, I lay awake and can't sleep. Not good enough for something so pricey.
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The solution of the axial U(1) problem, the role of the topology of the gauge
group in forcing the breaking of axial symmetry in any irreducible
representation of the observable algebra and the theta vacua structure are
revisited in the temporal gauge with attention to the mathematical consistency
of the derivations. Both realizations with strong and weak Gauss law are
discussed; the control of the general mechanisms and structures is obtained on
the basis of the localization of the (large) gauge transformations and the
local generation of the chiral symmetry. The Schwinger model in the temporal
gauge exactly reproduces the general results.
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