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in a recent paper published in pnas authors prove that locality and free choice are equivalent resources which need to be relaxed in order to fully reproduce some statistics in bell experiments ( while always maintaining realism ). we explain that their assumption of free choice is simply counterfactual definiteness or noncontextuality. therefore the resource in bell experiments is contextuality and not the violations of locality and / or of free choice. it is definitely less mind boggling conclusion because experimenters ` freedom of choice is a prerequisite of science,
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arxiv:2105.14279
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one of the most surprising consequences of quantum mechanics is the entanglement of two or more distant particles. in an entangled epr two - particle system, the value of the momentum ( position ) for neither single subsystem is determined. however, if one of the subsystems is measured to have a certain momentum ( position ), the other subsystem is determined to have a unique corresponding value, despite the distance between them. this peculiar behavior of an entangled quantum system has surprisingly been observed experimentally in two - photon temporal and spatial correlation measurements, such as ghost interference and ghost imaging. this article addresses the fundamental concerns behind these experimental observations and to explore the nonclassical nature of two - photon superposition by emphasizing the physics of 2 is not 1 + 1.
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arxiv:0706.2097
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we show that the m \ " obius disjointess of zero entropy dynamical systems implies the existence of an increasing sequence of positive integers along which the chowla conjecture on autocorrelations of the m \ " obius function holds.
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arxiv:1710.07049
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the lmc star, sstisage1c j050756. 44 - 703453. 9, was first noticed during a survey of eros - 2 lightcurves for stars with large irregular brightness variations typical of the r coronae borealis ( rcb ) class. however, the visible spectrum showing emission lines including the balmer and paschen series as well as many fe ii lines is emphatically not that of an rcb star. this star has all of the characteristics of a typical ux ori star. it has a spectral type of approximately a2 and has excited an h ii region in its vicinity. however, if it is an lmc member, then it is very luminous for a herbig ae / be star. it shows irregular drops in brightness of up to 2 mag, and displays the reddening and " blueing " typical of this class of stars. its spectrum, showing a combination of emission and absorption lines, is typical of a ux ori star that is in a decline caused by obscuration from the circumstellar dust. sstisage1c j050756. 44 - 703453. 9 has a strong ir excess and significant emission is present out to 500 micron. monte carlo radiative transfer modeling of the sed requires that sstisage1c j050756. 44 - 703453. 9 has both a dusty disk as well as a large extended diffuse envelope to fit both the mid - and far - ir dust emission. this star is a new member of the ux ori subclass of the herbig ae / be stars and only the second such star to be discovered in the lmc.
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arxiv:1008.1945
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this paper introduces a method for the nonparametric bayesian learning of nonlinear operators, through the use of the volterra series with kernels represented using gaussian processes ( gps ), which we term the nonparametric volterra kernels model ( nvkm ). when the input function to the operator is unobserved and has a gp prior, the nvkm constitutes a powerful method for both single and multiple output regression, and can be viewed as a nonlinear and nonparametric latent force model. when the input function is observed, the nvkm can be used to perform bayesian system identification. we use recent advances in efficient sampling of explicit functions from gps to map process realisations through the volterra series without resorting to numerical integration, allowing scalability through doubly stochastic variational inference, and avoiding the need for gaussian approximations of the output processes. we demonstrate the performance of the model for both multiple output regression and system identification using standard benchmarks.
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arxiv:2106.05582
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in this article we study the stability problem for the einstein metrics on sasaki einstein and on complete nearly parallel $ { \ rm g } _ 2 $ manifolds. in the sasaki case we show linear instability if the second betti number is positive. similarly we prove that nearly parallel $ \ rm g _ 2 $ manifolds with positive third betti number are linearly unstable. moreover, we prove linear instability for the berger space $ { \ rm so } ( 5 ) / { \ rm so } ( 3 ) _ { irr } $ which is a $ 7 $ - dimensional homology sphere with a proper nearly parallel $ { \ rm g } _ 2 $ structure.
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arxiv:2011.11965
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while neural networks have been used extensively to make substantial progress in the machine translation task, they are known for being heavily dependent on the availability of large amounts of training data. recent efforts have tried to alleviate the data sparsity problem by augmenting the training data using different strategies, such as back - translation. along with the data scarcity, the out - of - vocabulary words, mostly entities and terminological expressions, pose a difficult challenge to neural machine translation systems. in this paper, we hypothesize that knowledge graphs enhance the semantic feature extraction of neural models, thus optimizing the translation of entities and terminological expressions in texts and consequently leading to a better translation quality. we hence investigate two different strategies for incorporating knowledge graphs into neural models without modifying the neural network architectures. we also examine the effectiveness of our augmentation method to recurrent and non - recurrent ( self - attentional ) neural architectures. our knowledge graph augmented neural translation model, dubbed kg - nmt, achieves significant and consistent improvements of + 3 bleu, meteor and chrf3 on average on the newstest datasets between 2014 and 2018 for wmt english - german translation task.
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arxiv:1902.08816
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in this work we propose a discretization of the second boundary condition for the monge - ampere equation arising in geometric optics and optimal transport. the discretization we propose is the natural generalization of the popular oliker - prussner method proposed in 1988. for the discretization of the differential operator, we use a discrete analogue of the subdifferential. existence, unicity and stability of the solutions to the discrete problem are established. convergence results to the continuous problem are given.
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arxiv:1910.14376
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this paper introduces a novel choquet distance using fuzzy rough set based measures. the proposed distance measure combines the attribute information received from fuzzy rough set theory with the flexibility of the choquet integral. this approach is designed to adeptly capture non - linear relationships within the data, acknowledging the interplay of the conditional attributes towards the decision attribute and resulting in a more flexible and accurate distance. we explore its application in the context of machine learning, with a specific emphasis on distance - based classification approaches ( e. g. k - nearest neighbours ). the paper examines two fuzzy rough set based measures that are based on the positive region. moreover, we explore two procedures for monotonizing the measures derived from fuzzy rough set theory, making them suitable for use with the choquet integral, and investigate their differences.
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arxiv:2403.11843
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this study focuses on addressing the inverse source problem associated with the parabolic equation. we rely on sparse boundary flux data as our measurements, which are acquired from a restricted section of the boundary. while it has been established that utilizing sparse boundary flux data can enable source recovery, the presence of a limited number of observation sensors poses a challenge for accurately tracing the inverse quantity of interest. to overcome this limitation, we introduce a sampling algorithm grounded in langevin dynamics that incorporates dynamic sensors to capture the flux information. furthermore, we propose and discuss two distinct sensor migration strategies. remarkably, our findings demonstrate that even with only two observation sensors at our disposal, it remains feasible to successfully reconstruct the high - dimensional unknown parameters.
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arxiv:2310.01541
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model compression methods are important to allow for easier deployment of deep learning models in compute, memory and energy - constrained environments such as mobile phones. knowledge distillation is a class of model compression algorithm where knowledge from a large teacher network is transferred to a smaller student network thereby improving the student ' s performance. in this paper, we show how optimal transport - based loss functions can be used for training a student network which encourages learning student network parameters that help bring the distribution of student features closer to that of the teacher features. we present image classification results on cifar - 100, svhn and imagenet and show that the proposed optimal transport loss functions perform comparably to or better than other loss functions.
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arxiv:2012.03907
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of a robot that resembles humans is sophia, a social humanoid robot developed by hong kong - based company hanson robotics which was activated on april 19, 2015. many of today ' s robots are inspired by nature contributing to the field of bio - inspired robotics. = = = stem - cell therapy = = = stem cell therapy is an intervention strategy that introduces new adult stem cells into damaged tissue in order to treat disease or injury. many medical researchers believe that stem cell treatments have the potential to change the face of human disease and alleviate suffering. the ability of stem cells to self - renew and give rise to subsequent generations with variable degrees of differentiation capacities offers significant potential for generation of tissues that can potentially replace diseased and damaged areas in the body, with minimal risk of rejection and side effects. chimeric antigen receptor ( car ) - modified t cells have raised among other immunotherapies for cancer treatment, being implemented against b - cell malignancies. despite the promising outcomes of this innovative technology, car - t cells are not exempt from limitations that must yet to be overcome in order to provide reliable and more efficient treatments against other types of cancer. = = = distributed ledger technology = = = distributed ledger or blockchain technology provides a transparent and immutable list of transactions. a wide range of uses has been proposed for where an open, decentralised database is required, ranging from supply chains to cryptocurrencies. smart contracts are self - executing transactions which occur when pre - defined conditions are met. the aim is to provide security that is superior to traditional contract law, and to reduce transaction costs and delays. the original idea was conceived by nick szabo in 1994, but remained unrealised until the development of blockchains. = = = augmented reality = = = this type of technology where digital graphics are loaded onto live footage has been around since the 20th century, but thanks to the arrival of more powerful computing hardware and the implementation of open source, this technology has been able to do things that we never thought were possible. some ways in which we have used this technology can be through apps such as pokemon go, snapchat and instagram filters and other apps that create fictional things in real objects. = = = multi - use rockets = = = reusable rockets, in contrast to single use rockets that are disposed after launch, are able to propulsively land safely in a pre - specified place where they are recovered to be used again in later launches. early prototypes include the mcdonnell douglas dc - x tested
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https://en.wikipedia.org/wiki/Emerging_technologies
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the human visual system is composed of multiple physiological components that apply multiple mechanisms in order to cope with the rich visual content it encounters. the complexity of this system leads to non - trivial relations between what we see and what we perceive, and in particular, between the raw intensities of an image that we display and the ones we perceive where various visual biases and illusions are introduced. in this paper we describe a method for reducing a large class of biases related to the lateral inhibition mechanism in the human retina where neurons suppress the activity of neighboring receptors. among these biases are the well - known mach bands and halos that appear around smooth and sharp image gradients as well as the appearance of false contrasts between identical regions. the new method removes these visual biases by computing an image that contains counter biases such that when this laterally - compensated image is viewed on a display, the inserted biases cancel the ones created in the retina.
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arxiv:1904.05614
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model - based reinforcement learning ( rl ) algorithms designed for handling complex visual observations typically learn some sort of latent state representation, either explicitly or implicitly. standard methods of this sort do not distinguish between functionally relevant aspects of the state and irrelevant distractors, instead aiming to represent all available information equally. we propose a modified objective for model - based rl that, in combination with mutual information maximization, allows us to learn representations and dynamics for visual model - based rl without reconstruction in a way that explicitly prioritizes functionally relevant factors. the key principle behind our design is to integrate a term inspired by variational empowerment into a state - space model based on mutual information. this term prioritizes information that is correlated with action, thus ensuring that functionally relevant factors are captured first. furthermore, the same empowerment term also promotes faster exploration during the rl process, especially for sparse - reward tasks where the reward signal is insufficient to drive exploration in the early stages of learning. we evaluate the approach on a suite of vision - based robot control tasks with natural video backgrounds, and show that the proposed prioritized information objective outperforms state - of - the - art model based rl approaches with higher sample efficiency and episodic returns. https : / / sites. google. com / view / information - empowerment
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arxiv:2204.08585
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gabidulin codes, serving as the rank - metric counterpart of reed - solomon codes, constitute an important class of maximum rank distance ( mrd ) codes. however, unlike the fruitful positive results about the list decoding of reed - solomon codes, results concerning the list decodability of gabidulin codes in the rank metric are all negative so far. for example, in contrast to reed - solomon codes, which are always list decodable up to the johnson bound in the hamming metric, raviv and wachter - zeh ( ieee tit, 2016 and 2017 ) constructed a class of gabidulin codes that are not even combinatorially list decodable beyond the unique decoding radius in the rank metric. proving the existence of gabidulin codes with good combinatorial list decodability in the rank metric has remained a long - standing open problem. in this paper, we resolve the aforementioned open problem by showing that, with high probability, random gabidulin codes over sufficiently large alphabets attain the optimal generalized singleton bound for list decoding in the rank metric. in particular, they achieve list decoding capacity in the rank metric. our work is significantly influenced by the recent breakthroughs in the combinatorial list decodability of reed - solomon codes, especially the work by brakensiek, gopi, and makam ( stoc 2023 ). our major technical contributions, which may hold independent interest, consist of the following : ( 1 ) we initiate the study of ` ` higher order mrd codes ' ' and provide a novel unified theory, which runs parallel to the theory of ` ` higher order mds codes ' ' developed by bgm. ( 2 ) we prove a natural analog of the gm - mds theorem, proven by lovett ( focs 2018 ) and yildiz and hassibi ( ieee tit, 2019 ), which we call the gm - mrd theorem. in particular, our gm - mrd theorem for gabidulin codes are strictly stronger than the gm - mds theorem for gabidulin codes, proven by yildiz and hassibi ( ieee tit, 2019 ).
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arxiv:2404.13230
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the purpose of this paper is to show how a congruence between ( the fourier coefficients of ) a hilbert cusp form and a hilbert eisenstein series of parallel weight $ 2 $ gives rise to congruences between algebraic parts of critical values of their $ l $ - functions. this is a generalization of a result of v. vatsal.
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arxiv:1707.01314
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the aim of this article is to prove that the torelli group action on the g - character varieties is ergodic for g a connected, semi - simple and compact lie group.
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arxiv:2001.08397
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the collective behaviour of statistical systems close to critical points is characterized by an extremely slow dynamics which, in the thermodynamic limit, eventually prevents them from relaxing to an equilibrium state after a change in the thermodynamic control parameters. the non - equilibrium evolution following this change displays some of the features typically observed in glassy materials, such as ageing, and it can be monitored via dynamic susceptibilities and correlation functions of the order parameter, the scaling behaviour of which is characterized by universal exponents, scaling functions, and amplitude ratios. this universality allows one to calculate these quantities in suitable simplified models and field - theoretical methods are a natural and viable approach for this analysis. in addition, if a statistical system is spatially confined, universal casimir - like forces acting on the confining surfaces emerge and they build up in time when the temperature of the system is tuned to its critical value. we review here some of the theoretical results that have been obtained in recent years for universal quantities, such as the fluctuation - dissipation ratio, associated with the non - equilibrium critical dynamics, with particular focus on the ising model with glauber dynamics in the bulk. the non - equilibrium dynamics of the casimir force acting in a film is discussed within the gaussian model.
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arxiv:0712.1213
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we have loaded an ultracold gas of fermionic atoms into a far off resonance optical dipole trap and precisely controlled the spin composition of the trapped gas. we have measured a magnetic - field feshbach resonance between atoms in the two lowest energy spin - states, | 9 / 2, - 9 / 2 > and | 9 / 2, - 7 / 2 >. the resonance peaks at a magnetic field of 201. 5 plus or minus 1. 4 g and has a width of 8. 0 plus or minus 1. 1 g. using this resonance we have changed the elastic collision cross section in the gas by nearly 3 orders of magnitude.
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arxiv:cond-mat/0111571
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true. 3. sometimes denotes the top element of a bounded lattice ( previous meanings are specific examples ). 4. for the use as a superscript, see. ( up tack ) 1. { \ displaystyle \ bot } denotes the logical predicate always false. 2. denotes also the truth value false. 3. sometimes denotes the bottom element of a bounded lattice ( previous meanings are specific examples ). 4. in cryptography often denotes an error in place of a regular value. 5. for the use as a superscript, see. 6. for the similar symbol, see { \ displaystyle \ perp }. = = blackboard bold = = the blackboard bold typeface is widely used for denoting the basic number systems. these systems are often also denoted by the corresponding uppercase bold letter. a clear advantage of blackboard bold is that these symbols cannot be confused with anything else. this allows using them in any area of mathematics, without having to recall their definition. for example, if one encounters r { \ displaystyle \ mathbb { r } } in combinatorics, one should immediately know that this denotes the real numbers, although combinatorics does not study the real numbers ( but it uses them for many proofs ). n { \ displaystyle \ mathbb { n } } denotes the set of natural numbers { 1, 2, … }, { \ displaystyle \ { 1, 2, \ ldots \ }, } or sometimes { 0, 1, 2, … }. { \ displaystyle \ { 0, 1, 2, \ ldots \ }. } when the distinction is important and readers might assume either definition, n 1 { \ displaystyle \ mathbb { n } _ { 1 } } and n 0 { \ displaystyle \ mathbb { n } _ { 0 } } are used, respectively, to denote one of them unambiguously. notation n { \ displaystyle \ mathbf { n } } is also commonly used. z { \ displaystyle \ mathbb { z } } denotes the set of integers { …, − 2, − 1, 0, 1, 2, … }. { \ displaystyle \ { \ ldots, - 2, - 1, 0, 1, 2, \ ldots \ }. } it is often denoted also by z. { \ displaystyle \ mathbf { z }. } z p { \ displaystyle \ mathbb { z } _ {
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https://en.wikipedia.org/wiki/Glossary_of_mathematical_symbols
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some examples and basic properties of ultrametric spaces are briefly discussed.
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arxiv:0711.0709
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in the present paper we study the thermodynamical properties of finitely generated continuous subgroup actions. we address a notion of topological entropy and pressure functions that does not depend on the growth rate of the semigroup and introduce strong and orbital specification properties, under which, the semigroup actions have positive topological entropy and all points are entropy points. moreover, we study the convergence and lipschitz regularity of the pressure function and obtain relations between topological entropy and exponential growth rate of periodic points in the context of semigroups of expanding maps. the specification properties for semigroup actions and the corresponding one for its generators and the action of push - forward maps is also discussed.
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arxiv:1502.01163
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the commutator $ [ x ( t ), p ] $ in an inverted harmonic oscillator ( iho ) in one - dimensional quantum mechanics exhibits remarkable properties. it reduces to a c - number and does not show any quantum fluctuations for arbitrary states. related to this nature, the quantum lyapunov exponent computed through the out - of - time - order correlator ( otoc ) $ \ langle [ x ( t ), p ] ^ 2 \ rangle $ precisely agrees with the classical one. hence, the otoc may be regarded as an ideal indicator of the butterfly effect in the iho. since ihos are ubiquitous in physics, these properties of the commutator $ [ x ( t ), p ] $ and the otocs might be seen in various situations, too. in order to clarify this point, as a first step, we investigate otocs in one - dimensional quantum mechanics with polynomial potentials, which exhibit butterfly effects around the peak of the potential in classical mechanics. we find two situations in which the otocs show exponential growth reproducing the classical lyapunov exponent of the peak. the first one, which is obvious, is using a suitably localized wave packet near the peak, and the second one is taking a limit akin to the large - $ n $ limit in the noncritical string theories.
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arxiv:2105.09603
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manifold x. in this case, one considers the algebra of holomorphic functions, i. e., complex differentiable functions. their ratios form the field of meromorphic functions on x. the function field of an algebraic variety x ( a geometric object defined as the common zeros of polynomial equations ) consists of ratios of regular functions, i. e., ratios of polynomial functions on the variety. the function field of the n - dimensional space over a field f is f ( x1,..., xn ), i. e., the field consisting of ratios of polynomials in n indeterminates. the function field of x is the same as the one of any open dense subvariety. in other words, the function field is insensitive to replacing x by a ( slightly ) smaller subvariety. the function field is invariant under isomorphism and birational equivalence of varieties. it is therefore an important tool for the study of abstract algebraic varieties and for the classification of algebraic varieties. for example, the dimension, which equals the transcendence degree of f ( x ), is invariant under birational equivalence. for curves ( i. e., the dimension is one ), the function field f ( x ) is very close to x : if x is smooth and proper ( the analogue of being compact ), x can be reconstructed, up to isomorphism, from its field of functions. in higher dimension the function field remembers less, but still decisive information about x. the study of function fields and their geometric meaning in higher dimensions is referred to as birational geometry. the minimal model program attempts to identify the simplest ( in a certain precise sense ) algebraic varieties with a prescribed function field. = = = number theory : global fields = = = global fields are in the limelight in algebraic number theory and arithmetic geometry. they are, by definition, number fields ( finite extensions of q ) or function fields over fq ( finite extensions of fq ( t ) ). as for local fields, these two types of fields share several similar features, even though they are of characteristic 0 and positive characteristic, respectively. this function field analogy can help to shape mathematical expectations, often first by understanding questions about function fields, and later treating the number field case. the latter is often more difficult. for example, the riemann hypothesis concerning the zeros of the riemann zeta function ( open as of 2017 ) can be regarded as being parallel to the weil conjectures ( proven
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https://en.wikipedia.org/wiki/Field_(mathematics)
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we introduce a novel coupling potential for the scattering of deformed light heavy - ion reactions. this new approach is based on replacing the usual first - derivative coupling potential by a new, second derivative coupling potential in the coupled - channels formalism. the new approach has been successfully applied to the study of the $ ^ { 12 } $ c + $ ^ { 12 } $ c, $ ^ { 12 } $ c + $ ^ { 24 } $ mg, $ ^ { 16 } $ o + $ ^ { 28 } $ si and $ ^ { 16 } $ o + $ ^ { 24 } $ mg systems and made major improvements over all the previous coupled - channels calculations for these systems. this paper also shows the limitations of the standard coupled - channels theory and presents a global solution to the problems faced in the previous theoretical accounts of these reactions.
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arxiv:nucl-th/0209006
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the healing of graphene grown from a metallic substrate is investigated using tight - binding monte carlo simulations. at temperatures ( ranging from 1000 to 2500 k ), an isolated graphene sheet can anneal a large number of defects suggesting that their healing are thermally activated. we show that in presence of a nickel substrate we obtain a perfect graphene layer. the nickel - carbon chemical bonds keep breaking and reforming around defected carbon zones, providing a direct interaction, necessary for the healing. thus, the action of ni atoms is found to play a key role in the reconstruction of the graphene sheet by annealing defects.
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arxiv:1009.0192
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we study, by incorporating short - range ion - surface interactions, ionic profiles of electrolyte solutions close to a non - charged interface between two dielectric media. in order to account for important correlation effects close to the interface, the ionic profiles are calculated beyond mean - field theory, using the loop expansion of the free energy. we show how it is possible to overcome the well - known deficiency of the regular loop expansion close to the dielectric jump, and treat the non - linear boundary conditions within the framework of field theory. the ionic profiles are obtained analytically to one - loop order in the free energy, and their dependence on different ion - surface interactions is investigated. the gibbs adsorption isotherm, as well as the ionic profiles are used to calculate the surface tension, in agreement with the reverse hofmeister series. consequently, from the experimentally - measured surface tension, one can extract a single adhesivity parameter, which can be used within our model to quantitatively predict hard to measure ionic profiles.
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arxiv:1607.06375
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we improve the algorithm to noninvasively update the response matrix using information from the orbit - feedback system, described in [ 1 ]. the new version is capable of adapting to slow changes of the lattice, albeit at the expense of limiting the accuracy.
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arxiv:2303.11216
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this paper introduces a statistical treatment to use cepheid variable stars as distance indicators. the expansion rate of the universe is also studied here through deriving the value of the hubble constant h0. a gaussian function approximation is proposed to fit the absolute magnitude and period of cepheid variables in our galaxy. the calculations are carried out on samples of cepheids observed in 23 galaxies to derive the distance modulus ( dm ) of these galaxies based on the frequency distributions of their periods and intrinsic apparent magnitudes. the dm is the difference between the apparent magnitude for extragalactic cepheids and the absolute magnitude of the galactic cepheids at maximum number. it is calculated by using the comparison of the period distribution of cepheids in our galaxy and in other galaxies. this method is preferred due to its simplicity to use and its efficiency in providing reliable dm. a linear fit with correlation coefficient of 99. 68 % has been found between the published distance modulus and that computed one in the present work. from the present sample, a value of h0 in the range of 66 to 80 + / - 5 km / s mpc is determined. the present procedure of computation and its accuracy are confirmed by the high correlation found between our computed dm and that published in the literature.
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arxiv:1409.4168
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twin boundaries are generic crystalline defects in noncentrosymmetric crystal structures. we study theoretically twin boundaries in time - reversal symmetric noncentrosymmetric superconductors that admit parity - mixed cooper pairing. twin boundaries support spin currents as a consequence of this parity mixing. if the singlet and triplet components of the superconducting order parameter are of comparable magnitude, the superconducting state breaks spontaneously the bulk time - reversal symmetry locally near the twin boundary. by self - consistently evaluating the bogoliubov - de - gennes equations and the gap functions we find two distinct phases : first, time - reversal symmetry breaking enhances the spin currents but does not lead to chiral supercurrents. a secondary phase transition then triggers a spin magnetization and an orbital supercurrent near the twin boundary.
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arxiv:1302.5610
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purpose : we propose a mathematical framework for quantitative analysis weighting the impact of heterogeneous components of a surgery. while multi - level approaches, surgical process modeling and other workflow analysis methods exist, this is to our knowledge the first quantitative approach. methods : inspired by the group decision making problem from the field of operational research, we define event impact factors, which combine independent and very diverse low - level functions. this allows us to rate surgical events by their importance. results : we conducted surveys with 4 surgeons to determine the importance of roles, phases and their combinations within a laparoscopic cholecystectomy. applying this data on a recorded surgery, we showed that it is possible to define a quantitative measure for deciding on acception or rejection of calls to different roles and at different phases of surgery. conclusions : this methodology allows us to use components such as expertise and role of the surgical staff and other aspects of a given surgery in order to quantitatively analyze and evaluate events, actions, user interfaces or procedures.
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arxiv:1702.00582
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recent developments in nuclear many - body theory enabled the description of open - shell medium - mass nuclei from first principles by exploiting the spontaneous breaking of symmetries within correlation expansion methods. once combined with systematically improvable inter - nucleon interactions consistently derived from chiral effective field theory, modern ab initio nuclear structure calculations provide a powerful framework to deliver first - principle predictions accompanied with theoretical uncertainties. in this letter, controlled ab initio bogoliubov coupled cluster ( bcc ) calculations are performed for the first time, targeting the ground - state of all calcium, nickel and tin isotopes up to mass a ~ 180. while showing good agreement with available experimental data, the shell structure evolution in neutron - rich isotopes and the location of the neutron drip - lines are predicted. the bcc approach constitutes a key development towards reliable first - principles simulations of heavy - mass open - shell nuclei.
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arxiv:2307.15619
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in this paper we report calculations of potential energy curves in the $ 1. 2 a. u. \ le r \ le100 a. u. $ range at multireference configuration interaction ( mrci ) level for doubly excited states of the h $ _ 2 $ molecule. we have focused on the $ q _ 2 $ states which lie between the second and third ionization thresholds of h $ _ 2 ^ + $ molecular ion, i. e., $ ^ 2 \ sigma _ u ^ + $ state in which lie the h ( 2l ) + h ( 2l ' ) dissociation channels. the mrci approach allowed us to successfully identify for the first time the molecular state which dissociates into hydrogen atoms at 2s state. further, generalized oscillator strength as a function of transferred momentum for three doubly excited states is also presented. ( some figures in this article are in colour only in the electronic version )
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arxiv:1503.08679
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we present an exhaustive mathematical analysis of the recently proposed non - poissonian ac - tivity driven ( nopad ) model [ moinet et al. phys. rev. lett., 114 ( 2015 ) ], a temporal network model incorporating the empirically observed bursty nature of social interactions. we focus on the aging effects emerging from the non - poissonian dynamics of link activation, and on their effects on the topological properties of time - integrated networks, such as the degree distribution. analytic expressions for the degree distribution of integrated networks as a function of time are derived, ex - ploring both limits of vanishing and strong aging. we also address the percolation process occurring on these temporal networks, by computing the threshold for the emergence of a giant connected component, highlighting the aging dependence. our analytic predictions are checked by means of extensive numerical simulations of the nopad model.
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arxiv:1606.00593
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we suggest a new method on coloring generalized kneser graphs based on hypergraphs with high discrepancy and small number of edges. the main result is providing a proper coloring of k ( n, n / 2 - t, s ) in ( 4 + o ( 1 ) ) ( s + t ) ^ 2 colors, which is produced by hadamard matrices. also, we show that for colorings by independent set of a natural type, this result is the best possible up to a multiplicative constant. our method extends to kneser hypergraphs as well.
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arxiv:1805.09394
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recently backdoor attack has become an emerging threat to the security of deep neural network ( dnn ) models. to date, most of the existing studies focus on backdoor attack against the uncompressed model ; while the vulnerability of compressed dnns, which are widely used in the practical applications, is little exploited yet. in this paper, we propose to study and develop robust and imperceptible backdoor attack against compact dnn models ( ribac ). by performing systematic analysis and exploration on the important design knobs, we propose a framework that can learn the proper trigger patterns, model parameters and pruning masks in an efficient way. thereby achieving high trigger stealthiness, high attack success rate and high model efficiency simultaneously. extensive evaluations across different datasets, including the test against the state - of - the - art defense mechanisms, demonstrate the high robustness, stealthiness and model efficiency of ribac. code is available at https : / / github. com / huyvnphan / eccv2022 - ribac
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arxiv:2208.10608
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} _ { r, s } ^ n ( q ) $ - bimodule satisfies schur - weyl duality.
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arxiv:0810.1227
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consider an irreducible finite coxeter system. we show that for any nonnegative integer n the sum of the nth powers of the coxeter exponents can be written uniformly as a polynomial in four parameters : h ( the coxeter number ), r ( the rank ), and two further parameters.
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arxiv:1101.5082
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the structure and interface characteristics of ( lavo3 ) 6m ( srvo3 ) m superlattices deposited on ( 100 ) - srtio3 ( sto ) substrate were studied using transmission electron microscopy ( tem ). cross - section tem studies revealed that both lavo3 ( lvo ) and srvo3 ( svo ) layers are good single crystal quality and epitaxially grown with respect to the substrate. it is evidenced that lvo layers are made of two orientational variants of a distorted perovskite compatible with bulk lavo3 while svo layers suffers from a tetragonal distortion due to the substrate induced stain. electron energy loss spectroscopy ( eels ) investigations indicate changes in the fine structure of the v l23 edge, related to a valence change between the lavo3 and srvo3 layers.
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arxiv:1012.3665
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this paper studies the virtual $ \ chi _ { - y } $ - genera of grothendieck ' s quot schemes on surfaces, thus refining the calculations of the virtual euler characteristics by oprea - pandharipande. we first prove a structural result expressing the equivariant virtual $ \ chi _ { - y } $ - genera of quot schemes universally in terms of the seiberg - witten invariants. the formula is simpler for curve classes of seiberg - witten length $ n $, which are defined in the paper. by way of application, we give complete answers in the following cases : ( i ) arbitrary surfaces for the zero curve class, ( ii ) relatively minimal elliptic surfaces for rational multiples of the fiber class, ( iii ) minimal surfaces of general type with $ p _ g > 0 $ for any curve classes. furthermore, a blow up formula is obtained for curve classes of seiberg - witten length $ n $. as a result of these calculations, we prove that the generating series of the virtual $ \ chi _ { - y } $ - genera are given by rational functions for all surfaces with $ p _ g > 0 $, addressing a conjecture of oprea - pandharipande. in addition, we study the reduced $ \ chi _ { - y } $ - genera for $ k3 $ surfaces and primitive curve classes with connections to the kawai - yoshioka formula.
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arxiv:2003.04429
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we follow the scenario of formation of second generation stars in globular clusters by matter processed by hot bottom burning ( hbb ) in massive asymptotic giant branch ( agb ) stars and super agb stars ( sagb ). in the cluster ngc 2419 we assume the presence of an extreme population directly formed from the agb and sagb ejecta, so we can directly compare the yields for a metallicity z = 0. 0003 with the chemical inventory of the cluster ngc 2419. at such a low metallicity, the hbb temperatures ( well above 108k ) allow a very advanced nucleosynthesis. masses of about 6mo deplete mg and synthesize si, going beyond al, so this latter element results only moderately enhanced ; sodium can not be enhanced. the models are consistent with the observations, although the predicted mg depletion is not as strong as in the observed stars. we predict that the oxygen abundance must be depleted by a huge factor in the mg poor stars. the hbb temperatures are close to the region where other p capture reactions on heavier nuclei become possible. we show that high potassium abundance found in mg poor stars can be achieved during hbb, by p captures on the argon nuclei, if the relevant cross section ( s ) are larger than listed in the literature or if the hbb temperature is higher. finally, we speculate that some calcium production is occurring owing to proton capture on potassium. we emphasize the importance of a strong effort to measure a larger sample of abundances in this cluster.
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arxiv:1211.3857
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unsupervised multi - object segmentation has shown impressive results on images by utilizing powerful semantics learned from self - supervised pretraining. an additional modality such as depth or motion is often used to facilitate the segmentation in video sequences. however, the performance improvements observed in synthetic sequences, which rely on the robustness of an additional cue, do not translate to more challenging real - world scenarios. in this paper, we propose the first fully unsupervised method for segmenting multiple objects in real - world sequences. our object - centric learning framework spatially binds objects to slots on each frame and then relates these slots across frames. from these temporally - aware slots, the training objective is to reconstruct the middle frame in a high - level semantic feature space. we propose a masking strategy by dropping a significant portion of tokens in the feature space for efficiency and regularization. additionally, we address over - clustering by merging slots based on similarity. our method can successfully segment multiple instances of complex and high - variety classes in youtube videos.
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arxiv:2310.06907
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we investigate the stability properties and the dynamics of bose - einstein condensates with axial symmetry, especially with dipolar long - range interaction, using both simulations on grids and variational calculations. we present an extended variational ansatz which is applicable for axial symmetry and show that this ansatz can reproduce the lowest eigenfrequencies of the bogoliubov spectrum, and also the corresponding eigenfunctions. our variational ansatz is capable of describing the roton instability of pancake - shaped dipolar condensates for arbitrary angular momenta. after investigating the linear regime we apply the ansatz to determine the dynamics and show how the angular collapse is correctly described within the variational framework.
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arxiv:1212.4006
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we study the causal bandit problem that entails identifying a near - optimal intervention from a specified set $ a $ of ( possibly non - atomic ) interventions over a given causal graph. here, an optimal intervention in $ { a } $ is one that maximizes the expected value for a designated reward variable in the graph, and we use the standard notion of simple regret to quantify near optimality. considering bernoulli random variables and for causal graphs on $ n $ vertices with constant in - degree, prior work has achieved a worst case guarantee of $ \ widetilde { o } ( n / \ sqrt { t } ) $ for simple regret. the current work utilizes the idea of covering interventions ( which are not necessarily contained within $ { a } $ ) and establishes a simple regret guarantee of $ \ widetilde { o } ( \ sqrt { n / t } ) $. notably, and in contrast to prior work, our simple regret bound depends only on explicit parameters of the problem instance. we also go beyond prior work and achieve a simple regret guarantee for causal graphs with unobserved variables. further, we perform experiments to show improvements over baselines in this setting.
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arxiv:2305.04638
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we discuss the possibility of mathieu group m24 acting as symmetry group on the k3 elliptic genus as proposed recently by ooguri, tachikawa and one of the present authors. one way of testing this proposal is to derive the twisted elliptic genera for all conjugacy classes of m24 so that we can determine the unique decomposition of expansion coefficients of k3 elliptic genus into irreducible representations of m24. in this paper we obtain all the hitherto unknown twisted elliptic genera and find a strong evidence of mathieu moonshine.
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arxiv:1008.4924
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we suppose that performance is a random variable whose expectation is related to training inputs, and we study four performance measures in a statistical model that relates performance to training. our aim is to carry out a robust statistical analysis of the training - performance models that are used in proprietary software to plan training, and thereby put them on a firmer footing. the performance measures we consider are calculated using power output and heart rate data collected in the field by road cyclists. we find that parameter estimates in the training - performance models that we study differ across riders and across performance measures within riders. we conclude therefore that models and their estimates must be specific, both to the individual and to the quality ( e. g. speed or endurance ) that the individual seeks to train. while the parameter estimates we obtain may be useful for comparing given training programmes, we show that the underlying models themselves are not appropriate for the optimisation of a training schedule in advance of competition.
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arxiv:1902.02061
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this paper is concerned with the resource allocation in a multi - unmanned aerial vehicle ( uav ) - aided network for providing enhanced mobile broadband ( embb ) services for user equipments. different from most of the existing network resource allocation approaches, we investigate a joint non - orthogonal user association, subchannel allocation and power control problem. the objective of the problem is to maximize the network energy efficiency under the constraints on user equipments ' quality of service, uavs ' network capacity and power consumption. we formulate the energy efficiency maximization problem as a challenging mixed - integer non - convex programming problem. to alleviate this problem, we first decompose the original problem into two subproblems, namely, an integer non - linear user association and subchannel allocation subproblem and a non - convex power control subproblem. we then design a two - stage approximation strategy to handle the non - linearity of the user association and subchannel allocation subproblem and exploit a successive convex approximation approach to tackle the non - convexity of the power control subproblem. based on the derived results, we develop an iterative algorithm with provable convergence to mitigate the original problem. simulation results show that our proposed framework can improve energy efficiency compared with several benchmark algorithms.
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arxiv:1912.03602
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when the initial state evolution of a parton shower is organized according to the standard " backward evolution ' ' prescription, ratios of parton distribution functions appear in the splitting probabilities. the shower thus organized evolves from a hard scale to a soft cutoff scale. at the end of the shower, one expects that only the parton distributions at the soft scale should affect the results. the other effects of the parton distributions should have cancelled. this means that the kernels for parton evolution should be related to the shower splitting functions. if the initial state partons can have non - zero masses, this requires that the evolution kernels cannot be the usual msbar kernels. we work out what the parton evolution kernels should be to match the shower evolution contained in the parton shower event generator deductor, in which the b and c quarks have non - zero masses.
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arxiv:1401.6368
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time series forecasting has important applications across diverse domains. easytime, the system we demonstrate, facilitates easy use of time - series forecasting methods by researchers and practitioners alike. first, easytime enables one - click evaluation, enabling researchers to evaluate new forecasting methods using the suite of diverse time series datasets collected in the preexisting time series forecasting benchmark ( tfb ). this is achieved by leveraging tfb ' s flexible and consistent evaluation pipeline. second, when practitioners must perform forecasting on a new dataset, a nontrivial first step is often to find an appropriate forecasting method. easytime provides an automated ensemble module that combines the promising forecasting methods to yield superior forecasting accuracy compared to individual methods. third, easytime offers a natural language q & a module leveraging large language models. given a question like " which method is best for long term forecasting on time series with strong seasonality? ", easytime converts the question into sql queries on the database of results obtained by tfb and then returns an answer in natural language and charts. by demonstrating easytime, we intend to show how it is possible to simplify the use of time series forecasting and to offer better support for the development of new generations of time series forecasting methods.
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arxiv:2412.17603
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in the recent years, the thermal hall transport has risen as an important diagnosis of the physical properties of the elementary excitations in various quantum materials, especially among the mott insulating systems where the electronic transports are often featureless. here we review the recent development of thermal hall effects in quantum magnets where all the relevant excitations are charge - neutral. in addition to summarizing the existing experiments, we pay a special attention to the underlying mechanisms of the thermal hall effects in various magnetic systems, and clarify the connection between the microscopic physical variables and the emergent degrees of freedom in different quantum phases. the external magnetic field is shown to modify the intrinsic berry curvature properties of various emergent and / or exotic quasiparticle excitations in distinct fashions for different quantum systems and quantum phases, contributing to the thermal hall transports. these include, for example, the conventional ones like the magnons in ordered magnets, the triplons in dimerized magnets, the exotic and fractionalized quasiparticles such as the spinons and the magnetic monopoles in quantum spin liquids. we review their contribution and discuss their presence in the thermal hall conductivity in different physical contexts. we expect this review to provide a useful guidance for the physical mechanism of the thermal hall transports in quantum magnets.
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arxiv:2305.04830
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we consider the problem of recovering a low - rank matrix from its clipped observations. clipping is conceivable in many scientific areas that obstructs statistical analyses. on the other hand, matrix completion ( mc ) methods can recover a low - rank matrix from various information deficits by using the principle of low - rank completion. however, the current theoretical guarantees for low - rank mc do not apply to clipped matrices, as the deficit depends on the underlying values. therefore, the feasibility of clipped matrix completion ( cmc ) is not trivial. in this paper, we first provide a theoretical guarantee for the exact recovery of cmc by using a trace - norm minimization algorithm. furthermore, we propose practical cmc algorithms by extending ordinary mc methods. our extension is to use the squared hinge loss in place of the squared loss for reducing the penalty of over - estimation on clipped entries. we also propose a novel regularization term tailored for cmc. it is a combination of two trace - norm terms, and we theoretically bound the recovery error under the regularization. we demonstrate the effectiveness of the proposed methods through experiments using both synthetic and benchmark data for recommendation systems.
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arxiv:1809.04997
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assuming that the e ( 38 ) boson candidate recently observed at the jinr nuclotron is produced in a bremsstrahlung - like manner and decays only to two photons, its coupling constant to light quarks is estimated to be $ \ sim 10 ^ { - 4 } $.
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arxiv:1208.6530
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since their theoretical prediction by peierls in the 30s, charge density waves ( cdw ) have been one of the most commonly encountered electronic phases in low dimensional metallic systems. the instability mechanism originally proposed combines fermi surface nesting and electron - phonon coupling but is, strictly speaking, only valid in one dimension. in higher dimensions, its relevance is questionable as sharp maxima in the static electronic susceptibility \ chi ( q ) are smeared out, and are, in many cases, unable to account for the periodicity of the observed charge modulations. here, we investigate the quasi twodimensional laagsb2, which exhibits two cdw transitions, by a combination of diffuse xray scattering, inelastic x - ray scattering and ab initio calculations. we demonstrate that the cdw formation is driven by phonons softening. the corresponding kohn anomalies are visualized in 3d through the momentum distribution of the x - ray diffuse scattering intensity. we show that they can be quantitatively accounted for by considering the electronic susceptibility calculated from a dirac - like band, weighted by anisotropic electron - phonon coupling. this remarkable agreement sheds new light on the importance of fermi surface nesting in cdw formation.
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arxiv:2105.05940
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the rise of artificial intelligence ( ai ) offers new opportunities to influence cooperative dynamics with greater applicability and control. in this paper, we examine the impact of third - party bots - - agents that do not directly participate in games but unbiasedly modify the payoffs of normal players engaged in prisoner ' s dilemma interactions - - on the emergence of cooperation. using an evolutionary simulation model, we demonstrate that unbiased bots are unable to shift the defective equilibrium among normal players in well - mixed populations. however, in structured populations, despite their unbiased actions, the bots spontaneously generate distinct impacts on cooperators and defectors, leading to enhanced cooperation. notably, bots that apply negative influences are more effective at promoting cooperation than those applying positive ones, as fewer bots are needed to catalyze cooperative behavior among normal players. however, as the number of bots increases, a trade - off emerges : while cooperation is maintained, overall social payoffs decline. these findings highlight the need for careful management of ai ' s role in social systems, as even well - intentioned bots can have unintended consequences on collective outcomes.
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arxiv:2409.14975
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online petitions are a cost - effective way for citizens to collectively engage with policy - makers in a democracy. predicting the popularity of a petition - - - commonly measured by its signature count - - - based on its textual content has utility for policy - makers as well as those posting the petition. in this work, we model this task using cnn regression with an auxiliary ordinal regression objective. we demonstrate the effectiveness of our proposed approach using uk and us government petition datasets.
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arxiv:1805.06566
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→ f that preserve addition and multiplication and that send elements of e to themselves ). the importance of this group stems from the fundamental theorem of galois theory, which constructs an explicit one - to - one correspondence between the set of subgroups of gal ( f / e ) and the set of intermediate extensions of the extension f / e. by means of this correspondence, group - theoretic properties translate into facts about fields. for example, if the galois group of a galois extension as above is not solvable ( cannot be built from abelian groups ), then the zeros of f cannot be expressed in terms of addition, multiplication, and radicals, i. e., expressions involving n { \ displaystyle { \ sqrt [ { n } ] { ~ } } }. for example, the symmetric groups sn is not solvable for n ≥ 5. consequently, as can be shown, the zeros of the following polynomials are not expressible by sums, products, and radicals. for the latter polynomial, this fact is known as the abel – ruffini theorem : f ( x ) = x5 − 4x + 2 ( and e = q ), f ( x ) = xn + an−1xn−1 + + a0 ( where f is regarded as a polynomial in e ( a0,..., an−1 ), for some indeterminates ai, e is any field, and n ≥ 5 ). the tensor product of fields is not usually a field. for example, a finite extension f / e of degree n is a galois extension if and only if there is an isomorphism of f - algebras f ⊗e f fn. this fact is the beginning of grothendieck ' s galois theory, a far - reaching extension of galois theory applicable to algebro - geometric objects. = = invariants of fields = = basic invariants of a field f include the characteristic and the transcendence degree of f over its prime field. the latter is defined as the maximal number of elements in f that are algebraically independent over the prime field. two algebraically closed fields e and f are isomorphic precisely if these two data agree. this implies that any two uncountable algebraically closed fields of the same cardinality and the same characteristic are isomorphic. for example, qp, cp and c are isomorphic ( but not isomorphic as topological fields ). = = = model theory of fields
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https://en.wikipedia.org/wiki/Field_(mathematics)
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on the unit tangent bundle of a compact riemannian surface of constant nonzero curvature, we study semiclassical schr { \ " o } dinger operators associated with the natural sub - riemannian laplacian built along the horizontal bundle. in that setup, the involved reeb flow is periodic and we show that high - frequency schr { \ " o } dinger eigenfunctions enjoy extra regularity properties. as an application, we derive regularity properties for low - energy eigenmodes of semiclassical magnetic schr { \ " o } dinger operators on the underlying surface by considering joint eigenfunctions with the reeb vector field.
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arxiv:2311.02990
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in the effective mass approximation for electronic ( hole ) states of a spheroidal quantum dot with and without external fields the perturbation theory schemes are constructed in the framework of the kantorovich and adiabatic methods. the eigenvalues and eigenfunctions of the problem, obtained in both analytical and numerical forms, were applied for the analysis of spectral and optical characteristics of spheroidal quantum dots in homogeneous electric fields.
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arxiv:1211.4768
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characteristic functions of several popular classes of distributions and processes admit analytic continuation into unions of strips and open coni around $ \ mathbb { r } \ subset \ mathbb { c } $. the fourier transform techniques reduces calculation of probability distributions and option prices to evaluation of integrals whose integrands are analytic in domains enjoying these properties. in the paper, we suggest to use changes of variables of the form $ \ xi = \ sqrt { - 1 } \ omega _ 1 + b \ sinh ( \ sqrt { - 1 } \ omega + y ) $ and the simplified trapezoid rule to evaluate the integrals accurately and fast. we formulate the general scheme, and apply the scheme for calculation probability distributions and pricing european options in l \ ' evy models, the heston model, the cir model, and a l \ ' evy model with the cir - subordinator. we outline applications to fast and accurate calibration procedures and monte carlo simulations in l \ ' evy models, regime switching l \ ' evy models that can account for stochastic drift, volatility and skewness, and the heston model. for calculation of quantiles in the tails using the newton or bisection method, it suffices to precalculate several hundred of values of the characteristic exponent at points of an appropriate grid ( { \ em conformal principal components } ) and use these values in formulas for cpdf and pdf.
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arxiv:1808.05295
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much of the data being created on the web contains interactions between users and items. stochastic blockmodels, and other methods for community detection and clustering of bipartite graphs, can infer latent user communities and latent item clusters from this interaction data. these methods, however, typically ignore the items ' contents and the information they provide about item clusters, despite the tendency of items in the same latent cluster to share commonalities in content. we introduce content - augmented stochastic blockmodels ( casb ), which use item content together with user - item interaction data to enhance the user communities and item clusters learned. comparisons to several state - of - the - art benchmark methods, on datasets arising from scientists interacting with scientific articles, show that content - augmented stochastic blockmodels provide highly accurate clusters with respect to metrics representative of the underlying community structure.
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arxiv:1505.06538
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observations of anomalies in the electron - positron angular correlations in high - energy decays in $ ^ 4 $ he, $ ^ 8 $ be, and $ ^ { 12 } $ c have been reported recently by the atomki collaboration. these could be explained by the creation and subsequent decay of a new boson with a mass of $ { \ sim } 17 $ mev. theoretical understanding of pair creation in the proton capture reactions used in these experiments is important for the interpretation of the anomalies. we apply the ab initio no - core shell model with continuum ( ncsmc ) to the proton capture on $ ^ 7 $ li. the ncsmc describes both bound and unbound states in light nuclei in a unified way with chiral two - and three - nucleon interactions as the only input. we investigate the structure of $ ^ 8 $ be, the $ p + ^ 7 $ li elastic scattering, the $ ^ 7 $ li ( $ p, \ gamma $ ) $ ^ 8 $ be cross section and the internal pair creation $ ^ 7 $ li ( $ p, e ^ + e ^ - $ ) $ ^ 8 $ be. we discuss the impact of a proper treatment of the initial scattering state on the electron - positron angular correlation spectrum and compare our results to available atomki data sets. finally, we calculate $ ^ 7 $ li ( $ p, x $ ) $ ^ 8 $ be cross sections for several proposed models of the hypothetical x17 particle.
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arxiv:2308.13751
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to harness the potential of noisy intermediate - scale quantum devices, it is paramount to find the best type of circuits to run hybrid quantum - classical algorithms. key candidates are parametrized quantum circuits that can be effectively implemented on current devices. here, we evaluate the capacity and trainability of these circuits using the geometric structure of the parameter space via the effective quantum dimension, which reveals the expressive power of circuits in general as well as of particular initialization strategies. we assess the expressive power of various popular circuit types and find striking differences depending on the type of entangling gates used. particular circuits are characterized by scaling laws in their expressiveness. we identify a transition in the quantum geometry of the parameter space, which leads to a decay of the quantum natural gradient for deep circuits. for shallow circuits, the quantum natural gradient can be orders of magnitude larger in value compared to the regular gradient ; however, both of them can suffer from vanishing gradients. by tuning a fixed set of circuit parameters to randomized ones, we find a region where the circuit is expressive, but does not suffer from barren plateaus, hinting at a good way to initialize circuits. we show an algorithm that prunes redundant parameters of a circuit without affecting its effective dimension. our results enhance the understanding of parametrized quantum circuits and can be immediately applied to improve variational quantum algorithms.
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arxiv:2102.01659
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we show that $ k ( 2 ) $ - locally, the smash product of the string bordism spectrum and the spectrum $ t _ 2 $ splits into copies of morava $ e $ - theories. here, $ t _ 2 $ is related to the thom spectrum of the canonical bundle over $ \ omega su ( 4 ) $.
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arxiv:1710.03427
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when the mass of one of the two bodies tends to zero, weyl ' s definition of the gravitational force in an axially symmetric, static two - body solution can be given an invariant formulation in terms of a force four - vector. the norm of this force is calculated for bach ' s two - body solution, that is known to be in one - to - one correspondence with schwarzschild ' s original solution when one of the two masses l, l ' is made to vanish. in the limit when, say, l ' goes to zero, the norm of the force divided by l ' and calculated at the position of the vanishing mass is found to coincide with the norm of the acceleration of a test body kept at rest in schwarzschild ' s field. both norms happen thus to grow without limit when the test body ( respectively the vanishing mass l ' ) is kept at rest in a position closer and closer to schwarzschild ' s two - surface.
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arxiv:gr-qc/0104035
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in this work we compute the rates and numbers of different types of stars and phenomena ( supernovae, novae, white dwarfs, merging neutron stars, black holes ) that contributed to the chemical composition of the solar system. this process is called " chemical evolution ". in particular, we analyse the death rates of stars of all masses, dying either quiescently or explosively. these rates and total star numbers are computed in the context of a revised version of the two - infall model for the chemical evolution of the milky way, which reproduces fairly well the observed abundance patterns of several chemical species, the global solar metallicity, and the current gas, stellar, and total surface mass densities. we compute also the total number of stars ever born and still alive as well as the number of stars born up to the formation of the solar system with a mass and metallicity like the sun. this latter number will account for all the possible existing solar systems which can host life in the solar vicinity. we conclude that, among all the stars ( from 0. 8 to 100 m $ _ { \ odot } $ ) born and died from the beginning up to the solar system formation epoch, which contributed to its chemical composition, 93. 00 \ % are represented by stars dying as single white dwarfs ( without interacting significantly with a companion star ) and originating in the mass range 0. 8 - 8 m $ _ { \ odot } $, while 5. 24 $ \ % $ are neutron stars and 0. 73 $ \ % $ are black holes, both originating from supernovae core - collapse ( m > 8 m $ _ { \ odot } $ ) ; 0. 64 $ \ % $ are type ia supernovae and 0. 40 $ \ % $ are nova systems, both originating from the same mass range as the white dwarfs. the number of stars similar to the sun born from the beginning up to the solar system formation, with metallicity in the range 12 + log ( fe / h ) = 7. 50 $ \ pm $ 0. 04 dex is $ \ sim 31 \ cdot $ 10 $ ^ { 7 } $, and in particular our sun is the $ \ sim 2. 61 \ cdot $ 10 $ ^ 7 $ - th star of this kind.
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arxiv:2406.08036
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we give a detailed proof of the conjecture by hohm and zwiebach in double field theory. this result implies that their proposal for large gauge transformations in terms of the jacobian matrix for coordinate transformations is, as required, equivalent to the standard exponential map associated with the generalized lie derivative along a suitable parameter.
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arxiv:1504.05913
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photon - pair direct or jet - associated productions are important for relevant standard model measurement, higgs and new physics searches at the lhc. the loop - induced gluon - fusion process gg - > \ gamma \ gamma g, which although formally contributes only at the next - to - next - to - leading order to \ gamma \ gamma j productions, may get enhanced by the large gluon flux at the lhc. we have checked and confirmed previous results on gg - > \ gamma \ gamma, \ gamma \ gamma g at one loop, using now the traditional feynman diagram based approach and taking into account the quark mass effects, and further updated them for the 7 and 14 tev lhc with new inputs and settings. we provide the details and results of the calculations, which involves manipulation of rank - 5 pentagon integrals. our results show that the gluon - fusion process can contribute about 10 % of the born result, especially at small m _ { \ gamma \ gamma } and pt _ { \ gamma \ gamma }, and increase further the overall scale uncertainty. top quark loop effects are examined in detail, which shows importance near or above the threshold m _ { \ gamma \ gamma } \ gsim 2m _ t.
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arxiv:1111.0895
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let $ x $ be a centered random variable with unit variance, zero third moment, and such that $ e [ x ^ 4 ] \ ge 3 $. let $ \ { f _ n : n \ geq 1 \ } $ denote a normalized sequence of homogeneous sums of fixed degree $ d \ geq 2 $, built from independent copies of $ x $. under these minimal conditions, we prove that $ f _ n $ converges in distribution to a standard gaussian random variable if and only if the corresponding sequence of fourth moments converges to $ 3 $. the statement is then extended ( mutatis mutandis ) to the free probability setting. we shall also discuss the optimality of our conditions in terms of explicit thresholds, as well as establish several connections with the so - called universality phenomenon of probability theory. both in the classical and free probability frameworks, our results extend and unify previous fourth moment theorems for gaussian and semicircular approximations. our techniques are based on a fine combinatorial analysis of higher moments for homogeneous sums.
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arxiv:1407.6216
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we exhibit a one to one correspondence between some universal probabilistic properties of the ordering coordinate of one - dimensional ising - like models and a class of continuous time random walks. this correspondence provides an new qualitative picture of the properties of the ordering coordinate of the ising model.
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arxiv:cond-mat/9810378
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times 320 $ was obtained by a 2d cnn in $ 3. 5 \ pm 0. 2 $ s.
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arxiv:2012.03014
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the electric dipole strength in 120sn has been extracted from proton inelastic scattering experiments at e _ p = 295 mev and at forward angles including 0 degree. below neutron threshoild it differs from the results of a 120sn ( gamma, gamma ' ) experiment and peaks at an excitation energy of 8. 3 mev. the total strength corresponds to 2. 3 ( 2 ) % of the energy - weighted sum rule and is more than three times larger than what is observed with the ( gamma, gamma ' ) reaction. this implies a strong fragmentation of the e1 strength and / or small ground state branching ratios of the excited 1 - states.
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arxiv:1502.04305
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if a pure state of a qubit pair is developed over the four basis states, it is known that an equality between the four coefficients of that development exists if and only if that state is unentangled. this paper considers an arbitrary pure state of an n - qubit system, developed over the 2 ^ n basis states. it is shown that the state is unentangled if and only if a well - chosen collection of ( 2 ^ n - ( n + 1 ) ) equalities between the 2 ^ n coefficients of that development is verified. the number of these equalities is large a soon as n = 10, but it is shown that this set of equalities may be classified into ( n - 1 ) subsets, which should facilitate their manipulation. this result should be useful e. g. in the contexts of blind quantum source separation ( bqss ) and blind quantum process tomography ( bqpt ), with an aim which should not be confused with that found when using the concept of equivalence of pure states through local unitary transformations.
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arxiv:1902.10417
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we discuss the non - perturbative aspect of zero dimensional superstring. the perturbative expansions of correlation functions diverge as $ \ sum _ l ( 3l )! \ kappa ^ { 2l } $, where $ \ kappa $ is a string coupling constant. this implies there are non - perturbative contributions of order $ \ e ^ { c \ kappa ^ { - { 2 \ over 3 } } } $. ( here $ c $ is a constant. ) this situation contrasts with those of critical or non - critical bosonic strings, where the perturbative expansions diverge as $ \ sum _ ll! \ kappa ^ { 2l } $ and non - perturbative behaviors go as $ \ e ^ { c \ kappa ^ { - 1 } } $. it is explained how such nonperturbative effects of order $ \ e ^ { c \ kappa ^ { - { 2 \ over 3 } } } $ appear in zero dimensional superstring theory. due to these non - perturbative effects, the supersymmetry in target space breaks down spontaneously.
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arxiv:hep-th/9112003
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internet technology is so pervasive today, for example, from online social networking to online banking, it has made people ' s lives more comfortable. due the growth of internet technology, security threats to systems and networks are relentlessly inventive. one such a serious threat is " phishing ", in which, attackers attempt to steal the user ' s credentials using fake emails or websites or both. it is true that both industry and academia are working hard to develop solutions to combat against phishing threats. it is therefore very important that organisations to pay attention to end - user awareness in phishing threat prevention. therefore, the aim of our paper is twofold. first, we will discuss the history of phishing attacks and the attackers ' motivation in details. then, we will provide taxonomy of various types of phishing attacks. second, we will provide taxonomy of various solutions proposed in literature to protect users from phishing based on the attacks identified in our taxonomy. moreover, we have also discussed impact of phishing attacks in internet of things ( iots ). we conclude our paper discussing various issues and challenges that still exist in the literature, which are important to fight against with phishing threats.
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arxiv:1705.09819
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the advent of deep learning has introduced efficient approaches for de novo protein sequence design, significantly improving success rates and reducing development costs compared to computational or experimental methods. however, existing methods face challenges in generating proteins with diverse lengths and shapes while maintaining key structural features. to address these challenges, we introduce cpdiffusion - ss, a latent graph diffusion model that generates protein sequences based on coarse - grained secondary structural information. cpdiffusion - ss offers greater flexibility in producing a variety of novel amino acid sequences while preserving overall structural constraints, thus enhancing the reliability and diversity of generated proteins. experimental analyses demonstrate the significant superiority of the proposed method in producing diverse and novel sequences, with cpdiffusion - ss surpassing popular baseline methods on open benchmarks across various quantitative measurements. furthermore, we provide a series of case studies to highlight the biological significance of the generation performance by the proposed method. the source code is publicly available at https : / / github. com / riacd / cpdiffusion - ss
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arxiv:2407.07443
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we employ the familiar canonical quantization procedure in a given cosmological setting to argue that it is equivalent to and results in the same physical picture if one considers the deformation of the phase - space instead. to show this we use a probabilistic evolutionary process ( pep ) to make the solutions of these different approaches comparable. specific model theories are used to show that the independent solutions of the resulting wheeler - dewitt equation are equivalent to solutions of the deformation method with different signs for the deformation parameter. we also argued that since the wheeler - dewitt equation is a direct consequence of diffeomorphism invariance, this equivalence is only true provided that the deformation of phase - space does not break such an invariance.
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arxiv:0909.2487
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the casimir force between two parallel uncharged closely spaced metallic plates is evaluated in ways alternatives to those usually considered in the literature. in a first approximation we take in account the suppressed quantum numbers of a cubic box, representing a cavity which was cut in a metallic block. we combine these ideas with those of the mit bag model of hadrons, but adapted to non - relativistic particles. in a second approximation we consider the particles occupying the energy levels of the bohr atom, so that the casimir force depends explicitly on the fine structure constant alpha. in both treatments, the mean energies which have explicit dependence on the particle mass and on the maximum occupied quantum number ( related to the fermi level of the system ) at the beginning of the calculations, have these dependences mutually canceled at the end of them. finally by comparing the averaged energies computed in both approximations, we are able to make an estimate of the value of the fine structure constant alpha.
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arxiv:0901.0908
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we show a duality of branes in the topological b - model by inserting two kinds of the non - compact branes simultaneously. we explicitly derive the integral formula for the matrix model partition function describing this situation, which correspondingly includes both of the characteristic polynomial and the external source. we show that these two descriptions are dual to each other through the fourier transformation, and the brane partition function satisfies integrable equations in one and two dimensions.
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arxiv:1401.0956
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the monitoring of quiescent emission from neutron star transients with accretion outbursts long enough to significantly heat the neutron star crust has opened a new vista onto the physics of dense matter. in this paper we construct models of the thermal relaxation of the neutron star crust following the end of a protracted accretion outburst. we confirm the finding of shternin et al., that the thermal conductivity of the neutron star crust is high, consistent with a low impurity parameter. we describe the basic physics that sets the broken power - law form of the cooling lightcurve. the initial power law decay gives a direct measure of the temperature profile, and hence the thermal flux during outburst, in the outer crust. the time of the break, at hundreds of days post - outburst, corresponds to the thermal time where the solid transitions from a classical to quantum crystal, close to neutron drip. we calculate in detail the constraints on the crust parameters of both ks 1731 - 260 and mxb 1659 - 29 from fitting their cooling lightcurves. our fits to the lightcurves require that the neutrons do not contribute significantly to the heat capacity in the inner crust, and provide evidence in favor of the existence of a neutron superfluid throughout the inner crust. our fits to both sources indicate an impurity parameter of order unity in the inner crust.
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arxiv:0901.3115
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in real - world regression tasks, datasets frequently exhibit imbalanced distributions, characterized by a scarcity of data in high - complexity regions and an abundance in low - complexity areas. this imbalance presents significant challenges for existing classification methods with clear class boundaries, while highlighting a scarcity of approaches specifically designed for imbalanced regression problems. to better address these issues, we introduce a novel concept of imbalanced regression, which takes into account both the complexity of the problem and the density of data points, extending beyond traditional definitions that focus only on data density. furthermore, we propose error distribution smoothing ( eds ) as a solution to tackle imbalanced regression, effectively selecting a representative subset from the dataset to reduce redundancy while maintaining balance and representativeness. through several experiments, eds has shown its effectiveness, and the related code and dataset can be accessed at https : / / anonymous. 4open. science / r / error - distribution - smoothing - 762f.
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arxiv:2502.02277
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transit timing variations, or ttvs, can be a very efficient way of constraining masses and eccentricities of multi - planet systems. recent measurements of the ttvs of trappist - 1 led to an estimate of the masses of the planets, enabling an estimate of their densities. a recent ttv analysis using data obtained in the past two years yields a 34 % and 13 % increase in mass for trappist - 1b and c, respectively. in most studies to date, a newtonian n - body model is used to fit the masses of the planets, while sometimes general relativity is accounted for. using the posidonius n - body code, we show that in the case of the trappist - 1 system, non - newtonian effects might be also relevant to correctly model the dynamics of the system and the resulting ttvs. in particular, using standard values of the tidal love number $ k _ 2 $ ( accounting for the tidal deformation ) and the fluid love number $ k _ { 2f } $ ( accounting for the rotational flattening ) leads to differences in the ttvs of trappist - 1b and c similar to the differences caused by general relativity. we also show that relaxing the values of tidal love number $ k _ 2 $ and the fluid love number $ k _ { 2f } $ can lead to ttvs which differ by as much as a few 10 ~ s on a $ 3 - 4 $ - year timescale, which is a potentially observable level. the high values of the love numbers needed to reach observable levels for the ttvs could be achieved for planets with a liquid ocean, which, if detected, might then be interpreted as a sign that trappist - 1b and trappist - 1c could have a liquid magma ocean. for trappist - 1 and similar systems, the models to fit the ttvs should potentially account for general relativity, for the tidal deformation of the planets, for the rotational deformation of the planets and, to a lesser extent, for the rotational deformation of the star, which would add up to 7x2 + 1 = 15 additional free parameters in the case of trappist - 1.
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arxiv:2002.02015
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undecidability of various properties of first order term rewriting systems is well - known. an undecidable property can be classified by the complexity of the formula defining it. this gives rise to a hierarchy of distinct levels of undecidability, starting from the arithmetical hierarchy classifying properties using first order arithmetical formulas and continuing into the analytic hierarchy, where also quantification over function variables is allowed. in this paper we consider properties of first order term rewriting systems and classify them in this hierarchy. weak and strong normalization for single terms turn out to be sigma - 0 - 1 - complete, while their uniform versions as well as dependency pair problems with minimality flag are pi - 0 - 2 - complete. we find that confluence is pi - 0 - 2 - complete both for single terms and uniform. unexpectedly weak confluence for ground terms turns out to be harder than weak confluence for open terms. the former property is pi - 0 - 2 - complete while the latter is sigma - 0 - 1 - complete ( and thereby recursively enumerable ). the most surprising result is on dependency pair problems without minimality flag : we prove this to be pi - 1 - 1 - complete, which means that this property exceeds the arithmetical hierarchy and is essentially analytic.
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arxiv:0902.4723
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hd 326823 is a peculiar emission line object. in the literature it was considered as a pre - wn candidate. based mainly on high resolution data, obtained with the feros spectrograph, we made an atlas covering 3800 - 9200a region. this atlas confirms the presence of several strong hei lines and numerous n lines. there is also a deficiency of h, indicating that this object is indeed in an evolved stage. in addition, with low resolution spectra, we obtained intensities of several lines.
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arxiv:astro-ph/0109039
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the anomaly against the gaussianity in the wmap data was alleged to be due to insufficient handling of beam asymmetries. in this paper we investigate this issue and develop a method to estimate the shape of the inflight effective beam, particularly the asymmetry and azimuthal orientation. we divide the whole map into square patches and exploit the information in the fourier space. for patches containing bright extra - galactic point sources, we can directly estimate their shapes, from which the inflight effective beam manifests itself. for those without, we estimate the pattern via perturbing the phases and directly from the fourier amplitudes. we show that the inflight effective beam convolving the signal is indeed non - symmetric for most part of the sky, and it ' s not randomly oriented. around the ecliptic poles, however, the asymmetry is smaller due to the averaging effect from different orientations of the beam from the scan strategy. the effective beam with significant asymmetry is combing with almost parallel fashion along the lines of ecliptic longitude. in the foreground - cleaned ilc map, however, the systematics caused by beam effect is significantly lessened.
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arxiv:1309.0583
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generative text - to - image models, such as stable diffusion, have demonstrated a remarkable ability to generate diverse, high - quality images. however, they are surprisingly inept when it comes to rendering human hands, which are often anatomically incorrect or reside in the " uncanny valley ". in this paper, we propose a method handcraft for restoring such malformed hands. this is achieved by automatically constructing masks and depth images for hands as conditioning signals using a parametric model, allowing a diffusion - based image editor to fix the hand ' s anatomy and adjust its pose while seamlessly integrating the changes into the original image, preserving pose, color, and style. our plug - and - play hand restoration solution is compatible with existing pretrained diffusion models, and the restoration process facilitates adoption by eschewing any fine - tuning or training requirements for the diffusion models. we also contribute malhand datasets that contain generated images with a wide variety of malformed hands in several styles for hand detector training and hand restoration benchmarking, and demonstrate through qualitative and quantitative evaluation that handcraft not only restores anatomical correctness but also maintains the integrity of the overall image.
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arxiv:2411.04332
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we consider the dilaton gravity models derived by reductions of generalized theories of gravity and study one - dimensional dynamical systems simultaneously describing cosmological and static states in any gauge. our approach is fully applicable to studying static and cosmological solutions in multidimensional theories and also in general one - dimensional dilaton - scalaron gravity models. we here focus on general and global properties of the models, on seeking integrals, and on analyzing the structure of the solution space. we propose some new ideas in this direction and derive new classes of integrals and new integrable models.
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arxiv:1403.6815
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split rank of a rational polyhedron is finite. the well known proof of this is based on the fact that split closure is stronger than the chv \ ' { a } tal closure, and the chv \ ' { a } tal rank of a rational polyhedron is finite due to the result of chv \ ' { a } tal and schrijver. in this note we provide an independent proof for the fact that every rational polyhedron has finite split rank. in principal, we construct a nonnegative potential function which decreases by at least one with " every " second split closure unless the integer hull of the polyhedron is reached.
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arxiv:1606.05811
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there are 10 generalized kac - moody algebras whose denominator identities are completely reflective automorphic products of singular weight on lattices of squarefree level. under the assumption that the meromorphic vertex operator algebra of central charge 24 and spin - 1 algebra $ \ hat { a } _ { p - 1, p } ^ r $ exists we show that four of them can be constructed in a uniform way from bosonic strings moving on suitable target spaces.
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arxiv:0801.1829
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power sector decarbonization plays a vital role in the upcoming energy transition towards a more sustainable future. decentralized energy resources, such as electric vehicles ( ev ) and solar photovoltaic systems ( pv ), are continuously integrated in residential power systems, increasing the risk of bottlenecks in power distribution networks. this paper aims to address the challenge of domestic ev charging while prioritizing clean, solar energy consumption. real time - of - use tariffs are treated as a price - based demand response ( dr ) mechanism that can incentivize end - users to optimally shift ev charging load in hours of high solar pv generation with the use of deep reinforcement learning ( drl ). historical measurements from the pecan street dataset are analyzed to shape a flexibility potential reward to describe end - user charging preferences. experimental results show that the proposed dqn ev optimal charging policy is able to reduce electricity bills by an average 11. 5 \ % by achieving an average utilization of solar power 88. 4
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arxiv:2211.09479
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we study the problem of reconstruction of high - energy cosmic rays mass composition from the experimental data of extensive air showers. we develop several machine learning methods for the reconstruction of energy spectra of separate primary nuclei at energies 1 - 100 pev, using the public data and monte - carlo simulations of the kascade experiment from the kcdc platform. we estimate the uncertainties of our methods, including the unfolding procedure, and show that the overall accuracy exceeds that of the method used in the original studies of the kascade experiment.
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arxiv:2311.06893
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we explore the physical implications of applying principal component analysis ( pca ) to translationally invariant classical systems defined on a $ d $ - dimensional hypercubic lattice. using rayleigh - schr \ " odinger perturbation theory, we demonstrate that the principal components are related to the reciprocal lattice vectors of the hypercubic lattice, and the corresponding eigenvalues are connected to the discrete fourier transform of the sampled configurations. from a different perspective, we show that the pca in question can be viewed as a numerical method for computing the ensemble average of the squared moduli of the fourier transform of physical quantities. our results also provide a way to determine approximately the principal components of a classical system with translational invariance without the need for matrix diagonalization.
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arxiv:2410.22682
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on - shell methods offer an alternative definition of quantum field theory at tree - level, replacing feynman diagrams with recursion relations and interaction vertices with a handful of seed scattering amplitudes. in this paper we determine the simplest recursion relations needed to construct a general four - dimensional quantum field theory of massless particles. for this purpose we define a covering space of recursion relations which naturally generalizes all existing constructions, including those of bcfw and risager. the validity of each recursion relation hinges on the large momentum behavior of an n - point scattering amplitude under an m - line momentum shift, which we determine solely from dimensional analysis, lorentz invariance, and locality. we show that all amplitudes in a renormalizable theory are 5 - line constructible. amplitudes are 3 - line constructible if an external particle carries spin or if the scalars in the theory carry equal charge under a global or gauge symmetry. remarkably, this implies the 3 - line constructibility of all gauge theories with fermions and complex scalars in arbitrary representations, all supersymmetric theories, and the standard model. moreover, all amplitudes in non - renormalizable theories without derivative interactions are constructible ; with derivative interactions, a subset of amplitudes is constructible. we illustrate our results with examples from both renormalizable and non - renormalizable theories. our study demonstrates both the power and limitations of recursion relations as a self - contained formulation of quantum field theory.
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arxiv:1502.05057
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awale games have become widely recognized across the world, for their innovative strategies and techniques which were used in evolving the agents ( player ) and have produced interesting results under various conditions. this paper will compare the results of the two major machine learning techniques by reviewing their performance when using minimax, endgame database, a combination of both techniques or other techniques, and will determine which are the best techniques.
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arxiv:1309.1543
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we investigate topological phases of monolayer jacutingaite ( pt $ _ 2 $ hgse $ _ 3 $ ) that arise when considering the competing effects of spin - orbit coupling ( soc ), magnetic exchange interactions, and staggered sublattice potential v. the interplay between the staggered potential and exchange field offers the possibility of attaining different topological phases. by analyzing the berry curvatures and computing the chern numbers and hall conductivities, we demonstrate that the system is time - reversal - symmetry - broken quantum spin hall insulator when $ m _ b < \ lambda _ { so } $, where $ m _ b $ is the exchange field operating on the bottom hg sublattice and $ \ lambda _ { so } $ is the intrinsic soc. for $ m _ b > \ lambda _ { so } $ and in the presence of rashba soc, we find that the band gap at valley $ k ( k ^ { \ prime } ) $ is topologically trivial ( non - trivial ) with chern number $ c = 1 $ and valley chern number $ c _ v = - 1 $, indicating that the system is valley - polarized quantum anomalous hall insulator. we show that the topology of each valley is swapped ( the chern number becomes $ c = - 1 $ ) by reversing the sign of the exchange field. the system transitions to a valley - polarized metal and quantum valley hall phase as v increases. along the phase boundaries, we observe a single - dirac cone semimetal states. these findings shed more light on the possibility of realizing and controlling topological phases in spintronics and valleytronics devices.
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arxiv:2212.10667
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in the presented paper production of charmonium state $ \ mathcal { q } $ in exclusive $ w \ to \ mathcal { q } d _ { s } ^ { ( * ) } $ decays is analyzed in the framework of both leading order nonrelativistic quantum chromodynamics ( nrqcd ) and light - cone expansion ( lc ) models. analytical and numerical predictions for the branching fractions of these decays in both approaches are given. the typical value of the branching fractions is $ \ sim 10 ^ { - 11 } $ and it turns out the lc results are about 4 times lager than nrqcd ones, so the effect of internal quark should be taken into account. some estimates of color - octet contributions are presented and it is shown, that these contributions could be comparable with color - singlet results.
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arxiv:1801.08998
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in recent years, there has been significant interest in creating 3d avatars and motions, driven by their diverse applications in areas like film - making, video games, ar / vr, and human - robot interaction. however, current efforts primarily concentrate on either generating the 3d avatar mesh alone or producing motion sequences, with integrating these two aspects proving to be a persistent challenge. additionally, while avatar and motion generation predominantly target humans, extending these techniques to animals remains a significant challenge due to inadequate training data and methods. to bridge these gaps, our paper presents three key contributions. firstly, we proposed a novel agent - based approach named motion avatar, which allows for the automatic generation of high - quality customizable human and animal avatars with motions through text queries. the method significantly advanced the progress in dynamic 3d character generation. secondly, we introduced a llm planner that coordinates both motion and avatar generation, which transforms a discriminative planning into a customizable q & a fashion. lastly, we presented an animal motion dataset named zoo - 300k, comprising approximately 300, 000 text - motion pairs across 65 animal categories and its building pipeline zoogen, which serves as a valuable resource for the community. see project website https : / / steve - zeyu - zhang. github. io / motionavatar /
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arxiv:2405.11286
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phoebe 2 is a python package for modeling the observables of eclipsing star systems, but until now has focused entirely on the forward - model - - that is, generating a synthetic model given fixed values of a large number of parameters describing the system and the observations. the inverse problem, obtaining orbital and stellar parameters given observational data, is more complicated and computationally expensive as it requires generating a large set of forward - models to determine which set of parameters and uncertainties best represent the available observational data. the process of determining the best solution and also of obtaining reliable and robust uncertainties on those parameters often requires the use of multiple algorithms, including both optimizers and samplers. furthermore, the forward - model of phoebe has been designed to be as physically robust as possible, but is computationally expensive compared to other codes. it is useful, therefore, to use whichever code is most efficient given the reasonable assumptions for a specific system, but learning the intricacies of multiple codes presents a barrier to doing this in practice. here we present the 2. 3 release of phoebe ( publicly available from http : / / phoebe - project. org ) which introduces a general framework for defining and handling distributions on parameters, and utilizing multiple different estimation, optimization, and sampling algorithms. the presented framework supports multiple forward - models, including the robust model built into phoebe itself.
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arxiv:2006.16951
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the giant impact hypothesis for moon formation successfully explains the dynamic properties of the earth - moon system but remains challenged by the similarity of isotopic fingerprints of the terrestrial and lunar mantles. moreover, recent geochemical evidence suggests that the earth ' s mantle preserves ancient ( or " primordial " ) heterogeneity that predates the moon - forming giant impact. using a new hydrodynamical method, we here show that moon - forming giant impacts lead to a stratified starting condition for the evolution of the terrestrial mantle. the upper layer of the earth is compositionally similar to the disk, out of which the moon evolves, whereas the lower layer preserves proto - earth characteristics. as long as this predicted compositional stratification can at least partially be preserved over the subsequent billions of years of earth mantle convection, the compositional similarity between the moon and the accessible earth ' s mantle is a natural outcome of realistic and high - probability moon - forming impact scenarios. the preservation of primordial heterogeneity in the modern earth not only reconciles geochemical constraints but is also consistent with recent geophysical observations. furthermore, for significant preservation of a proto - earth reservoir, the bulk composition of the earth - moon system may be systematically shifted towards chondritic values.
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arxiv:1904.02407
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we present calculations of the size distribution of instantons in the 2d o ( 3 ) non - linear sigma - model, and briefly discuss the effects cooling has upon the configurations and the topological objects. ( this preprint is also available via anonymous ftp to suna. amtp. liv. ac. uk in / pub / pss / as instdist. uue. )
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arxiv:hep-lat/9404001
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the $ dd ^ * $ scattering phase shifts in the $ t _ { cc } ^ + = cc \ bar { u } \ bar { d } $ channel are extracted from lattice qcd for five different charm quark masses and a fixed light - quark mass corresponding to $ m _ \ pi \ simeq 280 $ ~ mev. the phase shifts are analysed employing two approaches : effective range expansion and lippmann - - schwinger equation derived in the effective field theory. in the latter case, the results imply an attraction at short range parametrised by contact terms and a slight repulsion at long range mediated by one - pion exchange with $ m _ \ pi > m _ { d ^ * } - m _ d $. the poles in the amplitude across the complex energy plane are extracted and their trajectories are discussed as the charm quark mass is varied. two complex conjugate poles corresponding to a resonance below threshold are found for $ m _ c $ close to the physical value. they turn into a pair of virtual states at the largest $ m _ c $ studied. with further increasing $ m _ c $, one virtual pole representing $ t _ { cc } ^ + $ is expected to move towards the two - body threshold and turn into a bound state. the light - quark mass dependence of the $ t _ { cc } ^ + $ pole is briefly discussed using the data on $ dd ^ * $ scattering from other lattice collaborations.
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arxiv:2402.14715
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