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recent research has exposed disagreements over the nature and usefulness of what may ( or may not ) be human - computer interaction ' s fundamental phenomenon : ' interaction '. for some, hci ' s theorising about interaction has been deficient, impacting its capacity to inform decisions in design, suggesting the need either to perform first - principles definition work or broader administrative clarification and formalisation of the multitude of formulations of the concepts of interaction and their particular uses. for others, there remain open questions over the continued relevance of certain ' versions ' of interaction as a useful concept in hci at all. we pursue a different perspective in this paper, reviewing how hci treats interaction through examining its ' conceptual pragmatics ' within hci ' s discourse. we argue that articulations of the concepts of interaction can be a site of productive conflict for hci that for many reasons may resist attempts of formalisation as well as attempts to dispense with them. the main contribution of this paper is in specifying how we might go about talking of interaction and the value of interaction language as promiscuous concepts. | arxiv:1903.03446 |
in this paper we analyse the relations between a previously described oblate jaffe model for an ellipsoidal galaxy and the observed quantities for ngc 2974, and obtain the length and velocity scales for a relevant elliptical galaxy model. we then derive the finite total mass of the model from these scales, and finally find a good fit of an isotropic oblate jaffe model by using the gauss - hermite fit parameters and the observed ellipticity of the galaxy ngc 2974. the model is also used to predict the total luminous mass of ngc 2974, assuming that the influence of dark matter in this galaxy on the image, ellipticity and gauss - hermite fit parameters of this galaxy is negligible within the central region, of radius $ 0. 5r _ { \ rm e }. $ | arxiv:0810.3404 |
in order to give the standard scenario of the astrophysics, we study the einstein theory with minimally coupled scalar field and the cosmological term by considering the scalar field as a candidate of the dark matter. we obtained the exact solution in the cosmological scale and the approximate gravitational potential in the galactic or solar scale. we find that the scalar field plays the role of the dark matter in some sense in the cosmological scale but it does not play the role of the dark matter in the galactic or solar scale within our approximation. | arxiv:gr-qc/0003062 |
the baer - - suzuki theorem says that if $ p $ is a prime, $ x $ is a $ p $ - element in a finite group $ g $ and $ \ langle x, x ^ g \ rangle $ is a $ p $ - group for all $ g \ in g $, then the normal closure of $ x $ in $ g $ is a $ p $ - group. we consider the case where $ x ^ g $ is replaced by $ y ^ g $ for some other $ p $ - element $ y $. while the analog of baer - - suzuki is not true, we show that some variation is. we also answer a closely related question of pavel shumyatsky on commutators of conjugacy classes of $ p $ - elements. | arxiv:1310.5909 |
we discuss the canonical quantization of non - unitary time evolution in inflating universe. we consider gravitational wave modes in the frw metrics in a de sitter phase and show that the vacuum is a two - mode su ( 1, 1 ) squeezed state of thermo field dynamics, thus exhibiting the link between inflationary evolution and thermal properties. in particular we discuss the entropy and the free energy of the system. the state space splits into many unitarily inequivalent representations of the canonical commutation relations parametrized by time $ t $ and non - unitary time evolution is described as a trajectory in the space of the representations : the system evolves in time by running over unitarily inequivalent representations. the generator of time evolution is related to the entropy operator. a central ingredient in our discussion is the doubling of the degrees of freedom which turns out to be the bridge to the unified picture of non - unitary time evolution, squeezing and thermal properties in inflating metrics. | arxiv:hep-th/9705134 |
the mechanisms controlling the growth rate and composition of epitaxial cdte and cdznte films were studied. the films were grown by isothermal closed space configuration technique. a gaas 100 substrate was exposed sequentially to the elemental sources, zn, te, and cd, in isothermal conditions. while growth of znte followed an atomic layer epitaxy, ale, regime self regulated at one monolayer per cycle ; the cdte films revealed different growth rates in dependence of the growth parameters, exposure and purge times. combination of short purge times and larger cd exposure times led to not self regulated growth regime for cdte. this is ascribed to large cd coverages that were dependent on cd exposure times, following a brunauer - emmett and teller - type adsorption. however, for longer purge times and or short cd exposure times, an ale self regulated regime was achieved with 2 ml per cycle. in this sense, the self - regulation of the growth is limited by desorption, instead of absorption, as in the traditional growth technique. cd atoms substitution by zn atoms and subsequent evaporation of surface cd atoms during zn exposure has been proved. the influence of these facts on the growth and composition of the alloy is discussed. | arxiv:1910.02944 |
we examine the conjecture that an 11d e _ 8 bundle, appearing in the calculation of phases in the m - theory partition function, plays a physical role in m - theory, focusing on consequences for the classification of string theory solitons. this leads for example to a classification of iia solitons in terms of that of le _ 8 bundles in 10d. since k ( z, 2 ) approximates le _ 8 up to \ pi _ { 14 }, this reproduces the k - theoretic classification of iia d - branes while treating nsns and rr solitons more symmetrically and providing a natural interpretation of g _ 0 as the central extension of le _ 8. | arxiv:hep-th/0203218 |
we use exceptional field theory to systematically study all possible consistent truncations around half - maximal ads $ _ 5 $ vacua of m - theory. we show that only truncations with at most three vector multiplets are consistent. the possible gaugings are su ( 2 ) $ \ times $ u ( 1 ) and iso ( 3 ) $ \ times $ u ( 1 ) where, in the first case, the u ( 1 ) factor can have different embeddings inside the global symmetry group so $ ( 5, n ) $, where $ n \ leq 3 $ equals the number of vector multiplets. we show that the iso ( 3 ) $ \ times $ u ( 1 ) truncation only exists around vacua that are locally an $ s ^ 4 $ fibration over a riemann surface, and argue that this is the only consistent truncation with vector multiplets around these vacua that can be constructed by going through the 7 - dimensional so ( 5 ) gauged supergravity obtained after an $ s ^ 4 $ reduction. the consistent truncations with su ( 2 ) $ \ times $ u ( 1 ) gaugings with vector multiplets exist only if certain conditions are satisfied, which we derive. | arxiv:2012.15601 |
in a growth - fragmentation system, cells grow in size slowly and split apart at random. typically, the number of cells in the system grows exponentially and the distribution of the sizes of cells settles into an equilibrium ' asymptotic profile '. in this work we introduce a new method to prove this asymptotic behaviour for the growth - fragmentation equation, and show that the convergence to the asymptotic profile occurs at exponential rate. we do this by identifying an associated sub - markov process and studying its quasi - stationary behaviour via a lyapunov function condition. by doing so, we are able to simplify and generalise results in a number of common cases and offer a unified framework for their study. in the course of this work we are also able to prove the existence and uniqueness of solutions to the growth - fragmentation equation in a wide range of situations. | arxiv:2202.12553 |
the energy and momentum dependence of the gluon self - energy is investigated in a color superconductor with two flavors of massless quarks. the presence of a color - superconducting quark - quark condensate modifies the gluon self - energy for energies which are of the order of the gap parameter. for gluon energies much larger than the gap, the self - energy assumes the form given by the standard hard - dense loop approximation. it is shown that this modification of the gluon self - energy does not affect the magnitude of the gap to leading and subleading order in the weak - coupling limit. | arxiv:nucl-th/0103050 |
in this letter we study the effect of time - reversal symmetric impurities on the josephson supercurrent through two dimensional helical metals such as on topological insulator surface state. we show that contrary to the usual superconducting - normal metal - superconducting junctions, the suppression of supercurrent in superconducting - helical metal - superconducting junction is mainly due to fluctuations of impurities in the junctions. our results, which is a condensed matter realization of a part of the msw effect for neutrinos, shows that the relationship between normal state conductance and critical current of josephson junctions is significantly modified for josephson junctions on the surface of topological insulators. we also study the temperature - dependence of supercurrent and present a two fluid model which can explain some of recent experimental results in josephson junctions on the edge of topological insulators. | arxiv:1506.05103 |
graph neural networks ( gnns ) are known to be vulnerable to oversmoothing due to their implicit homophily assumption. we mitigate this problem with a novel scheme that regulates the aggregation of messages, modulating the type and extent of message passing locally thereby preserving both the low and high - frequency components of information. our approach relies solely on learnt embeddings, obviating the need for auxiliary labels, thus extending the benefits of heterophily - aware embeddings to broader applications, e. g., generative modelling. our experiments, conducted across various data sets and gnn architectures, demonstrate performance enhancements and reveal heterophily patterns across standard classification benchmarks. furthermore, application to molecular generation showcases notable performance improvements on chemoinformatics benchmarks. | arxiv:2504.19785 |
automatic security inspection relying on computer vision technology is a challenging task in real - world scenarios due to many factors, such as intra - class variance, class imbalance, and occlusion. most previous methods rarely touch the cases where the prohibited items are deliberately hidden in messy objects because of the scarcity of large - scale datasets, hindering their applications. to address this issue and facilitate related research, we present a large - scale dataset, named pidray, which covers various cases in real - world scenarios for prohibited item detection, especially for deliberately hidden items. in specific, pidray collects 124, 486 x - ray images for $ 12 $ categories of prohibited items, and each image is manually annotated with careful inspection, which makes it, to our best knowledge, to largest prohibited items detection dataset to date. meanwhile, we propose a general divide - and - conquer pipeline to develop baseline algorithms on pidray. specifically, we adopt the tree - like structure to suppress the influence of the long - tailed issue in the pidray dataset, where the first course - grained node is tasked with the binary classification to alleviate the influence of head category, while the subsequent fine - grained node is dedicated to the specific tasks of the tail categories. based on this simple yet effective scheme, we offer strong task - specific baselines across object detection, instance segmentation, and multi - label classification tasks and verify the generalization ability on common datasets ( e. g., coco and pascal voc ). extensive experiments on pidray demonstrate that the proposed method performs favorably against current state - of - the - art methods, especially for deliberately hidden items. our benchmark and codes will be released at https : / / github. com / lutao2021 / pidray. | arxiv:2211.10763 |
the rapid development in computing technology has paved the way for directive - based programming models towards a principal role in maintaining software portability of performance - critical applications. efforts on such models involve a least engineering cost for enabling computational acceleration on multiple architectures while programmers are only required to add meta information upon sequential code. optimizations for obtaining the best possible efficiency, however, are often challenging. the insertions of directives by the programmer can lead to side - effects that limit the available compiler optimization possible, which could result in performance degradation. this is exacerbated when targeting multi - gpu systems, as pragmas do not automatically adapt to such systems, and require expensive and time consuming code adjustment by programmers. this paper introduces jacc, an openacc runtime framework which enables the dynamic extension of openacc programs by serving as a transparent layer between the program and the compiler. we add a versatile code - translation method for multi - device utilization by which manually - optimized applications can be distributed automatically while keeping original code structure and parallelism. we show in some cases nearly linear scaling on the part of kernel execution with the nvidia v100 gpus. while adaptively using multi - gpus, the resulting performance improvements amortize the latency of gpu - to - gpu communications. | arxiv:2110.14340 |
##tit andrews in reference to alchemy ), the concept of pseudoscience as distinct from real or proper science seems to have become more widespread during the mid - 19th century. among the earliest uses of " pseudo - science " was in an 1844 article in the northern journal of medicine, issue 387 : that opposite kind of innovation which pronounces what has been recognized as a branch of science, to have been a pseudo - science, composed merely of so - called facts, connected together by misapprehensions under the disguise of principles. an earlier use of the term was in 1843 by the french physiologist francois magendie, that refers to phrenology as " a pseudo - science of the present day ". during the 20th century, the word was used pejoratively to describe explanations of phenomena which were claimed to be scientific, but which were not in fact supported by reliable experimental evidence. dismissing the separate issue of intentional fraud – such as the fox sisters ' " rappings " in the 1850s – the pejorative label pseudoscience distinguishes the scientific ' us ', at one extreme, from the pseudo - scientific ' them ', at the other, and asserts that ' our ' beliefs, practices, theories, etc., by contrast with that of ' the others ', are scientific. there are four criteria : ( a ) the ' pseudoscientific ' group asserts that its beliefs, practices, theories, etc., are ' scientific ' ; ( b ) the ' pseudoscientific ' group claims that its allegedly established facts are justified true beliefs ; ( c ) the ' pseudoscientific ' group asserts that its ' established facts ' have been justified by genuine, rigorous, scientific method ; and ( d ) this assertion is false or deceptive : " it is not simply that subsequent evidence overturns established conclusions, but rather that the conclusions were never warranted in the first place " from time to time, however, the usage of the word occurred in a more formal, technical manner in response to a perceived threat to individual and institutional security in a social and cultural setting. = = relationship to science = = pseudoscience is differentiated from science because – although it usually claims to be science – pseudoscience does not adhere to scientific standards, such as the scientific method, falsifiability of claims, and mertonian norms. = = = scientific method = = = a number of basic principles are accepted by scientists as standards for determining whether a body of | https://en.wikipedia.org/wiki/Pseudoscience |
comparable multiplicities and show smooth evolution with multiplicity across all collision systems. although the multiplicity dependence of spectral shapes can be qualitatively described by general - purpose monte carlo ( mc ) event generators, the evolution of yield ratios is barely ( or not ) captured by mc model predictions. | arxiv:1801.03350 |
we use classical or large nc qcd to describe the mesons ( pion, rho, omega ) coming from proton - antiproton annihilation at rest as classical fields, which we then quantize as coherent states. this treatment gives a nearly parameter free account of the pion branching ratios in annihilation. | arxiv:hep-ph/9504362 |
the structural, dielectric, magnetic, and magnetoelectric ( me ) properties of particulate composites containing lead - iron niobate and lead titanate piezoelectric 0. 94 [ pbfe $ _ { 0. 5 } $ nb $ _ { 0. 5 } $ o $ _ 3 $ ] - 0. 06 [ pbti $ _ { 0. 5 } $ o $ _ 3 $ ] ( pfn - pt ) and zn - substituted cobalt ferrite magnetostrictive cofe $ _ { 2 - x } $ zn $ _ { x } $ o $ _ 4 $ ( cf $ _ { 2 - x } $ z $ _ { x } $ o ) ; 0. 6 ( pfn - pt ) / 0. 4 ( cf $ _ { 2 - x } $ z $ _ { x } $ o ), x = 0, 0. 025, 0. 1, 0. 2, 0. 3 ( with ratio of 60 wt \ % ferroelectric and 40 wt \ % ferrite ) ; have been investigated. we investigated the me voltage coefficient as a complex quantity for all composite samples using the dynamic piezomagnetic coefficient, $ q ^ { ac } $ = $ \ partial \ lambda ^ { ac } / { \ partial h } $. the results reveal that tuning the magnetostrictive phase has a strong effect on the real part of the me voltage coefficient. doping zinc into cobalt ferrite modified the magnetic properties of the magnetic phase, such as magnetic anisotropy and coercive field, and hence the me properties. the highest me coefficient value of 12. 33 $ \ frac { mv } { cm. oe } $ was obtained for x = 0. 1 at the magnetic field of 755 oe. in addition, the magnetic field at which the maximum value of the me coefficient was observed ( $ h _ { peak } $ ) strongly depends on the value of zn substitution. the results were interpreted using the magnetic field dependence of the cf $ _ { 2 - x } $ z $ _ { x } $ o magnetostriction. | arxiv:2208.11317 |
higher order topological insulators ( hotis ) are a novel form of insulating quantum matter, which are characterized by having gapped boundaries that are separated by gapless corner or hinge states. recently, it has been proposed that the essential features of a large class of hotis are captured by topological multipolar response theories. in this work, we show that these multipolar responses can be realized in interacting lattice models, which conserve both charge and dipole. in this work we study several models in both the strongly interacting and mean - field limits. in $ 2 $ d we consider a ring - exchange model which exhibits a quadrupole response, and can be tuned to a $ c _ 4 $ symmetric higher order topological phase with half - integer quadrupole moment, as well as half - integer corner charges. we then extend this model to develop an analytic description of adiabatic dipole pumping in an interacting lattice model. the quadrupole moment changes during this pumping process, and if the process is periodic, we show the total change in the quadrupole moment is quantized as an integer. we also consider two interacting $ 3 $ d lattice models with chiral hinge modes. we show that the chiral hinge modes are heralds of a recently proposed " dipolar chern - simons " response, which is related to the quadrupole response by dimensional reduction. interestingly, we find that in the mean field limit, both the $ 2 $ d and $ 3 $ d interacting models we consider here are equivalent to known models of non - interacting hotis ( or boundary obstructed versions ). the self - consistent mean - field theory treatment provides insight into the connection between free - fermion ( mean - field ) theories having vanishing polarization and interacting models where dipole moments are microscopically conserved. | arxiv:2103.00008 |
quantum approximate optimization algorithm ( qaoa ) is a hybrid algorithm whose control parameters are classically optimized. in addition to the variational parameters, the right choice of hyperparameter is crucial for improving the performance of any optimization model. control depth, or the number of variational parameters, is considered as the most important hyperparameter for qaoa. in this paper we investigate the control depth selection with an automatic algorithm based on proximal gradient descent. the performances of the automatic algorithm are demonstrated on 7 - node and 10 - node max - cut problems, which show that the control depth can be significantly reduced during the iteration while achieving an sufficient level of optimization accuracy. with theoretical convergence guarantee, the proposed algorithm can be used as an efficient tool for choosing the appropriate control depth as a replacement of random search or empirical rules. moreover, the reduction of control depth will induce a significant reduction in the number of quantum gates in circuit, which improves the applicability of qaoa on noisy intermediate - scale quantum ( nisq ) devices. | arxiv:2206.14412 |
recently, several people study finite multiple zeta values ( fmzvs ) and finite polylogarithms ( fps ). in this paper, we introduce finite multiple polylogarithms ( fmps ), which are natural generalizations of fmzvs and fps, and we establish functional equations of fmps. as applications of these functional equations, we calculate special values of fmps containing generalizations of congruences obtained by me \ v { s } trovi \ ' c, z. w. sun, z. w. sun - l. l. zhao, and tauraso - j. zhao. we show supercongruences for certain generalized bernoulli numbers and the bernoulli numbers as an appendix. | arxiv:1509.07653 |
we introduce a non - perturbative method to constrain the amplitude of local - type primordial non - gaussianity ( $ f _ { \ rm nl } $ ) using squeezed configurations of the cmb lensing convergence and cosmic shear bispectra. first, we use cosmological consistency relations to derive a model for the squeezed limit of angular auto - and cross - bispectra of lensing convergence fields in the presence of $ f _ { \ rm nl } $. using this model, we perform a fisher forecast with specifications expected for upcoming cmb lensing measurements from the simons observatory and cmb - s4, as well as cosmic shear measurements from a rubin lsst / euclid - like experiment. assuming a minimum multipole $ \ ell _ { \ rm min } = 10 $ and maximum multipole $ \ ell _ { \ rm max } = 1400 $, we forecast $ \ sigma _ { f _ { \ rm nl } } = 175 $ ( $ 95 $ ) for simons observatory ( cmb - s4 ). our forecasts improve considerably for an lsst / euclid - like cosmic shear experiment with three tomographic bins and $ \ ell _ { \ rm min } = 10 $ and $ \ ell _ { \ rm max } = 1400 $ ( $ 5000 $ ) with $ \ sigma _ { f _ { \ rm nl } } = 31 $ ( $ 16 $ ). a joint analysis of cmb - s4 lensing and lsst / euclid - like shear yields little gain over the shear - only forecasts ; however, we show that a joint analysis could be useful if the cmb lensing convergence can be reliably reconstructed at larger angular scales than the shear field. the method presented in this work is a novel and robust technique to constrain local primordial non - gaussianity from upcoming large - scale structure surveys that is completely independent of the galaxy field ( and therefore any nuisance parameters such as $ b _ \ phi $ ), thus complementing existing techniques to constrain $ f _ { \ rm nl } $ using the scale - dependent halo bias. | arxiv:2310.12959 |
semileptonic decays of heavy baryons consisting of one heavy ( q = b, c ) and two light ( q = u, d, s ) quarks are considered in the heavy - quark - - light - diquark approximation. the relativistic quasipotential equation is used for obtaining masses and wave functions of both diquarks and baryons within the constituent quark model. the weak transition matrix elements are expressed through the overlap integrals of the baryon wave functions. the isgur - wise functions are determined in the whole accessible kinematic range. the exclusive semileptonic decay rates are calculated with applying the heavy quark 1 / m _ q expansion. the evaluated lambda _ b - > lambda _ c l nu decay rate agrees with its experimental value. | arxiv:hep-ph/0610238 |
high - dimensional data classification is a fundamental task in machine learning and imaging science. in this paper, we propose a two - stage multiphase semi - supervised classification method for classifying high - dimensional data and unstructured point clouds. to begin with, a fuzzy classification method such as the standard support vector machine is used to generate a warm initialization. we then apply a two - stage approach named sat ( smoothing and thresholding ) to improve the classification. in the first stage, an unconstraint convex variational model is implemented to purify and smooth the initialization, followed by the second stage which is to project the smoothed partition obtained at stage one to a binary partition. these two stages can be repeated, with the latest result as a new initialization, to keep improving the classification quality. we show that the convex model of the smoothing stage has a unique solution and can be solved by a specifically designed primal - dual algorithm whose convergence is guaranteed. we test our method and compare it with the state - of - the - art methods on several benchmark data sets. the experimental results demonstrate clearly that our method is superior in both the classification accuracy and computation speed for high - dimensional data and point clouds. | arxiv:1905.08538 |
it has long been a standard practice to neglect diffusive effects in stability analyses of detonation waves. here, with the principal aim of quantifying the impact of these oft - neglected effects on the stability characteristics of such waves, we use numerical evans - function techniques to study the ( spectral ) stability of viscous strong detonation waves - - - particular traveling - wave solutions of the navier - stokes equations modeling a mixture of reacting gases. remarkably, our results show a surprising synergy between the high - activation - energy limit typically studied in stability analyses of detonation waves and the presence of small but nonzero diffusive effects. while our calculations do show a modest delay in the onset of instability in agreement with recently reported calculations by direct numerical simulation of the physical equations, our approach, based on the evans function, also provides additional spectral information. in particular, for each of the families of detonation waves in our computational domain, we find a completely unexpected kind of hysteresis in the limit of increasing activation energy ; that is, our calculations suggest that, whenever diffusive effects are present, there is a return to stability as unstable eigenvalues return to the stable complex half plane. | arxiv:1311.6417 |
we review some connections between quantum information and statistical mechanics. we focus on three sets of results for classical spin models. first, we show that the partition function of all classical spin models ( including models in different dimensions, different types of many - body interactions, different symmetries, etc ) can be mapped to the partition function of a single model. second, we give efficient quantum algorithms to estimate the partition function of various classical spin models, such as the ising or the potts model. the proofs of these two results are based on a mapping from partition functions to quantum states and to quantum circuits, respectively. finally, we show how classical spin models can be used to describe certain fluctuating lattices appearing in models of discrete quantum gravity. | arxiv:1312.6007 |
we investigate aspects of low - magnetic - reynolds - number flow between two parallel, perfectly insulating walls, in the presence of an imposed magnetic field parallel to the bounding walls. we find a functional basis to describe the flow, well adapted to the problem of finding the attractor dimension, and which is also used in subsequent direct numerical simulation of these flows. for given reynolds and hartmann numbers, we obtain an upper bound for the dimension of the attractor by means of known bounds on the nonlinear inertial term and this functional basis for the flow. three distinct flow regimes emerge : a quasi - isotropic 3d flow, a non - isotropic three - dimensional ( 3d ) flow, and a 2d flow. we find the transition curves between these regimes in the space parameterized by hartmann number ha and attractor dimension $ d _ \ text { att } $. we find how the attractor dimension scales as a function of reynolds and hartmann numbers ( re and ha ) in each regime. we also investigate the thickness of the boundary layer along the bounding wall, and find that in all regimes this scales as 1 / re, independently of the value of ha, unlike hartmann boundary layers found when the field is normal to the channel. the structure of the set of least dissipative modes is indeed quite different between these two cases but the properties of turbulence far from the walls ( smallest scales and number of degrees of freedom ) are found to be very similar. | arxiv:1410.0637 |
video quality assessment is a challenging problem having a critical significance in the context of medical imaging. for instance, in laparoscopic surgery, the acquired video data suffers from different kinds of distortion that not only hinder surgery performance but also affect the execution of subsequent tasks in surgical navigation and robotic surgeries. for this reason, we propose in this paper neural network - based approaches for distortion classification as well as quality prediction. more precisely, a residual network ( resnet ) based approach is firstly developed for simultaneous ranking and classification task. then, this architecture is extended to make it appropriate for the quality prediction task by using an additional fully connected neural network ( fcnn ). to train the overall architecture ( resnet and fcnn models ), transfer learning and end - to - end learning approaches are investigated. experimental results, carried out on a new laparoscopic video quality database, have shown the efficiency of the proposed methods compared to recent conventional and deep learning based approaches. | arxiv:2202.04517 |
in this paper we systematically describe relations between various structure sets which arise naturally for pairs of compact topological manifolds with boundary. our consideration is based on a deep analogy between the case of a compact manifold with boundary and the case of a closed manifold pair. this approach also gives a possibility to construct the obstruction groups for natural maps of various structure sets and to investigate their properties. | arxiv:0908.1372 |
we study the topology of exact and stein fillings of the canonical contact structure on the unit cotangent bundle of a closed surface $ \ sigma _ g $, where $ g $ is at least 2. in particular, we prove a uniqueness theorem asserting that any stein filling must be s - cobordant rel boundary to the disk cotangent bundle of $ \ sigma _ g $. for exact fillings, we show that the rational homology agrees with that of the disk cotangent bundle, and that the integral homology takes on finitely many possible values : for example, if $ g - 1 $ is square - free, then any exact filling has the same integral homology and intersection form as $ dt ^ * \ sigma _ g $. | arxiv:1510.06736 |
we present a numerical study of riemann ' s formula for the oscillating part of the density of the primes and their powers. the formula is comprised of an infinite series of oscillatory terms, one for each zero of the zeta function on the critical line and was derived by riemann in his paper on primes assuming the riemann hypothesis. we show that high resolution spectral lines can be generated by the truncated series at all powers of primes and demonstrate explicitly that the relative line intensities are correct. we then derive a gaussian sum rule for riemann ' s formula. this is used to analyze the numerical convergence of the truncated series. the connections to quantum chaos and semiclassical physics are discussed. | arxiv:nlin/0212042 |
in charmed $ d $ and $ d _ s $ mesons sector, the matrix of a hamiltonian in a quark potential model is computed in the $ 2 ^ 3s _ 1 $ and $ 1 ^ 3d _ 1 $ subspace. the masses of four mixed states of $ 2 ^ 3s _ 1 $ and $ 1 ^ 3d _ 1 $ denoted with $ d ^ * _ 1 ( 2635 ) $, $ d ^ * _ 1 ( 2739 ) $, $ d ^ * _ { s1 } ( 2715 ) $ and $ d ^ * _ { s1 } ( 2805 ) $ are obtained. it is an off - diagonal part of the spin - orbit tensor interaction that causes the mixing between the $ 2 ^ 3s _ 1 $ and $ 1 ^ 3d _ 1 $ states. the mixing angles between the $ 2 ^ 3s _ 1 $ and $ 1 ^ 3d _ 1 $ states are tiny. under the mixing, a $ ^ 3p _ 0 $ model is employed to compute the hadronic decay widths of all ozi - allowed decay channels of the four mixed states. the two light mixed states $ d ^ * _ 1 ( 2635 ) $ and $ d ^ * _ { s1 } ( 2715 ) $ are close in mass to $ d ^ * _ j ( 2600 ) $ and $ d ^ * _ { s1 } ( 2700 ) $, while the two heavy mixed states $ d ^ * _ 1 ( 2739 ) $ and $ d ^ * _ { s1 } ( 2805 ) $ are lighter in mass than $ d ( 2750 ) $ and $ d ^ * _ { s1 } ( 2860 ) $. the mixing angles obtained from dynamical interaction are inconsistent with the mixing angles obtained from hadronic decay. based on mass spectra and hadronic decay analyses, $ d ^ * _ j ( 2600 ) $, $ d ( 2750 ) $, $ d ^ * _ { s1 } ( 2700 ) $ and $ d ^ * _ { s1 } ( 2860 ) $ are impossibly the mixed states of $ 2 ^ 3s _ 1 $ and $ 1 ^ 3d _ 1 $ at the small mixing angles. the inconsistence implies that $ d ^ * _ 1 ( 2760 ) $ and $ d ^ * _ { s1 } ( 2860 ) $ have not been properly resolved from present experimental data, or there | arxiv:2006.01347 |
. | arxiv:2309.15986 |
we consider an extension of the standard model based on the group $ \ mathrm { u } ( 2 ) \ times \ mathrm { u } ( 3 ) $, which is naturally compatible with the standard model interacting - particle representations and the spontaneous symmetry breaking of $ \ mathrm { u } ( 2 ) \ times \ mathrm { u } ( 3 ) $ to an electrostrong $ \ mathrm { u } ( 3 ) $. in its minimal version, the model only adds one extra $ \ mathrm { u } ( 1 ) $ gauge boson and it implies that the hypercharge is distributed between the factors of the hyperweak and hyperstrong forces. we show that the anomaly cancellation condition can be solved by adding exotic fermions associated with a $ 16 $ - dimensional representation of $ \ mathrm { u } ( 2 ) \ times \ mathrm { u } ( 3 ) $. a brief discussion of the mechanism of the spontaneous breakdown of $ \ mathrm { u } ( 2 ) \ times \ mathrm { u } ( 3 ) $ in the gauge boson sector is given. | arxiv:1707.09367 |
we report the b band optical observations of an old ( 17. 5 myr ) radiopulsar psr b0950 + 08 obtained with the suprime - cam at the subaru telescope. we detected a faint object, b = 27. 07 ( 16 ). within our astrometrical accuracy it coincides with the radio position of the pulsar and with the object detected earlier by pavlov et al. ( 1996 ) in uv with the hst / foc / f130lp. the positional coincidence and spectral properties of the object suggest that it is the optical counterpart of psr b0950 + 08. its flux in the b band is two times higher than one would expect from the suggested earlier rayleigh - jeans interpretation of the only available hst observations in the adjacent f130lp band. based on the b and f130lp photometry of the suggested counterpart and on the available x - ray data we argue in favour of nonthermal origin of the broad - band optical spectrum of psr b0950 + 08, as it is observed for the optical emission of the younger, middle - aged pulsars psr b0656 + 14 and geminga. at the same time, the optical efficiency of psr b0950 + 08, estimated from its spin - down power and the detected optical flux, is by several orders of magnitude higher than for these pulsars, and comparable with that for the much younger and more energetic crab pulsar. we cannot exclude the presence of a compact, about 1 ' ', faint pulsar nebula around psr b0950 + 08, elongated perpendicular to the vector of its proper motion, unless it is not a projection of a faint extended object on the pulsar position. | arxiv:astro-ph/0206229 |
in this paper, we consider the littlewood - offord problems in one dimension for the curie - weiss models. let \ [ q _ n ^ { + } : = \ sup _ { x \ in \ mathbb { r } } \ sup _ { v _ 1, v _ 2, \ ldots, v _ n \ geq 1 } p ( \ sum _ { i = 1 } ^ { n } v _ i \ varepsilon _ i \ in ( x - 1, x + 1 ) ), \ ] \ [ q _ n = \ sup _ { x \ in \ mathbb { r } } \ sup _ { | v _ 1 |, | v _ 2 |, \ ldots, | v _ n | \ geq 1 } p ( \ sum _ { i = 1 } ^ { n } v _ i \ varepsilon _ i \ in ( x - 1, x + 1 ) ) \ ] where the random variables $ ( \ varepsilon _ i ) _ { 1 \ leq i \ leq n } $ are spins in curie - weiss models. we calculate the asymptotic properties of $ q _ n ^ { + } $ and $ q _ n $ as $ n \ to \ infty $ and observe the phenomena of phase transitions. meanwhile, we also get that $ q _ n ^ { + } $ is attained when $ v _ 1 = v _ 2 = \ cdots = v _ n = 1 $. and $ q _ n $ is attained when one half of $ ( v _ i ) _ { 1 \ leq i \ leq n } $ equals to $ 1 $ and the other half equals to $ - 1 $ when $ n $ is even. this is a generalization of classical littlewood - offord problems from rademacher random variables to possibly dependent random variables. in particular, it includes the case of general independent and identically distributed bernoulli random variables. | arxiv:2408.00127 |
breitenberger ' s uncertainty principle on the torus $ \ mathbb { t } $ and its higher - dimensional analogue on $ \ mathbb { s } ^ { d - 1 } $ are well understood. we give describe an entire family of uncertainty principles on compact manifolds $ ( m, g ) $, which includes the classical heisenberg - weyl uncertainty principle ( for $ m = b ( 0, 1 ) \ subset \ mathbb { r } ^ d $ the unit ball with the flat metric ) and the goh - goodman uncertainty principle ( for $ m = \ mathbb { s } ^ { d - 1 } $ with the canonical metric ) as special cases. this raises a new geometric problem related to small - curvature low - distortion embeddings : given a function $ f : m \ rightarrow \ mathbb { r } $, which uncertainty principle in our family yields the best result? we give a ( far from optimal ) answer for the torus, discuss disconnected manifolds and state a variety of other open problems. | arxiv:1411.1383 |
recently, there has been a growing interest among large language model ( llm ) developers in llm - based document reading systems, which enable users to upload their own documents and pose questions related to the document contents, going beyond simple reading comprehension tasks. consequently, these systems have been carefully designed to tackle challenges such as file parsing, metadata extraction, multi - modal information understanding and long - context reading. however, no current benchmark exists to evaluate their performance in such scenarios, where a raw file and questions are provided as input, and a corresponding response is expected as output. in this paper, we introduce docbench, a new benchmark designed to evaluate llm - based document reading systems. our benchmark involves a meticulously crafted process, including the recruitment of human annotators and the generation of synthetic questions. it includes 229 real documents and 1, 102 questions, spanning across five different domains and four major types of questions. we evaluate both proprietary llm - based systems accessible via web interfaces or apis, and a parse - then - read pipeline employing open - source llms. our evaluations reveal noticeable gaps between existing llm - based document reading systems and human performance, underscoring the challenges of developing proficient systems. to summarize, docbench aims to establish a standardized benchmark for evaluating llm - based document reading systems under diverse real - world scenarios, thereby guiding future advancements in this research area. | arxiv:2407.10701 |
typical structure - from - motion ( sfm ) pipelines rely on finding correspondences across images, recovering the projective structure of the observed scene and upgrading it to a metric frame using camera self - calibration constraints. solving each problem is mainly carried out independently from the others. for instance, camera self - calibration generally assumes correct matches and a good projective reconstruction have been obtained. in this paper, we propose a unified sfm method, in which the matching process is supported by self - calibration constraints. we use the idea that good matches should yield a valid calibration. in this process, we make use of the dual image of absolute quadric projection equations within a multiview correspondence framework, in order to obtain robust matching from a set of putative correspondences. the matching process classifies points as inliers or outliers, which is learned in an unsupervised manner using a deep neural network. together with theoretical reasoning why the self - calibration constraints are necessary, we show experimental results demonstrating robust multiview matching and accurate camera calibration by exploiting these constraints. | arxiv:2007.02045 |
the potentials and string tensions between static sources in a variety of representations ( fundamental, 8, 6, 15 - antisymmetric, 10, 27 and 15 - symmetric ) have been computed by measuring wilson loops in pure gauge su ( 3 ). the simulations have been done primarily on anisotropic lattices, using a tadpole improved action improved to o ( a _ { s } ^ 4 ). a range of lattice spacings ( 0. 43 fm, 0. 25 fm and 0. 11 fm ) and volumes ( $ 8 ^ 3 \ times 24 $, $ 10 ^ 3 \ times 24 $, $ 16 ^ 3 \ times 24 $ and $ 18 ^ 3 \ times 24 $ ) has been used in an attempt to control discretization and finite volume effects. at intermediate distances, the results show approximate casimir scaling. finite lattice spacing effects dominate systematic error, and are particularly large for the representations with the largest string tensions. | arxiv:hep-lat/9911008 |
we discuss an universal relation $ \ epsilon ( i \ kappa ) = 0 $ with $ { \ rm re } \ kappa = 1 / \ xi $ in 1d quantum spin systems with an excitation gap, where $ \ epsilon ( k ) $ is the dispersion curve of the low - energy excitation and $ \ xi $ is the correlation length of the ground - state. we first discuss this relation for integrable models such as the ising model in a transverse filed and the xyz model. we secondly make a derivation of the relation for general cases, in connection with the equilibrium crystal shape in the corresponding 2d classical system. we finally verify the relation for the s = 1 bilinear - biquadratic spin chain and $ s = 1 / 2 $ zigzag spin ladder numerically. | arxiv:cond-mat/0107021 |
let $ m $ be a $ 2m $ - dimensional compact riemannian manifold. we show that the spectrum of the hodge laplacian acting on $ m $ - forms does not determine whether the manifold has boundary, nor does it determine the lengths of the closed geodesics. among the many examples are a projective space and a hemisphere that have the same hodge spectrum on 1 - forms, and hyperbolic surfaces, mutually isospectral on 1 - forms, with different injectivity radii. the hodge $ m $ - spectrum also does not distinguish orbifolds from manifolds. | arxiv:math/0111016 |
of relevance to energy storage, electrochemistry and catalysis, ionic and dipolar liquids display unexpected behaviours - especially in confinement. beyond adsorption, over - screening and crowding effects, experiments have highlighted novel phenomena, such as unconventional screening and the impact of the electronic nature - metallic versus insulating - of the confining surface. such behaviours, which challenge existing frameworks, highlight the need for tools to fully embrace the properties of confined liquids. here we introduce a novel approach that involves electronic screening while capturing molecular aspects of interfacial fluids. although available strategies consider perfect metal or insulator surfaces, we build on the thomas - fermi formalism to develop an effective approach that deals with any imperfect metal between these asymptotes. our approach describes electrostatic interactions within the metal through a ' virtual ' thomas - fermi fluid of charged particles, whose debye length sets the screening length $ \ lambda $. we show that this method captures the electrostatic interaction decay and electrochemical behaviour on varying $ \ lambda $. by applying this strategy to an ionic liquid, we unveil a wetting transition on switching from insulating to metallic conditions. | arxiv:2002.11526 |
the success of the quantum level predictions of the standard model on the $ z $ boson properties, on $ \ mw $ and on $ \ mt $, which makes use of the muon lifetime as an input, implies a stringent constraint on new physics contributions to the $ v - a $ charged - current interactions among leptons. observed unitarity of the ckm matrix elements then implies constraints on non - standard contributions to the lepton - quark charged - current interactions. by using the recent electroweak data as inputs, we find the 95 % ~ cl limits for the corresponding contact interactions : $ \ lambda _ { cc, + } ^ { \ ell \ ell } > 7. 5 $ tev and $ \ lambda _ { cc, - } ^ { \ ell \ ell } > 10. 2 $ tev for the purely leptonic terms, and $ \ lambda _ { cc, + } ^ { \ ell q } > 5. 8 $ tev and $ \ lambda _ { cc, - } ^ { \ ell q } > 10. 1 $ ~ tev for the lepton - quark contact interactions. | arxiv:hep-ph/9712260 |
road corrugation refers to the formation of periodic, transverse ripples on unpaved road surfaces. it forms spontaneously on an initially flat surface under heavy traffic and can be considered to be a type of unstable growth phenomenon, possibly caused by the local volume contraction of the underlying soil due to a moving vehicle ' s weight. in the present work, we demonstrate a possible mechanism for road corrugation using experimental data of soil consolidation and numerical simulations. the results indicate that the vertical oscillation of moving vehicles, which is excited by the initial irregularities of the surface, plays a key role in the development of corrugation. | arxiv:2007.05109 |
population iii stars, the first generation of stars formed from primordial big bang material with a top - heavy imf, should contribute substantially to the universe reionization and they are crucial for understanding the early metal enrichment of galaxies. therefore it is very important that these objects, foreseen by theories, are detected by observations. however popiii stars, searched through the heii 1640a line signature, have remained elusive. we report about the search for the heii line in a galaxy at z = 6. 5, which is a very promising candidate. unfortunately we are not yet able to show the results of this search. however we call attention to the possible detection of popiii stars in a lensed hii dwarf galaxy at z = 3. 4, which appeared in the literature some years ago, but has been overlooked. | arxiv:0807.4634 |
for light fields, the coherence in longitudinal direction is governed by both the frequency spectra and angular spectra they possess. in this work, we develop and report a theoretical formulation to demonstrate the effect of the angular spectra of electromagnetic light fields in quantifying their longitudinal spatial coherence. the experimental results obtained by measuring the electromagnetic longitudinal spatial coherence and degree of cross - polarization of uniformly polarized light fields for different angular spectra validate the theoretical findings. | arxiv:1907.05831 |
the multi - branched husimi recursive lattice has been extended to a virtual structure with fractional numbers of branches joined on one site. although the lattice is undrawable in real space, the concept is consistent with regular husimi lattice. the ising spins of antiferromagnetic interaction on such a sets of lattices were calculated to check the critical temperatures ( $ t _ { c } $ ) and ideal glass transition temperatures ( $ t _ { k } $ ) variation with fractional branch numbers. besides the similar results of two solutions representing the stable state ( crystal ) and metastable state ( supercooled liquid ) and indicating the phase transition temperatures, the phase transitions show a well - defined shift with branch number variation. therefore the fractional branch number as a parameter can be used as an adjusting tool in constructing a recursive lattice model to describe real systems. | arxiv:1405.7620 |
suppose that there is a quantum operator that describes the horizon area of a black hole. then what would be the form of the ensuing quantum spectrum? in this regard, it has been conjectured that the characteristic frequencies of the black hole oscillations can be used to calibrate the spacing between the spectral levels. the current article begins with a brief review of this conjecture and some of its subsequent developments. we then suggest a simple but vital modification to a recent treatment on the kerr ( or rotating black hole ) spectrum. as a consequence of this refinement, we are able to rectify a prior inconsistency ( as was found between two distinct calculations ) and to establish, unambiguously, a universal form for the kerr and schwarzschild spectra. | arxiv:0804.4346 |
regressing the vector field of a dynamical system from a finite number of observed states is a natural way to learn surrogate models for such systems. we present variants of cross - validation ( kernel flows \ cite { owhadi19 } and its variants based on maximum mean discrepancy and lyapunov exponents ) as simple approaches for learning the kernel used in these emulators. | arxiv:2007.05074 |
in this paper, we will study the emergent dynamics of the discrete kuramoto model for generic initial data. this is an extension of the previous work s. - y. ha et al. ( 2019 ), in which the initial configurations are supposed to be within a half circle. more precisely, we will provide the theory of discrete gradient flow which can be applied to general euler iteration scheme. therefore, as a direct application, we conclude the emergence of synchronization of discrete kuramoto model. moreover, we obtain for small mesh size that, the synchronization will occur exponentially fast for initial data in a _ 1 ( see definition in ( 4. 1 ) ). | arxiv:1909.03358 |
point - cloud - based 3d object detection suffers from performance degradation when encountering data with novel domain gaps. to tackle it, the single - domain generalization ( sdg ) aims to generalize the detection model trained in a limited single source domain to perform robustly on unexplored domains. in this paper, we propose an sdg method to improve the generalizability of 3d object detection to unseen target domains. unlike prior sdg works for 3d object detection solely focusing on data augmentation, our work introduces a novel data augmentation method and contributes a new multi - task learning strategy in the methodology. specifically, from the perspective of data augmentation, we design a universal physical - aware density - based data augmentation ( pdda ) method to mitigate the performance loss stemming from diverse point densities. from the learning methodology viewpoint, we develop a multi - task learning for 3d object detection : during source training, besides the main standard detection task, we leverage an auxiliary self - supervised 3d scene restoration task to enhance the comprehension of the encoder on background and foreground details for better recognition and detection of objects. furthermore, based on the auxiliary self - supervised task, we propose the first test - time adaptation method for domain generalization of 3d object detection, which efficiently adjusts the encoder ' s parameters to adapt to unseen target domains during testing time, to further bridge domain gaps. extensive cross - dataset experiments covering " car ", " pedestrian ", and " cyclist " detections, demonstrate our method outperforms state - of - the - art sdg methods and even overpass unsupervised domain adaptation methods under some circumstances. | arxiv:2311.10845 |
bibliometric - enhanced information retrieval ( bir ) workshops serve as the annual gathering of ir researchers who address various information - related tasks on scientific corpora and bibliometrics. the workshop features original approaches to search, browse, and discover value - added knowledge from scientific documents and related information networks ( e. g., terms, authors, institutions, references ). we welcome contributions elaborating on dedicated ir systems, as well as studies revealing original characteristics on how scientific knowledge is created, communicated, and used. in this paper we introduce the bir workshop series and discuss some selected papers presented at previous bir workshops. | arxiv:1710.11231 |
electromagnetic soliton - particle with both quasi - static and quick - oscillating wave parts is considered. its mass, spin, charge, and magnetic moment appear naturally when the interaction with distant solitons is considered. the substantiation of dirac equation for the wave part of the interacting soliton - particle is given. | arxiv:1212.4468 |
in this paper, we initiate a principled study of how the generalization properties of approximate differential privacy can be used to perform adaptive hypothesis testing, while giving statistically valid $ p $ - value corrections. we do this by observing that the guarantees of algorithms with bounded approximate max - information are sufficient to correct the $ p $ - values of adaptively chosen hypotheses, and then by proving that algorithms that satisfy $ ( \ epsilon, \ delta ) $ - differential privacy have bounded approximate max information when their inputs are drawn from a product distribution. this substantially extends the known connection between differential privacy and max - information, which previously was only known to hold for ( pure ) $ ( \ epsilon, 0 ) $ - differential privacy. it also extends our understanding of max - information as a partially unifying measure controlling the generalization properties of adaptive data analyses. we also show a lower bound, proving that ( despite the strong composition properties of max - information ), when data is drawn from a product distribution, $ ( \ epsilon, \ delta ) $ - differentially private algorithms can come first in a composition with other algorithms satisfying max - information bounds, but not necessarily second if the composition is required to itself satisfy a nontrivial max - information bound. this, in particular, implies that the connection between $ ( \ epsilon, \ delta ) $ - differential privacy and max - information holds only for inputs drawn from product distributions, unlike the connection between $ ( \ epsilon, 0 ) $ - differential privacy and max - information. | arxiv:1604.03924 |
convolutional neural networks ( cnns ) are able to attain better visual recognition performance than fully connected neural networks despite having much fewer parameters due to their parameter sharing principle. modern architectures usually contain a small number of fully - connected layers, often at the end, after multiple layers of convolutions. in some cases, most of the convolutions can be eliminated without suffering any loss in recognition performance. however, there is no solid recipe to detect the hidden subset of convolutional neurons that is responsible for the majority of the recognition work. in this work, we formulate this as a pruning problem where the aim is to prune as many kernels as possible while preserving the vanilla generalization performance. to this end, we use the matrix characteristics based on eigenvalues for pruning, in comparison to the average absolute weight of a kernel which is the de facto standard in the literature to assess the importance of an individual convolutional kernel, to shed light on the internal mechanisms of a widely used family of cnns, namely residual neural networks ( resnets ), for the image classification problem using cifar - 10, cifar - 100 and tiny imagenet datasets. | arxiv:2102.02804 |
we study a branching random walk on $ \ r $ with an absorbing barrier. the position of the barrier depends on the generation. in each generation, only the individuals born below the barrier survive and reproduce. given a reproduction law, biggins et al. \ cite { blsw91 } determined whether a linear barrier allows the process to survive. in this paper, we refine their result : in the boundary case in which the speed of the barrier matches the speed of the minimal position of a particle in a given generation, we add a second order term $ a n ^ { 1 / 3 } $ to the position of the barrier for the $ n ^ \ mathrm { th } $ generation and find an explicit critical value $ a _ c $ such that the process dies when $ aa _ c $. we also obtain the rate of extinction when $ a < a _ c $ and a lower bound on the surviving population when $ a > a _ c $. | arxiv:0911.2227 |
the xbootes survey is a 5 - ks chandra survey of the bootes field of the noao deep wide - field survey ( ndwfs ). this survey is unique in that it is the largest ( 9. 3 deg ^ 2 ), contiguous region imaged in x - ray with complementary deep optical and near - ir observations. we present a catalog of the optical counterparts to the 3, 213 x - ray point sources detected in the xbootes survey. using a bayesian identification scheme, we successfully identified optical counterparts for 98 % of the x - ray point sources. the optical colors suggest that the optically detected galaxies are a combination of z < 1 massive early - type galaxies and bluer star - forming galaxies whose optical agn emission is faint or obscured, whereas the majority of the optically detected point sources are likely quasars over a large redshift range. our large area, x - ray bright, optically deep survey enables us to select a large sub - sample of sources ( 773 ) with high x - ray to optical flux ratios ( f _ x / f _ o > 10 ). these objects are likely high redshift and / or dust obscured agn. these sources have generally harder x - ray spectra than sources with 0. 1 < f _ x / f _ o < 10. of the 73 x - ray sources with no optical counterpart in the ndwfs catalog, 47 are truly optically blank down to r ~ 25. 5 ( the average 50 % completeness limit of the ndwfs r - band catalogs ). these sources are also likely to be high redshift and / or dust obscured agn. | arxiv:astro-ph/0512343 |
we study egalmab, an egalitarian assignment problem in the context of stochastic multi - armed bandits. in egalmab, an agent is tasked with assigning a set of users to arms. at each time step, the agent must assign exactly one arm to each user such that no two users are assigned to the same arm. subsequently, each user obtains a reward drawn from the unknown reward distribution associated with its assigned arm. the agent ' s objective is to maximize the minimum expected cumulative reward among all users over a fixed horizon. this problem has applications in areas such as fairness in job and resource allocations, among others. we design and analyze a ucb - based policy egalucb and establish upper bounds on the cumulative regret. in complement, we establish an almost - matching policy - independent impossibility result. | arxiv:2410.05856 |
in this paper we construct the classical phase space of jackiw - teitelboim gravity with positive cosmological constant on spatial slices with circle topology. this turns out to be somewhat more intricate than in the case of negative cosmological constant ; this phase space has many singular points and is not even hausdorff. nonetheless, it admits a group - theoretic description which is quite amenable to quantization. | arxiv:2409.12943 |
runaway electrons ( res ) present a high - priority issue for iter but little is known about the extent to which re generation is affected by the stochastic field intrinsic to disrupting plasmas. re generation can be modelled with reduced kinetic models and there has been recent progress in involving losses due to field stochasticity, either via a loss - time parameter or radial transport coefficients which can be estimated by tracing test electrons in 3d fields. we evaluate these terms in iter using a recent jorek 3d mhd simulation of plasma disruption to provide the stochastic magnetic fields where re markers are traced with the built - in particle tracing module. while the mhd simulation modelled only the current quench phase, the case is mhd unstable and exhibits similar relaxation as would be expected during the thermal quench. therefore, the re simulations can be considered beginning right after the thermal quench but before the mhd relaxation is complete. the plasma is found to become fully stochastic for 8 ms and the resulting transport is sufficient to overcome re avalanche before flux surfaces are reformed. we also study transport mechanisms for trapped res and find those to be deconfined as well during this phase. while the results presented here are not sufficient to assess the magnitude of the formed re beam, we show that significant re losses could be expected to arise due to field stochasticity. | arxiv:2203.09344 |
the tolman - bondi and vaidya solutions are two solutions to einstein equations which describe dust particles and null fluid, respectively. we show that it is possible to match the two solutions in one single spacetime, the tolman - bondi - - vaidya spacetime. the new spacetime is divided by a null surface with tolman - bondi dust on one side and vaidya fluid on the other side. the differentiability of the spacetime is discussed. by constructing a specific solution, we show that the metric across the null surface can be at least $ c ^ 1 $ and the stress - energy tensor is continuous. | arxiv:gr-qc/0504045 |
we investigate the formation and early evolution of star clusters assuming that they form from a turbulent starless clump of given mass bounded inside a parent self - gravitating molecular cloud characterized by a particular mass surface density. as a first step we assume instantaneous star cluster formation and gas expulsion. we draw our initial conditions from observed properties of starless clumps. we follow the early evolution of the clusters up to 20 myr, investigating effects of different star formation efficiencies, primordial binary fractions and eccentricities and primordial mass segregation levels. we investigate clumps with initial masses of $ m _ { \ rm cl } = 3000 \ : { \ rm m } _ \ odot $ embedded in ambient cloud environments with mass surface densities, $ \ sigma _ { \ rm cloud } = 0. 1 $ and $ 1 \ : { \ rm g \ : cm ^ { - 2 } } $. we show that these models of fast star cluster formation result, in the fiducial case, in clusters that expand rapidly, even considering only the bound members. clusters formed from higher $ \ sigma _ { \ rm cloud } $ environments tend to expand more quickly, so are soon larger than clusters born from lower $ \ sigma _ { \ rm cloud } $ conditions. to form a young cluster of a given age, stellar mass and mass surface density, these models need to assume a parent molecular clump that is many times denser, which is unrealistic compared to observed systems. we also show that in these models the initial binary properties are only slightly modified by interactions, meaning that binary properties, e. g., at 20 myr, are very similar to those at birth. with this study we set up the basis of future work where we will investigate more realistic models of star formation compared to this instantaneous, baseline case. | arxiv:1701.00701 |
a new heavy resonance may be observable at the lhc if it has a significant decay branching fraction into a pair of photons. we entertain this possibility by looking at the modest excess in the diphoton invariant mass spectrum around 750 gev recently reported in the atlas and cms experiments. assuming that it is a spinless boson, dubbed $ \ tilde s $, we consider it within a model containing two weak scalar doublets having zero vacuum expectation values and a scalar singlet in addition to the doublet responsible for breaking the electroweak symmetry. the model also possesses three dirac neutral singlet fermions, the lightest one of which can play the role of dark matter and which participate with the new doublet scalars in generating light neutrino masses radiatively. we show that the model is consistent with all phenomenological constraints and can yield a production cross section $ \ sigma ( pp \ rightarrow \ tilde { s } \ rightarrow \ gamma \ gamma ) $ of roughly the desired size, mainly via the photon - fusion contribution, without involving extra colored fermions or bosons. we also discuss other major decay modes of $ \ tilde s $ which are potentially testable in upcoming lhc measurements. | arxiv:1603.01606 |
with the rapidly increasing application of large language models ( llms ), their abuse has caused many undesirable societal problems such as fake news, academic dishonesty, and information pollution. this makes ai - generated text ( aigt ) detection of great importance. among existing methods, white - box methods are generally superior to black - box methods in terms of performance and generalizability, but they require access to llms ' internal states and are not applicable to black - box settings. in this paper, we propose to estimate word generation probabilities as pseudo white - box features via multiple re - sampling to help improve aigt detection under the black - box setting. specifically, we design poger, a proxy - guided efficient re - sampling method, which selects a small subset of representative words ( e. g., 10 words ) for performing multiple re - sampling in black - box aigt detection. experiments on datasets containing texts from humans and seven llms show that poger outperforms all baselines in macro f1 under black - box, partial white - box, and out - of - distribution settings and maintains lower re - sampling costs than its existing counterparts. | arxiv:2402.09199 |
we study the equivariant cobordism theory of schemes for torus actions. we give the explicit relation between the equivariant and the ordinary cobordism of schemes with torus action. we deduce analogous results for action of arbitrary connected linear algebraic groups. we prove some structure theorems for the equivariant and ordinary cobordism of schemes with torus action and derive important consequences. we establish the localization theorems in this setting. these are used to describe the structure of the ordinary cobordism ring of certain smooth projective varieties. | arxiv:1010.6182 |
various types of sensors have been considered to develop human action recognition ( har ) models. robust har performance can be achieved by fusing multimodal data acquired by different sensors. in this paper, we introduce a new multimodal fusion architecture, referred to as unified contrastive fusion transformer ( ucfformer ) designed to integrate data with diverse distributions to enhance har performance. based on the embedding features extracted from each modality, ucfformer employs the unified transformer to capture the inter - dependency among embeddings in both time and modality domains. we present the factorized time - modality attention to perform self - attention efficiently for the unified transformer. ucfformer also incorporates contrastive learning to reduce the discrepancy in feature distributions across various modalities, thus generating semantically aligned features for information fusion. performance evaluation conducted on two popular datasets, utd - mhad and ntu rgb + d, demonstrates that ucfformer achieves state - of - the - art performance, outperforming competing methods by considerable margins. | arxiv:2309.05032 |
the magnetic dipole g _ m ( q ^ 2 ), electric quadrupole g _ e ( q ^ 2 ), and coulomb quadrupole g _ c ( q ^ 2 ) form factors, describing the spin - 3 / 2 to spin - 1 / 2 electromagnetic transitions, are investigated within the light cone qcd sum rules. the q ^ 2 dependence of these form factors, as well as ratios of electric quadrupole and coulomb quadrupole form factors to the magnetic dipole form factors are studied. we also compare our results on the magnetic dipole form factor with the prediction of the covariant spectator quark model. | arxiv:1308.0697 |
for quantum computers to become useful tools to physicists, engineers and computational scientists, quantum algorithms for solving nonlinear differential equations need to be developed. despite recent advances, the quest for a solver that can integrate nonlinear dynamical systems with a quantum advantage, whilst being realisable on available ( or near - term ) quantum hardware, is an open challenge. in this paper, we propose to transform a nonlinear dynamical system into a linear system, which we integrate with quantum algorithms. key to the method is the fokker - planck equation, which is a non - normal partial differential equation. three integration strategies are proposed : ( i ) forward - euler stepping by unitary block encoding ; ( ii ) schroedingerisation, and ( iii ) forward - euler stepping by linear addition of unitaries. we emulate the integration of prototypical nonlinear systems with the proposed quantum solvers, and compare the output with the benchmark solutions of classical integrators. we find that classical and quantum outputs are in good agreement. this paper opens opportunities for solving nonlinear differential equations with quantum algorithms. | arxiv:2401.13500 |
a survey probing respondents ' views on various foundational issues in quantum mechanics was recently created by schlosshauer, kofler, and zeilinger [ arxiv : 1301. 1069 ] and then given to 33 participants at a quantum foundations conference. here we report the results of giving this same survey to the attendees at another recent quantum foundations conference. while it is rather difficult to conclude anything of scientific significance from the poll, the results do strongly suggest several interesting cultural facts - - for example, that there exist, within the broad field of " quantum foundations ", sub - communities with quite different views, and that ( relatedly ) there is probably even significantly more controversy about several fundamental issues than the already - significant amount revealed in the earlier poll. | arxiv:1306.4646 |
technical debt ( td ) refers to delayed tasks and immature artifacts that may bring short - term benefits but incur extra costs of change during maintenance and evolution in the long term. td has been extensively studied in the past decade, and numerous open source software ( oss ) projects were used to explore specific aspects of td and validate various approaches for td management ( tdm ). however, there still lacks a comprehensive understanding on the practice of tdm in oss development, which penetrates the oss community ' s perception of the td concept and how td is managed in oss development. to this end, we conducted an empirical study on the whole github to explore the adoption and execution of tdm based on issues in oss projects. we collected 35, 278 issues labeled as td ( td issues ) distributed over 3, 598 repositories in total from the issue tracking system of github between 2009 and 2020. the findings are that : ( 1 ) the oss community is embracing the td concept ; ( 2 ) the analysis of td instances shows that td may affect both internal and external quality of software systems ; ( 3 ) only one td issue was identified in 31. 1 % of the repositories and all td issues were identified by only one developer in 69. 0 % of the repositories ; ( 4 ) tdm was ignored in 27. 3 % of the repositories after td issues were identified ; and ( 5 ) among the repositories with td labels, 32. 9 % have abandoned tdm while only 8. 2 % adopt tdm as a consistent practice. these findings provide valuable insights for practitioners in tdm and promising research directions for further investigation. | arxiv:2212.05537 |
the initial mass function ( imf ) is a construct that describes the distribution of stellar masses for a newly formed population of stars. it is a fundamental element underlying all of star and galaxy formation, and has been the subject of extensive investigation for more than 60 years. in the past few decades there has been a growing, and now substantial, body of evidence supporting the need for a variable imf. in this light, it is crucial to investigate the imf ' s characteristics across different spatial scales and to understand the factors driving its variability. we make use of spatially resolved spectroscopy to examine the high - mass imf slope of star - forming galaxies within the sami survey. by applying the kennicutt method and stellar population synthesis models, we estimated both the spaxel - resolved ( $ \ alpha _ { res } $ ) and galaxy - integrated ( $ \ alpha _ { int } $ ) high - mass imf slopes of these galaxies. our findings indicate that the resolved and integrated imf slopes exhibit a near 1 : 1 relationship for $ \ alpha _ { int } > - 2. 7 $. we observe a wide range of $ \ alpha _ { res } $ distributions within galaxies. to explore the sources of this variability, we analyse the relationships between the resolved and integrated imf slopes and both the star formation rate ( sfr ) and sfr surface density ( $ \ sigma _ { sfr } $ ). our results reveal a strong correlation where flatter / steeper slopes are associated with higher / lower sfr and $ \ sigma _ { sfr } $. this trend is qualitatively similar for resolved and global scales. additionally, we identify a mass dependency in the relationship with sfr, though none was found in the relation between the resolved slope and $ \ sigma _ { sfr } $. these findings suggest an scenario where the formation of high - mass stars is favoured in regions with more concentrated star formation. this may be a consequence of the reduced fragmentation of molecular clouds, which nonetheless accrete more material. | arxiv:2501.08510 |
results on heat current, entropy production rate and entanglement are reported for a quantum system coupled to two different temperature heat reservoirs. by applying a temperature gradient, different quantum states can be found with exactly the same amount of entanglement but different purity degrees and heat currents. furthermore, a nonequilibrium enhancement - suppression transition behavior of the entanglement is identified. | arxiv:cond-mat/0612046 |
many applications of molecular layers deposited on metal surfaces, ranging from single - atom catalysis to on - surface magnetochemistry and biosensing, rely on the use of thermal cycles to regenerate the pristine properties of the system. thus, understanding the microscopic origin behind the thermal stability of organic / metal interfaces is fundamental for engineering reliable organic - based devices. here, we study nickel porphyrin molecules on a copper surface as an archetypal system containing a metal center whose oxidation state can be controlled through the interaction with the metal substrate. we demonstrate that the strong molecule - surface interaction, followed by charge transfer at the interface, plays a fundamental role in the thermal stability of the layer by rigidly anchoring the porphyrin to the substrate. upon thermal treatment, the molecules undergo an irreversible transition at 420 k, which is associated with an increase of the charge transfer from the substrate, mostly localized on the phenyl substituents, and a downward tilting of the latters without any chemical modification | arxiv:2006.10482 |
we consider compactifications induced by the gravitino field of eleven dimensional supergravity. such compactifications are not trivial in the sense that the gravitino profiles are not related to pure bosonic ones by means of a supersymmetry transformation. the basic property of such backgrounds is that they admit $ \ psi $ - torsion although they have vanishing riemann tensor. thus, these backgrounds may be considered also as solutions of the teleparallel formulation of supergravity. we construct two classes of solutions, one with both antisymmetric three - form field, gravity and gravitino and one with only gravity and gravitino. in these classes of solutions, the internal space is a parallelized compact manifold, so that it does not inherit any cosmological constant to the external spacetime. the latter turns out to be flat minkowski in the maximally symmetric case. the elimination of the cosmological constant in the spontaneously compactified supergravity seems to be a generic property based on the trading of the cosmological constant for parallelizing torsion. | arxiv:1111.1577 |
we use the fourier operator to transform a time dependent mass quantum harmonic oscillator into a frequency dependent one. then we use lewis - ermakov invariants to solve the schr \ " odinger equation by using squeeze operators. finally we give two examples of time dependencies : quadratically and hyperbolically growing masses. | arxiv:1712.08260 |
on 2 september 2017 maxi j1535 - 571 went into outburst and peaked at ~ 5 crab in the 2 - 20 kev energy range. early in the flare integral performed target of opportunity pointings and monitored the source as it transitioned from the hard state to the soft state. using quasi - simultaneous observations from maxi / gsc and integral / spi, we studied the temporal and spectral evolution of maxi j1535 - 571 in the 2 - 500 kev range. early spectra show a comptonized spectrum and a high - energy component dominant above ~ 150 kev. comptt fits to the spi data found electron temperatures ( kte ) evolves from ~ 31 kev to 18 kev with a tied optical depth ( tau ~ 0. 85 ) or tau evolving from ~ 1. 2 - 0. 65 with a tied kte ( ~ 24 kev ). to investigate the nature of the high - energy component, we performed a spectral decomposition of the 100 - 400 kev energy band. the comptt flux varies significantly during the hard state while the high - energy component flux is consistent with a constant flux. this result suggests that the two components originate from different locations, which favors a jet origin interpretation for the high - energy component over a hybrid corona interpretation. lastly, two short rebrightenings during the hard - to - soft transition are compared to similar events reported in maxi j1820 + 070. | arxiv:2302.05346 |
we study a multiobjective variational problem on time scales. for this problem, necessary and sufficient conditions for weak local pareto optimality are given. we also prove a necessary optimality condition for the isoperimetric problem with multiple constraints on time scales. | arxiv:0801.2123 |
the dirac procedure for dealing with constraints is applied to the quantization of gauge theories on the light front. the light cone gauge is used in conjunction with the first class constraints that arise and the resulting dirac brackets are found. these gauge conditions are not used to eliminate degrees of freedom from the action prior to applying the dirac constraint procedure. this approach is illustrated by considering yang - mills theory and the superparticle in a 2 + 1 dimensional target space. | arxiv:1510.01996 |
, b ) { \ displaystyle \ gcd ( a, b ) } is often used instead. (,, ) if x, y, z are vectors in r 3 { \ displaystyle \ mathbb { r } ^ { 3 } }, then ( x, y, z ) { \ displaystyle ( x, y, z ) } may denote the scalar triple product. see also [,, ] in § square brackets. (,..., ) denotes a tuple. if there are n objects separated by commas, it is an n - tuple. (,,... ) (,...,,... ) denotes an infinite sequence. ( ) { \ displaystyle { \ begin { pmatrix } \ box & \ cdots & \ box \ \ \ vdots & \ ddots & \ vdots \ \ \ box & \ cdots & \ box \ end { pmatrix } } } denotes a matrix. often denoted with square brackets. ( ) { \ displaystyle { \ binom { \ box } { \ box } } } denotes a binomial coefficient : given two nonnegative integers, ( n k ) { \ displaystyle { \ binom { n } { k } } } is read as " n choose k ", and is defined as the integer n ( n − 1 ) ( n − k + 1 ) 1 ⋅ 2 k = n! k! ( n − k )! { \ displaystyle { \ frac { n ( n - 1 ) \ cdots ( n - k + 1 ) } { 1 \ cdot 2 \ cdots k } } = { \ frac { n! } { k! \, ( n - k )! } } } ( if k = 0, its value is conventionally 1 ). using the left - hand - side expression, it denotes a polynomial in n, and is thus defined and used for any real or complex value of n. ( ) { \ displaystyle \ left ( { \ frac { \ box } { \ box } } \ right ) } legendre symbol : if p is an odd prime number and a is an integer, the value of ( a p ) { \ displaystyle \ left ( { \ frac { a } { p } } \ right | https://en.wikipedia.org/wiki/Glossary_of_mathematical_symbols |
we study the four - terminal resistance fluctuations of mesoscopic samples near the transition between the $ \ nu = 2 $ and the $ \ nu = 1 $ quantum hall states. we observe near - perfect correlations between the fluctuations of the longitudinal and hall components of the resistance. these correlated fluctuations appear in a magnetic - field range for which the two - terminal resistance of the samples is quantized. we discuss these findings in light of edge - state transport models of the quantum hall effect. we also show that our results lead to an ambiguity in the determination of the width of quantum hall transitions. | arxiv:cond-mat/0307423 |
we describe the computation of susy - breaking terms on a d3 - brane in a quite general type iib supergravity background. we apply it to study the susy - breaking induced on the d3 - brane world - volume by the presence of nsns and rr 3 - form fluxes. we provide explicit general formulae for the susy - breaking soft terms valid for the different types of fluxes, leading to different patterns of soft terms. imaginary anti - selfdual fluxes with g _ 3 a pure ( 3, 0 ) - form lead to soft terms corresponding to dilaton - dominated susy - breaking. more general susy - breaking patterns are discussed, arising from more general fluxes, or from distant anti - d3 - branes. the known finiteness properties of dilaton - dominated soft terms are understood in terms of holography. the above results are interpreted in the context of the 4d effective supergravity theory, where flux components correspond to auxiliary fields of e. g. the 4d dilaton and overall volume modulus. we present semirealistic type iib orientifold examples with ( meta ) stable vacua leading to non - vanishing soft terms of the dilaton - domination type. such models have many of the ingredients of the recent construction of desitter vacua in string theory. we finally explore possible phenomenological applications of this form of susy - breaking, where we show that soft terms are of order m _ s ^ 2 / m _ p. thus a string scale of order m _ s = 10 ^ { 10 } gev, and compactification scale three orders of magnitude smaller could explain the smallness of the weak scale versus the planck mass. | arxiv:hep-th/0311241 |
we propose an auxiliary - bath algorithm for the numerical renormalization group ( nrg ) method to solve multi - impurity models with shared electron baths. the method allows us to disentangle the electron baths into independent wilson chains to perform standard nrg procedures beyond the widely adopted independent bath approximation. its application to the 2 - impurity model immediately reproduces the well - known even - and odd - parity channels. for 3 - impurity kondo models, we find successive screening of collective degrees of freedom such as the helicity and the cluster spin, and clarify the false prediction of a non - fermi liquid ground state in unphysical parameter region in previous literature due to improper treatment of disentanglement. our work highlights the importance of nonlocal spatial correlations due to shared baths and reveals a generic picture of successive collective screening for the entropy depletion that is crucial in real correlated systems. our method greatly expands the applicability of the nrg and opens an avenue for its further development. | arxiv:2305.10297 |
recently, the membership inference attack poses a serious threat to the privacy of confidential training data of machine learning models. this paper proposes a novel adversarial example based privacy - preserving technique ( aeppt ), which adds the crafted adversarial perturbations to the prediction of the target model to mislead the adversary ' s membership inference model. the added adversarial perturbations do not affect the accuracy of target model, but can prevent the adversary from inferring whether a specific data is in the training set of the target model. since aeppt only modifies the original output of the target model, the proposed method is general and does not require modifying or retraining the target model. experimental results show that the proposed method can reduce the inference accuracy and precision of the membership inference model to 50 %, which is close to a random guess. further, for those adaptive attacks where the adversary knows the defense mechanism, the proposed aeppt is also demonstrated to be effective. compared with the state - of - the - art defense methods, the proposed defense can significantly degrade the accuracy and precision of membership inference attacks to 50 % ( i. e., the same as a random guess ) while the performance and utility of the target model will not be affected. | arxiv:2011.13696 |
we consider the situation where multiple transportation service providers cooperate to offer an integrated multi - modal platform to enhance the convenience to the passengers through ease in multi - modal journey planning, payment, and first and last mile connectivity. this market structure allows the multi - modal platform to coordinate profits across modes and also provide incentives to the passengers. accordingly, in this paper, we use cooperative game theory coupled with the hyperpath - based stochastic user equilibrium framework to study such a market. we assume that the platform sets incentives ( price discount or excess charge on passengers ) along every edge in the transportation network. we derive the continuity and monotonicity properties of the equilibrium flow with respect to the incentives along every edge. the optimal incentives that maximize the profit of the platform are obtained through a two time - scale stochastic approximation algorithm. we use the asymmetric nash bargaining solution to design a fair profit sharing scheme among the service providers. we show that the profit for each service provider increases after cooperation on such a platform. finally, we complement the theoretical results through two numerical simulations. | arxiv:2101.03297 |
we classify the volume preserving stable hypersurfaces in the real projective space $ \ mathbb { rp } ^ n $. as a consequence, the solutions of the isoperimetric problem are tubular neighborhoods of projective subspaces $ \ mathbb { rp } ^ k \ subset \ mathbb { rp } ^ n $ ( starting with points ). this confirms a conjecture of burago and zalgaller from 1988 and extends to higher dimensions previous result of m. ritor \ ' { e } and a. ros on $ \ mathbb { rp } ^ 3 $. we also derive an willmore type inequality for antipodal invariant hypersurfaces in $ \ mathbb { s } ^ n $. | arxiv:1907.09445 |
we present very long baseline interferometry polarization images of an x - ray selected sample of bl lacertae objects belonging to the first high energy astronomy observatory ( heao - 1 ) and the rosat - green bank ( rgb ) surveys. these are primarily high - energy - peaked bl lacs ( hbls ) and exhibit core - jet radio morphologies on pc - scales. they show moderately polarized jet components, similar to those of low - energy - peaked bl lacs ( lbls ). the fractional polarization in the unresolved cores of the hbls is, on average, lower than in the lbls, while the fractional polarizations in the pc - scale jets of hbls and lbls are comparable. however a difference is observed in the orientation of the inferred jet magnetic fields - - while lbl jets are well - known to preferentially exhibit transverse magnetic fields, the hbl jets tend to display longitudinal magnetic fields. although a ` spine - sheath ' jet velocity structure, along with larger viewing angles for hbls could produce the observed magnetic field configuration, differences in other properties of lbls and hbls, such as their total radio power, cannot be fully reconciled with the different - angle scenario alone. instead it appears that lbls and hbls differ intrinsically, perhaps in the spin rates of their central black holes. | arxiv:0711.1158 |
we prove a conjecture of griffiths on simultaneous normalization of all periods which asserts that the image of the lifted period map on the universal cover lies in a bounded domain in complex euclidean space. | arxiv:1412.2837 |
generative learning is a powerful tool for representation learning, and shows particular promise for problems in biomedical imaging. however, in this context, sampling from the distribution is secondary to finding representations of real images, which often come with labels and explicitly represent the content and quality of the target distribution. it remains difficult to faithfully reconstruct images from generative models, particularly those as complex as histological images. in this work, two existing methods ( autoencoders and adversarial latent autoencoders ) are combined in attempt to improve our ability to encode and decode real images of non - melanoma skin cancer, specifically intra - epidermal carcinoma ( iec ). utilising a dataset of high - quality images of iec ( 256 x 256 ), this work assesses the result of both image reconstruction quality and representation learning. it is shown that adversarial training can improve baseline fid scores from 76 to 50, and that benchmarks on representation learning can be improved by up to 3 %. smooth and realistic interpolations of the variation in the morphological structure are also presented for the first time, positioning representation learning as a promising direction in the context of computational pathology. | arxiv:2209.01779 |
we advance a class of unitary higher derivative theories of gravity that realize an ultraviolet completion of einstein general relativity in any dimension. this range of theories is marked by an entire function, which averts extra degrees of freedom ( including poltergeists ) and improves the high energy behavior of the loop amplitudes. it is proved that only one - loop divergences survive and the theory can be made super - renormalizable regardless of the spacetime dimension. moreover, using the pauli - villars regularization procedure introduced by diaz - troost - van nieuwenhuizen - van proeyen ( dtpn ) and applied to einstein ' s gravity by anselmi, we are able to remove the divergences also at one - loop, making the theory completely finite in any dimension as expected by anselmi and asorey - lopez - shapiro. | arxiv:1402.6795 |
the autologistic actor attribute model, or alaam, is the social influence counterpart of the better - known exponential - family random graph model ( ergm ) for social selection. extensive experience with ergms has shown that the problem of near - degeneracy which often occurs with simple models can be overcome by using " geometrically weighted " or " alternating " statistics. in the much more limited empirical applications of alaams to date, the problem of near - degeneracy, although theoretically expected, appears to have been less of an issue. in this work i present a comprehensive survey of alaam applications, showing that this model has to date only been used with relatively small networks, in which near - degeneracy does not appear to be a problem. i show near - degeneracy does occur in simple alaam models of larger empirical networks, define some geometrically weighted alaam statistics analogous to those for ergm, and demonstrate that models with these statistics do not suffer from near - degeneracy and hence can be estimated where they could not be with the simple statistics. | arxiv:2309.07338 |
people can learn a wide range of tasks from their own experience, but can also learn from observing other creatures. this can accelerate acquisition of new skills even when the observed agent differs substantially from the learning agent in terms of morphology. in this paper, we examine how reinforcement learning algorithms can transfer knowledge between morphologically different agents ( e. g., different robots ). we introduce a problem formulation where two agents are tasked with learning multiple skills by sharing information. our method uses the skills that were learned by both agents to train invariant feature spaces that can then be used to transfer other skills from one agent to another. the process of learning these invariant feature spaces can be viewed as a kind of " analogy making ", or implicit learning of partial correspondences between two distinct domains. we evaluate our transfer learning algorithm in two simulated robotic manipulation skills, and illustrate that we can transfer knowledge between simulated robotic arms with different numbers of links, as well as simulated arms with different actuation mechanisms, where one robot is torque - driven while the other is tendon - driven. | arxiv:1703.02949 |
we overview some attempts to find s - duality analogues of non - supersymmetric yang - mills theory, in the context of gravity theories. the case of macdowell - mansouri gauge theory of gravity is discussed. three - dimensional dimensional reductions from the topological gravitational sector in four dimensions, enable to recuperate the 2 + 1 chern - simons gravity and the corresponding s - dual theory, from the notion of self - duality in the four - dimensional theory. | arxiv:hep-th/0003083 |
in these lecture notes we will consider systems in which the motion of electrons is confined to one dimension ( 1d ). in these so - called quantum wires electron - electron interaction effects play an important role because the restricted dimensions enhance the scattering between the electrons and completely destroy the quasi - particle picture. new density wave excitations appear that are described by bosonic operators. here, we will develop this bosonic description, following a pedestrian approach which does not require any previous knowledge in field theory methods. these notes therefore serve as a detailed introduction into bosonization by carefully deriving the most fundamental formulas. | arxiv:0708.0003 |
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. | arxiv:1908.03852 |
quantum harmonic oscillators, or qumodes, provide a promising and versatile framework for quantum computing. unlike qubits, which are limited to two discrete levels, qumodes have an infinite - dimensional hilbert space, making them well - suited for a wide range of quantum simulations. in this work, we focus on the molecular electronic structure problem. we propose an approach to map the electronic hamiltonian into a qumode bosonic problem that can be solved on bosonic quantum devices using the variational quantum eigensolver ( vqe ). our approach is demonstrated through the computation of ground potential energy surfaces for benchmark model systems, including h $ _ 2 $ and the linear h $ _ 4 $ molecule. the preparation of trial qumode states and the computation of expectation values leverage universal ansatzes based on the echoed conditional displacement ( ecd ), or the selective number - dependent arbitrary phase ( snap ) operations. these techniques are compatible with circuit quantum electrodynamics ( cqed ) platforms, where microwave resonators coupled to superconducting transmon qubits can offer an efficient hardware realization. this work establishes a new pathway for simulating many - fermion systems, highlighting the potential of hybrid qubit - qumode quantum devices in advancing quantum computational chemistry. | arxiv:2404.10222 |
xmass - i is a single - phase liquid xenon detector whose purpose is direct detection of dark matter. to achieve the low background requirements necessary in the detector, a new model of photomultiplier tubes ( pmts ), r10789, with a hexagonal window was developed based on the r8778 pmt used in the xmass prototype detector. we screened the numerous component materials for their radioactivity. during development, the largest contributions to the reduction of radioactivity came from the stem and the dynode support. the glass stem was exchanged to the kovar alloy one and the ceramic support were changed to the quartz one. r10789 is the first model of hamamatsu photonics k. k. that adopted these materials for low background purposes and provided a groundbreaking step for further reductions of radioactivity in pmts. measurements with germanium detectors showed 1. 2 $ \ pm $ 0. 3 mbq / pmt of $ ^ { 226 } $ ra, less than 0. 78 mbq / pmt of $ ^ { 228 } $ ra, 9. 1 $ \ pm $ 2. 2 mbq / pmt of $ ^ { 40 } $ k, and 2. 8 $ \ pm $ 0. 2 mbq / pmt of $ ^ { 60 } $ co. in this paper, the radioactive details of the developed r10789 are described together with our screening methods and the components of the pmt. | arxiv:1808.03617 |
we present a new, fully covariant and manifestly gauge - invariant expression for the temperature anisotropy in the cosmic microwave background radiation resulting from scalar perturbations. we pay particular attention to gauge issues such as the definition of the temperature perturbation and the placing of the last scattering surface. in the instantaneous recombination approximation, the expression may be integrated up to a rees - sciama term for arbitrary matter descriptions in flat, open and closed universes. we discuss the interpretation of our result in the baryon - dominated limit using numerical solutions for conditions on the last scattering surface, and confirm that for adiabatic perturbations the dominant contribution to the anisotropy on intermediate scales ( the location of the doppler peaks ) may be understood in terms of the spatial inhomogeneity of the radiation temperature in the baryon rest frame. finally, we show how this term enters the usual sachs - wolfe type calculations ( it is rarely seen in such analyses ) when subtle gauge effects at the last scattering surface are treated correctly. | arxiv:astro-ph/9804150 |
recent advancements in large language models ( llms ) have opened new pathways for many domains. however, the full potential of llms in financial investments remains largely untapped. there are two main challenges for typical deep learning - based methods for quantitative finance. first, they struggle to fuse textual and numerical information flexibly for stock movement prediction. second, traditional methods lack clarity and interpretability, which impedes their application in scenarios where the justification for predictions is essential. to solve the above challenges, we propose ploutos, a novel financial llm framework that consists of ploutosgen and ploutosgpt. the ploutosgen contains multiple primary experts that can analyze different modal data, such as text and numbers, and provide quantitative strategies from different perspectives. then ploutosgpt combines their insights and predictions and generates interpretable rationales. to generate accurate and faithful rationales, the training strategy of ploutosgpt leverage rearview - mirror prompting mechanism to guide gpt - 4 to generate rationales, and a dynamic token weighting mechanism to finetune llm by increasing key tokens weight. extensive experiments show our framework outperforms the state - of - the - art methods on both prediction accuracy and interpretability. | arxiv:2403.00782 |
the euronu super beam work package has studied a neutrino beam based on spl at cern and aimed at memphys, a large water cherenkov detector, proposed for the laboratoire souterrain de modane ( fr \ ' ejus tunnel, france ), with a baseline of 130 km. the aim of this proposed experiment is to study the cp violation in the neutrino sector. in the study reported here, we have developed the conceptual design of the neutrino beam, especially the target and the magnetic focusing device. indeed, this beam present several unprecedented challenges, like the high primary proton beam power ( 4 mw ), the high repetition rate ( 50 hz ) and the low energy of the protons ( 4. 5 gev ). the design is completed by a study of all the main component of the system, starting from the transport system to guide the beam to the target up to the beam dump. | arxiv:1212.0732 |
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