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formation of fermion bag solitons is an important paradigm in the theory of hadron structure. we study this phenomenon non - perturbatively in the 1 + 1 dimensional massive gross - neveu model, in the large $ n $ limit. we find, applying inverse scattering techniques, that the extremal static bag configurations are reflectionless, as in the massless gross - neveu model. this adds to existing results of variational calculations, which used reflectionless bag profiles as trial configurations. only reflectionless trial configurations which support a single pair of charge - conjugate bound states of the associated dirac equation were used in those calculations, whereas the results in the present paper hold for bag configurations which support an arbitrary number of such pairs. we compute the masses of these multi - bound state solitons, and prove that only bag configurations which bear a single pair of bound states are stable. each one of these configurations gives rise to an o ( 2n ) antisymmetric tensor multiplet of soliton states, as in the massless gross - neveu model. | arxiv:hep-th/0509019 |
two interacting electrons in a harmonic oscillator potential under the influence of a perpendicular homogeneous magnetic field are considered. analytic expressions are obtained for the energy spectrum of the two - and three - dimensional cases. exact conditions for phase transitions due to the electron - electron interaction in a quantum dot as a function of the dot size and magnetic field are calculated. | arxiv:cond-mat/9704202 |
we study a conjecture, due to voisin, on 0 - cycles on varieties with $ p _ g = 1 $. using kimura ' s finite dimensional motives and recent results of vial ' s on the refined ( chow - ) k \ " unneth decomposition, we provide a general criterion for calabi - yau manifolds of dimension at most $ 5 $ to verify voisin ' s conjecture. we then check, using in most cases some cohomological computations on the mirror partners, that the criterion can be successfully applied to various examples in each dimension up to $ 5 $. | arxiv:1706.00472 |
appear. these included a treatise on forensic medicine and public health by the french physician francois - emmanuel fodere and the complete system of police medicine by the german medical expert johann peter frank. as the rational values of the enlightenment era increasingly permeated society in the 18th century, criminal investigation became a more evidence - based, rational procedure − the use of torture to force confessions was curtailed, and belief in witchcraft and other powers of the occult largely ceased to influence the court ' s decisions. two examples of english forensic science in individual legal proceedings demonstrate the increasing use of logic and procedure in criminal investigations at the time. in 1784, in lancaster, john toms was tried and convicted for murdering edward culshaw with a pistol. when the dead body of culshaw was examined, a pistol wad ( crushed paper used to secure powder and balls in the muzzle ) found in his head wound matched perfectly with a torn newspaper found in toms ' s pocket, leading to the conviction. in warwick 1816, a farm laborer was tried and convicted of the murder of a young maidservant. she had been drowned in a shallow pool and bore the marks of violent assault. the police found footprints and an impression from corduroy cloth with a sewn patch in the damp earth near the pool. there were also scattered grains of wheat and chaff. the breeches of a farm labourer who had been threshing wheat nearby were examined and corresponded exactly to the impression in the earth near the pool. an article appearing in scientific american in 1885 describes the use of microscopy to distinguish between the blood of two persons in a criminal case in chicago. = = = chromatography = = = chromatography is a common technique used in the field of forensic science. chromatography is a method of separating the components of a mixture from a mobile phase. chromatography is an essential tool used in forensic science, helping analysts identify and compare trace amounts of samples including ignitable liquids, drugs, and biological samples. many laboratories utilize gas chromatography / mass spectrometry ( gc / ms ) to examine these kinds of samples ; this analysis provides rapid and reliant data to identify samples in question. = = = toxicology = = = a method for detecting arsenious oxide, simple arsenic, in corpses was devised in 1773 by the swedish chemist, carl wilhelm scheele. his work was expanded upon, in 1806, by german chemist valentin ross, who learned to detect the poison in | https://en.wikipedia.org/wiki/Forensic_science |
we propose an improved analytical model for the horizon - absorbed gravitational - wave energy flux of a small body in circular orbit in the equatorial plane of a kerr black hole. post - newtonian ( pn ) theory provides an analytical description of the multipolar components of the absorption flux through taylor expansions in the orbital frequency. building on previous work, we construct a mode - by - mode factorization of the absorbed flux whose taylor expansion agrees with current pn results. this factorized form significantly improves the agreement with numerical results obtained with a frequency - domain teukolsky code, which evolves through a sequence of circular orbits up to the photon orbit. we perform the comparison between model and numerical data for dimensionless kerr spins $ - 0. 99 \ leq q \ leq 0. 99 $ and for frequencies up to the light ring of the kerr black hole. our proposed model enforces the presence of a zero in the flux at an orbital frequency equal to the frequency of the horizon, as predicted by perturbation theory. it also reproduces the expected divergence of the flux close to the light ring. neither of these features are captured by the taylor - expanded pn flux. our proposed absorption flux can also help improve models for the inspiral, merger, ringdown of small mass - ratio binary systems. | arxiv:1305.2184 |
the study of community networks has attracted considerable attention recently. in this paper, we propose an evolving community network model based on local processes, the addition of new nodes intra - community and new links intra - or inter - community. employing growth and preferential attachment mechanisms, we generate networks with a generalized power - law distribution of nodes ' degrees. | arxiv:0902.0652 |
loop acceleration can be used to prove safety, reachability, runtime bounds, and ( non - ) termination of programs. to this end, a variety of acceleration techniques has been proposed. however, so far all of them have been monolithic, i. e., a single loop could not be accelerated using a combination of several different acceleration techniques. in contrast, we present a calculus that allows for combining acceleration techniques in a modular way and we show how to integrate many existing acceleration techniques into our calculus. moreover, we propose two novel acceleration techniques that can be incorporated into our calculus seamlessly. some of these acceleration techniques apply only to non - terminating loops. thus, combining them with our novel calculus results in a new, modular approach for proving non - termination. an empirical evaluation demonstrates the applicability of our approach, both for loop acceleration and for proving non - termination. | arxiv:2111.13952 |
we propose a framework for the deployment and subsequent autonomic management of component - based distributed applications. an initial deployment goal is specified using a declarative constraint language, expressing constraints over aspects such as component - host mappings and component interconnection topology. a constraint solver is used to find a configuration that satisfies the goal, and the configuration is deployed automatically. the deployed application is instrumented to allow subsequent autonomic management. if, during execution, the manager detects that the original goal is no longer being met, the satisfy / deploy process can be repeated automatically in order to generate a revised deployment that does meet the goal. | arxiv:1006.4730 |
we systematically examine the conditions of obtaining left - handed ( lh ) behavior in photonic crystals. detailed studies of the phase and group velocities as well as the phase np and group ng refractive index are given. the existence of negative refraction does not guarantee the existence of negative index of refraction and so lh behavior. a wedge type of experiment is suggested that can unambiguously distiguinsh between cases of negative refraction that occur when left - handed behavior is present, from cases that show negative refraction without lh behavior. | arxiv:cond-mat/0212434 |
we propose a simple mechanical model for relativistic explosions with both forward and reverse shocks, which allows one to do fast calculations of grb afterglow. the blast wave in the model is governed by pressures p _ f and p _ r at the forward and reverse shocks. we show that the simplest assumption p _ f = p _ r is in general inconsistent with energy conservation law. the model is applied to grbs with non - uniform ejecta. such " stratified fireballs " are likely to emerge with a monotonic velocity profile after an internal - shock stage. we calculate the early afterglow emission expected from stratified fireballs. | arxiv:astro-ph/0601156 |
the discovery of weyl semimetals ( wsms ) has fueled tremendous interest in condensed matter physics. wsms require breaking of either inversion symmetry ( is ) or time - reversal symmetry ( trs ) ; they can be categorized into type - i and type - ii wsms, characterized by un - tilted and strongly tilted weyl cones respectively. type - i wsms with breaking of is or trs and type - ii wsms with is breaking have been realized experimentally, but trs - breaking type - ii wsm still remains elusive. in this article, we report an ideal trs - breaking type - ii wsm with only one pair of weyl nodes observed in the antiferromagnetic topological insulator mn ( bi1 - xsbx ) 2te4 under magnetic fields. this state is manifested by a large intrinsic anomalous hall effect, a non - trivial $ \ mathrm { { \ pi } } $ berry phase of the cyclotron orbit and a large positive magnetoresistance in the ferromagnetic phase at an optimal sample composition. our results establish a promising platform for exploring the physics underlying the long - sought, ideal trs breaking type - ii wsm. | arxiv:2002.10683 |
the way data structures organize data is often a function of the sequence of past operations. the organization of data is referred to as the data structure ' s state, and the sequence of past operations constitutes the data structure ' s history. a data structure state can therefore be used as an oracle to derive information about its history. as a result, for history - sensitive applications, such as privacy in e - voting, incremental signature schemes, and regulatory compliant data retention ; it is imperative to conceal historical information contained within data structure states. data structure history can be hidden by making data structures history independent. in this paper, we explore how to achieve history independence. we observe that current history independence notions are significantly limited in number and scope. there are two existing notions of history independence - - weak history independence ( whi ) and strong history independence ( shi ). whi does not protect against insider adversaries and shi mandates canonical representations, resulting in inefficiency. we postulate the need for a broad, encompassing notion of history independence, which can capture whi, shi, and a broad spectrum of new history independence notions. to this end, we introduce $ \ delta $ history independence ( $ \ delta $ hi ), a generic game - based framework that is malleable enough to accommodate existing and new history independence notions. as an essential step towards formalizing $ \ delta $ hi, we explore the concepts of abstract data types, data structures, machine models, memory representations and history independence. finally, to bridge the gap between theory and practice, we outline a general recipe for building end - to - end, history independent systems and demonstrate the use of the recipe in designing two history independent file systems. | arxiv:1501.06508 |
the very large area gamma - ray space telescope ( vlast ) is a mission concept proposed to detect gamma - ray photons through both the compton scattering and electron - positron pair production mechanisms, enabling the detection of photons with energies ranging from mev to tev. this project aims to conduct a comprehensive survey of the gamma - ray sky from a low earth orbit using an anti - coincidence detector, a tracker detector that also serves as a low energy calorimeter, and a high energy imaging calorimeter. we developed a monte carlo simulation application of the detector with the geant4 toolkit to evaluate the instrument performance including the effective area, angular resolution and energy resolution, as well as explored specific optimizations of the detector configuration. our simulation - based analysis indicates that the vlast ' s current design is physically feasible, with an acceptance larger than 10 ~ $ \ rm m ^ 2 \ sr $ which is four times larger than fermi - lat, an energy resolution better than 2 \ % at 10 ~ gev, and an angular resolution better than 0. 2 degrees at 10 ~ gev. the vlast project is expected to make significant contribution to the field of gamma - ray astronomy and to enhance our understanding of the cosmos. | arxiv:2407.16973 |
this paper studies the dynamical properties of closed - loop systems obtained from control barrier function - based safety filters. we provide a sufficient and necessary condition for the existence of undesirable equilibria and show that the jacobian matrix of the closed - loop system evaluated at an undesirable equilibrium always has a nonpositive eigenvalue. in the special case of linear planar systems and ellipsoidal obstacles, we give a complete characterization of the dynamical properties of the corresponding closed - loop system. we show that for underactuated systems, the safety filter always introduces a single undesirable equilibrium, which is a saddle - point. we prove that all trajectories outside the global stable manifold of such equilibrium converge to the origin. in the fully actuated case, we discuss how the choice of nominal controller affects the stability properties of the closed - loop system. various simulations illustrate our results. | arxiv:2408.00958 |
blockchain technology has emerged as a revolutionary tool in ensuring data integrity and security in digital transactions. however, the current approaches to data verification in blockchain systems, particularly in ethereum, face challenges in terms of efficiency and computational overhead. the traditional use of merkle trees and cryptographic hash functions, while effective, leads to significant resource consumption, especially for large datasets. this highlights a gap in existing research : the need for more efficient methods of data verification in blockchain networks. our study addresses this gap by proposing an innovative aggregation scheme for zero - knowledge proofs within the structure of merkle trees. we develop a system that significantly reduces the size of the proof and the computational resources needed for its generation and verification. our approach represents a paradigm shift in blockchain data verification, balancing security with efficiency. we conducted extensive experimental evaluations using real ethereum block data to validate the effectiveness of our proposed scheme. the results demonstrate a drastic reduction in proof size and computational requirements compared to traditional methods, making the verification process more efficient and economically viable. our contribution fills a critical research void, offering a scalable and secure solution for blockchain data verification. the implications of our work are far - reaching, enhancing the overall performance and adaptability of blockchain technology in various applications, from financial transactions to supply chain management. | arxiv:2402.03834 |
when fragile molecules such as glycine, polyglicine, alkanes, and alkanethiols are embedded in liquid helium nanodroplets, electron - impact ionization of the beam leads to fragmentation which is as extensive as that of isolated gas - phase molecules. however, it turns out that if a few molecules of water are co - embedded with the peptide and alkane chains, their fragmentation is drastically reduced or completely eliminated. on the other hand, the fragmentation of alkanethiols remains unaffected. on the basis of these observations, it is proposed that the fragmentation " buffering " effect may correlate with the magnitude of the impurity ' s electric dipole moment, which steers the migration of the ionizing he ^ + hole in the droplet. | arxiv:0711.3052 |
based on 471 million bb pairs collected with the babar detector at the pep - ii e + e - collider, we perform a series of measurements on rare decays b - > k ( * ) l + l -, where l + l - is either e + e - or mu + mu -. the measurements include total branching fractions, and partial branching fractions in six bins of di - lepton mass - squared. we also measure isospin asymmetries in the same six bins. furthermore, we measure direct cp and lepton flavor asymmetries for di - lepton mass below and above the j / psi resonance. our measurements show good agreement with both standard model predictions and measurements from other experiments. | arxiv:1205.3241 |
over the past few years, various word - level textual attack approaches have been proposed to reveal the vulnerability of deep neural networks used in natural language processing. typically, these approaches involve an important optimization step to determine which substitute to be used for each word in the original input. however, current research on this step is still rather limited, from the perspectives of both problem - understanding and problem - solving. in this paper, we address these issues by uncovering the theoretical properties of the problem and proposing an efficient local search algorithm ( ls ) to solve it. we establish the first provable approximation guarantee on solving the problem in general cases. extensive experiments involving 5 nlp tasks, 8 datasets and 26 nlp models show that ls can largely reduce the number of queries usually by an order of magnitude to achieve high attack success rates. further experiments show that the adversarial examples crafted by ls usually have higher quality, exhibit better transferability, and can bring more robustness improvement to victim models by adversarial training. | arxiv:2109.02229 |
multi - camera multi - target tracking ( mcmt ) is a computer vision technique that involves tracking multiple targets simultaneously across multiple cameras. mcmt in urban traffic visual analysis faces great challenges due to the complex and dynamic nature of urban traffic scenes, where multiple cameras with different views and perspectives are often used to cover a large city - scale area. targets in urban traffic scenes often undergo occlusion, illumination changes, and perspective changes, making it difficult to associate targets across different cameras accurately. to overcome these challenges, we propose a novel systematic mcmt framework, called citytrack. specifically, we present a location - aware scmt tracker which integrates various advanced techniques to improve its effectiveness in the mcmt task and propose a novel box - grained matching ( bgm ) method for the ica module to solve the aforementioned problems. we evaluated our approach on the public test set of the cityflowv2 dataset and achieved an idf1 of 84. 91 %, ranking 1st in the 2022 ai city challenge. our experimental results demonstrate the effectiveness of our approach in overcoming the challenges posed by urban traffic scenes. | arxiv:2307.02753 |
in this note we point out the relation between brion ' s formula for the lattice point generating function of a convex polytope in terms of the vertex cones [ brion1988 ] on the one hand, and the polar decomposition \ ` a la lawrence / varchenko [ lawrence1991, varchenko1987 ] on the other. we then go on to prove a version of polar decomposition for non - simple polytopes. | arxiv:math/0312095 |
we point out that, in the context of the sm, $ | v ^ 2 _ { 13 } | + | v ^ 2 _ { 23 } | $ is expected to be large, of order one. the fact that $ | v ^ 2 _ { 13 } | + | v ^ 2 _ { 23 } | \ approx 1. 6 \ times 10 ^ { - 3 } $ motivates the introduction of a symmetry s which leads to $ v _ { ckm } = { 1 \ > \! \! \! \ mathrm { i } } $, with only the third generation of quarks acquiring mass. we consider two scenarios for generating the mass of the first two quark generations and full quark mixing. one consists of the introduction of a second higgs doublet which is neutral under s. the second scenario consists of assuming new physics at a high energy scale, contributing to the masses of light quark generations, in an effective field theory approach. this last scenario leads to couplings of the higgs particle to $ s \ overline s $ and $ c \ overline c $ which are significantly enhanced with respect to those of the sm. in both schemes, one has scalar - mediated flavour - changing neutral currents which are naturally suppressed. flavour violating top decays are predicted in the second scenario at the level $ \ mbox { br } ( t \ rightarrow h c ) \ geq 5 \ times 10 ^ { - 5 } $. | arxiv:1602.08011 |
it is argued that electron can be treated as an anyon which carries a charge ( - e ) and a magnetic flux $ \ pm \ frac { \ phi _ { 0 } } { 2 } $ in the presence and absence of a uniform external magnetic field. this flux is shown to arise due to the spin of the electron. the flux associated with the electron spin is calculated using a semi - classical model which is based on the magnetic top model. in accordance with spherical top model it is assumed that the spin angular momentum of the electron is produced by the fictitious point charge ( - e ) rotating in a circular orbit. it is shown that the flux through the circular orbit is independent of the radius and $ \ frac { \ phi _ { 0 } } { 2 } $ for a spin down electron and - $ \ frac { \ phi _ { 0 } } { 2 } $ for a spin up one. where $ \ phi _ { 0 } = \ frac { hc } { e } $ is the flux quantum. | arxiv:physics/0205038 |
a class of self - similar sets of entangled quantum states is introduced, for which a recursive definition is provided. these sets, the " bell gems, " are defined by the subsystem exchange symmetry characteristic of the bell states. each bell gem is shown to be an orthonormal basis of maximally entangled elements. a non - trivial example bell gem is presented. quantum circuits for producing the elements of this example from the computational basis states are provided. | arxiv:quant-ph/0407251 |
" perhaps the purest approximation to the truth that has yet been published " on the subject. = = = classical political economy = = = the publication of adam smith ' s the wealth of nations in 1776, has been described as " the effective birth of economics as a separate discipline. " the book identified land, labour, and capital as the three factors of production and the major contributors to a nation ' s wealth, as distinct from the physiocratic idea that only agriculture was productive. smith discusses potential benefits of specialisation by division of labour, including increased labour productivity and gains from trade, whether between town and country or across countries. his " theorem " that " the division of labor is limited by the extent of the market " has been described as the " core of a theory of the functions of firm and industry " and a " fundamental principle of economic organization. " to smith has also been ascribed " the most important substantive proposition in all of economics " and foundation of resource - allocation theory — that, under competition, resource owners ( of labour, land, and capital ) seek their most profitable uses, resulting in an equal rate of return for all uses in equilibrium ( adjusted for apparent differences arising from such factors as training and unemployment ). in an argument that includes " one of the most famous passages in all economics, " smith represents every individual as trying to employ any capital they might command for their own advantage, not that of the society, and for the sake of profit, which is necessary at some level for employing capital in domestic industry, and positively related to the value of produce. in this : he generally, indeed, neither intends to promote the public interest, nor knows how much he is promoting it. by preferring the support of domestic to that of foreign industry, he intends only his own security ; and by directing that industry in such a manner as its produce may be of the greatest value, he intends only his own gain, and he is in this, as in many other cases, led by an invisible hand to promote an end which was no part of his intention. nor is it always the worse for the society that it was no part of it. by pursuing his own interest he frequently promotes that of the society more effectually than when he really intends to promote it. the reverend thomas robert malthus ( 1798 ) used the concept of diminishing returns to explain low living standards. human population, he argued, tended to increase geometrically, outstripping the production of food, which increased arithmetically. the force of a | https://en.wikipedia.org/wiki/Economics |
we study the spectral theory for the first - order system $ ju ' + qu = wf $ of differential equations on the real interval $ ( a, b ) $ when $ j $ is a constant, invertible skew - hermitian matrix and $ q $ and $ w $ are matrices whose entries are distributions of order zero with $ q $ hermitian and $ w $ non - negative. also, we do not pose the definiteness condition customarily required for the coefficients of the equation. specifically, we construct minimal and maximal relations, and study self - adjoint restrictions of the maximal relation. for these we determine green ' s function and prove the existence of a spectral ( or generalized fourier ) transformation. we have a closer look at the special cases when the endpoints of the interval $ ( a, b ) $ are regular as well as the case of a $ 2 \ times2 $ system. two appendices provide necessary details on distributions of order zero and the abstract spectral theory for relations. | arxiv:1807.09653 |
we calculate the highest possible information gain in a measurement of entangled states when employing a beamsplitter. the result is used to evaluate the fidelity, averaged over all unknown inputs, in a realistic teleportation protocol that takes account of the imperfect detection of bell states. finally, we introduce a probabilistic teleportation scheme, where measurements are made in a partially entangled basis. | arxiv:quant-ph/0010113 |
we consider some classes of levy processes for which the estimate of krylov and safonov ( as in [ bl02 ] ) fails and thus it is not possible to use the standard iteration technique to obtain a - priori holder continuity estimates of harmonic functions. despite the faliure of this method, we obtain some a - priori regularity estimates of harmonic functions for these processes. moreover, we extend results from [ ssv06 ] and obtain asymptotic behavior of the green function and the levy density for a large class of subordinate brownian motions, where the laplace exponent of the corresponding subordinator is a slowly varying function. | arxiv:1109.3676 |
recently, an interesting form of non - classical effect which can be considered as a form of contextuality within quantum mechanics, has been demonstrated for a four - level system by discriminating the different routes that are taken for measuring a single observable. in this paper, we provide a simpler version of that proof for a single qutrit, which is also within the formalism of quantum mechanics and without recourse to any realist hidden variable model. the degeneracy of the eigenvalues and the l $ \ ddot { u } $ der projection rule play important role in our proof. | arxiv:1806.01171 |
transition metal molybdenum oxides a2mo3o8 ( a = mn, fe, co ) are known to be polar magnets where a ions are located in either octahedrally or tetrahedrally coordinated sites. in this paper we predict that their polarizations can be reversed via swapping of two coordinations for a ions, giving rise to robust vertical ferroelectricity. such unique ferroelectricity via coordination swapping can be used to control the neel vector in altermagnetic fe2mo3o8, while the large non - relativistic spin - splittings can be also altered by ferroelectric switching in luttinger compensated magnetic mn2mo3o8, both in the absence of net magnetization. however, their ultra - thin layers may possess net magnetizations that can be reversed upon ferroelectric switching. our findings provide a new type of multiferroicity as well as a new avenue in control of antiferromagnetic spintronics. | arxiv:2503.13218 |
in this paper, we study chinese spelling correction ( csc ) as a joint decision made by two separate models : a language model and an error model. through empirical analysis, we find that fine - tuning bert tends to over - fit the error model while under - fit the language model, resulting in poor generalization to out - of - distribution error patterns. given that bert is the backbone of most csc models, this phenomenon has a significant negative impact. to address this issue, we are releasing a multi - domain benchmark lemon, with higher quality and diversity than existing benchmarks, to allow a comprehensive assessment of the open domain generalization of csc models. then, we demonstrate that a very simple strategy, randomly masking 20 \ % non - error tokens from the input sequence during fine - tuning is sufficient for learning a much better language model without sacrificing the error model. this technique can be applied to any model architecture and achieves new state - of - the - art results on sighan, ecspell, and lemon. | arxiv:2305.17721 |
we demonstrate propagation of plasmons in single crystalline silver nanostructures fabricated using a combination of a bottom - up and a top - down approach. silver nanoplates of thickness around 65 nm and a surface area of about 100 \ mu m ^ 2 are made using a wet chemical method. silver nanotips and nanowires are then sculptured by focused ion beam milling. the plasmons are excited by using the fluorescence from the redeposited silver clusters during the milling process. propagation of plasmons in the nanowires is observed in the visible spectral region. we also observe a cavity effect by measuring the emission spectrum from the distal wire end. | arxiv:1306.4453 |
we consider a general class of decision problems concerning formal languages, called ` ` ( one - dimensional ) unboundedness predicates ' ', for automata that feature reversal - bounded counters ( rbca ). we show that each problem in this class reduces - - non - deterministically in polynomial time - - to the same problem for just finite automata. we also show an analogous reduction for automata that have access to both a pushdown stack and reversal - bounded counters ( prbca ). this allows us to answer several open questions : for example, we show that it is conp - complete to decide whether a given ( p ) rbca language $ l $ is bounded, meaning whether there exist words $ w _ 1, \ ldots, w _ n $ with $ l \ subseteq w _ 1 ^ * \ cdots w _ n ^ * $. for prbca, even decidability was open. our methods also show that there is no language of a ( p ) rbca of intermediate growth. this means, the number of words of each length grows either polynomially or exponentially. part of our proof is likely of independent interest : we show that one can translate an rbca into a machine with $ \ mathbb { z } $ - counters in logarithmic space, while preserving the accepted language. | arxiv:2301.10198 |
using finite difference operators, we define a notion of boundary and surface measure for configuration sets under poisson measures. a margulis - russo type identity and a co - area formula are stated with applications to deviation inequalities and functional inequalities, and bounds are obtained on the associated isoperimetric constants. | arxiv:2103.11546 |
one of the most effective ways to test stellar evolutionary models is to measure dynamical masses for binary systems at a range of temperatures. in this paper, we present orbits of three young k + m binary systems in taurus ( hubble ~ 4, ff ~ tau, and hp ~ tau / g3 ) with vlbi parallaxes. we obtained precision astrometry with keck - ii / nirc2, optical photometry with hst / wfc3, and low - resolution optical spectra with wifes on the anu 2. 3 m telescope. we fit orbital solutions and dynamical masses with uncertainties of 1 - 5 % for the three binary systems. the spectrum, photometry, and mass for hubble ~ 4 are inconsistent with a binary system, suggesting that it may be a triple system where the primary component consists of two stars. for hp ~ tau / g3 and ff ~ tau, model masses derived from sed determined component temperatures and luminosities agree with the dynamical masses, with a small offset towards larger model masses. we find model ages for the primary components of these systems of $ \ sim $ 3 myr, but find that the secondaries appear younger by a factor of two. these estimates also disagree with the age of the physically associated g - type star hp ~ tau / g2, which is older ( $ \ sim $ 5 myr ) according to the same models. this discrepancy is equivalent to a luminosity under - prediction of 0. 1 - 0. 2 dex, or a temperature over - prediction of 100 - 300 k, for k / m - type stars at a given model age. we interpret this as further evidence for a systematic error in pre - main sequence evolutionary tracks for convective stars. our results reinforce that the ages of young populations determined from the locus of m - type members on the hr - diagram may require upward revision. | arxiv:1911.12378 |
the past few years have witnessed a boom of miniapps, as lightweight applications, miniapps are of great importance in the mobile internet sector. consequently, the security of miniapps can directly impact compromising the integrity of sensitive data, posing a potential threat to user privacy. however, after a thorough review of the various research efforts in miniapp security, we found that their actions in researching the safety of miniapp web interfaces are limited. this paper proposes a triad threat model focusing on users, servers and attackers to mitigate the security risk of miniapps. by following the principle of least privilege and the direction of permission consistency, we design a novel analysis framework for the security risk assessment of miniapps by this model. then, we analyzed the correlation between the security risk assessment and the threat model associated with the miniapp. this analysis led to identifying potential scopes and categorisations with security risks. in the case study, we identify nine major categories of vulnerability issues, such as sql injection, logical vulnerabilities and cross - site scripting. we also assessed a total of 50, 628 security risk hazards and provided specific examples. | arxiv:2311.11382 |
in this paper, we consider minimal hypersurfaces in the product space $ \ mathbb { h } ^ n \ times \ mathbb { r } $. we begin by studying examples of rotation hypersurfaces and hypersurfaces invariant under hyperbolic translations. we then consider minimal hypersurfaces with finite total curvature. this assumption implies that the corresponding curvature goes to zero uniformly at infinity. we show that surfaces with finite total intrinsic curvature have finite index. the converse statement is not true as shown by our examples which also serve as useful barriers. | arxiv:0808.3838 |
infrastructure is an indispensable part of human life. over the past decades, the human - computer interaction ( hci ) community has paid increasing attention to human interactions with infrastructure. in this paper, we conducted a systematic literature review on infrastructure studies in sigchi, one of the most influential communities in hci. we collected a total of 190 primary studies, covering works published between 2006 and 2024. most of these studies are inspired by susan leigh star ' s notion of infrastructure. we identify three major themes in infrastructure studies : growing infrastructure, appropriating infrastructure, and coping with infrastructure. our review highlights a prevailing trend in sigchi ' s infrastructure research : a focus on informal infrastructural activities across various sociotechnical contexts. in particular, we examine studies that problematize infrastructure and alert the hci community to its potentially harmful aspects. | arxiv:2504.09612 |
scientific simulation codes are public property sustained by the community. modern technology allows anyone to join scientific software projects, from anywhere, remotely via the internet. the phonopy and phono3py codes are widely used open source phonon calculation codes. this review describes a collection of computational methods and techniques as implemented in these codes and shows their implementation strategies as a whole, aiming to be useful for the community. some of the techniques presented here are not limited to phonon calculations and may therefore be useful in other area of condensed matter physics. | arxiv:2301.05784 |
we propose a differential hydrodynamic response relation, $ v _ 2 ( \ zeta ) = \ int d \ xi g ( \ zeta - \ xi ) \ mathcal { e } _ 2 ( \ xi ) $, to describe the formation of a pseudorapidity dependent elliptic flow in heavy - ion collisions, in response to a fluctuating three - dimensional initial density profile. by analyzing the medium expansion using event - by - event simulations of 3 + 1d music, with initial conditions generated via the ampt model, the differential response relation is verified. given the response relation, we are able to separate the two - point correlation of elliptic flow in pseudorapidity into fluid response and two - point correlation of initial eccentricity. the fluid response contains information of the speed of sound and shear viscosity of the medium. from the pseudorapidity dependent response relation, a finite radius of convergence of hydrodynamic gradient expansion is obtained with respect to realistic fluids in heavy - ion collisions. | arxiv:1907.10854 |
we present a general solution to the problem of determining all s - dual descriptions for a specific ( but very rich ) class of $ \ mathcal { n } = 1 $ scfts. these scfts are indexed by decorated toric diagrams, and can be engineered in string theory by probing orientifolds of isolated toric singularities with d3 branes. the s - dual phases are described by quiver gauge theories coupled to specific types of conformal matter which we describe explicitly. we illustrate our construction with many examples, including s - dualities in previously unknown scfts. | arxiv:1612.00853 |
that was not necessary to mathematical practice in any real sense. he advocated a form of " pure realism " that rejected mystical notions of truth and accepted much quasi - empiricism in mathematics. this grew from the increasingly popular assertion in the late 20th century that no one foundation of mathematics could be ever proven to exist. it is also sometimes called " postmodernism in mathematics " although that term is considered overloaded by some and insulting by others. quasi - empiricism argues that in doing their research, mathematicians test hypotheses as well as prove theorems. a mathematical argument can transmit falsity from the conclusion to the premises just as well as it can transmit truth from the premises to the conclusion. putnam has argued that any theory of mathematical realism would include quasi - empirical methods. he proposed that an alien species doing mathematics might well rely on quasi - empirical methods primarily, being willing often to forgo rigorous and axiomatic proofs, and still be doing mathematics — at perhaps a somewhat greater risk of failure of their calculations. he gave a detailed argument for this in new directions. quasi - empiricism was also developed by imre lakatos. the most important criticism of empirical views of mathematics is approximately the same as that raised against mill. if mathematics is just as empirical as the other sciences, then this suggests that its results are just as fallible as theirs, and just as contingent. in mill ' s case the empirical justification comes directly, while in quine ' s case it comes indirectly, through the coherence of our scientific theory as a whole, i. e. consilience after e. o. wilson. quine suggests that mathematics seems completely certain because the role it plays in our web of belief is extraordinarily central, and that it would be extremely difficult for us to revise it, though not impossible. for a philosophy of mathematics that attempts to overcome some of the shortcomings of quine and godel ' s approaches by taking aspects of each see penelope maddy ' s realism in mathematics. another example of a realist theory is the embodied mind theory. for experimental evidence suggesting that human infants can do elementary arithmetic, see brian butterworth. = = = fictionalism = = = mathematical fictionalism was brought to fame in 1980 when hartry field published science without numbers, which rejected and in fact reversed quine ' s indispensability argument. where quine suggested that mathematics was indispensable for our best scientific theories, and therefore should be | https://en.wikipedia.org/wiki/Philosophy_of_mathematics |
a reentrant behavior of temperature dependent magnetic ac - susceptibility ( or excess susceptibility ( es ) ) at lower temperature is observed in a composite made of superconductor $ la _ { 1. 85 } sr _ { 0. 15 } cuo _ 4 $ ( lcu ) and an insulating paramagnetic salt $ gd _ 2o _ 3 $ ( gdo ). the es exhibits an exponential characteristic that varies with temperature ( $ \ exp, [ \ frac { t _ 0 } { t } ] $ ), t0 is characteristics temperature. the characteristics temperature, t $ _ 0 $, decreases as the effective interface diminishes and the amplitude of the dc magnetic field increases. the creation of ferromagnetic dimers between gd $ ^ { + 3 } $ ions in gdo is observed as a result of vortex - dipole interaction, which causes the observation of this unusual es at temperatures much lower than the superconducting onset temperature t $ _ { s } ^ { onset } $. this type of ferromagnetic dimer formation much below superconducting transition temperature is found comparable with the formation of yu - shiba - rusinov ( ysr ) state and interaction between these ysr state. | arxiv:2407.00715 |
let $ a $ be a finite dimensional algebra over a field $ k $ and $ \ textbf { p } $ be a 2 - term silting complex in $ k ^ { b } ( \ text { proj } a ) $. in this paper, we investigate the representation dimension of $ \ text { end } _ { d ^ { b } ( a ) } ( \ textbf { p } ) $ by using the silting theory. we show that if $ \ textbf { p } $ is a separating silting complex with certain homological restriction, then rep. dim $ a = $ rep. dim $ \ text { end } _ { d ^ { b } ( a ) } ( \ textbf { p } ) $. this gives a proper generalization of the classical compare theorem of representation dimensions showed by chen and hu. it is well - known that $ \ text { h } ^ { 0 } ( \ textbf { p } ) $ is a tilting $ a / \ text { ann } _ { a } ( \ textbf { p } ) $ - module. we also show that rep. dim $ \ text { end } _ { a } ( \ text { h } ^ { 0 } ( \ textbf { p } ) ) = $ rep. dim $ a / \ text { ann } _ { a } ( \ textbf { p } ) $ if $ \ textbf { p } $ is a separating and splitting silting complex. | arxiv:2002.04582 |
this paper computes the bases of the image of $ 2 $ - adic logarithm on the group of the principal units in all 7 quadratic extensions of $ \ mathbb { q } _ 2 $. this helps one to understand the free module structure of $ 2 $ - adic logarithm at arbitrary points on its domain. we discuss some applications at the end. | arxiv:1907.06437 |
a large class of quantum theories of gravity show that the heisenberg ' s uncertainty principle is modified to the " generalised uncertainty principle " ( gup ) near the planckian scale. it has also been shown that the gup induces perturbative corrections to all quantum mechanical hamiltonians, even at low energies, and thereby introduces planck scale corrections to the schr \ " odinger equation and to the relativistic quantum mechanical equations. some of these corrections give rise to potentially measurable effects in the low - energy laboratory. another prediction of these corrections is that a measured length must be quantized, as seen by studying the solutions of the gup modified schr \ " odinger, klein - gordon, and dirac equations in a one, two, and three dimensional box. this result was subsequently extended to spacetimes with weak gravitational fields. in this work, we further extend this length quantization to spacetimes with strong gravitational fields and show that this result continues to hold, thereby showing that it is robust. | arxiv:2006.05781 |
this volume constitutes the informal proceedings of the 32nd international symposium on logic - based program synthesis and transformation ( lopstr 2022 ), held on 21 - 23rd september 2022 as a hybrid ( blended ) meeting, both in - person ( at the ivane javakhishvili tbilisi state university - tsu - in tbilisi, georgia ) and virtual, and co - located with the 24th international symposium on principles and practice of declarative programming ( ppdp 2022 ) as part of the computational logic autumn summit 2022 ( clas 2022 ). | arxiv:2208.04235 |
using the ideas of supersymmetry and shape invariance we show that the eigenvalues and eigenfunctions of a wide class of noncentral potentials can be obtained in a closed form by the operator method. this generalization considerably extends the list of exactly solvable potentials for which the solution can be obtained algebraically in a simple and elegant manner. as an illustration, we discuss in detail the example of the potential $ $ v ( r, \ theta, \ phi ) = { \ omega ^ 2 \ over 4 } r ^ 2 + { \ delta \ over r ^ 2 } + { c \ over r ^ 2 sin ^ 2 \ theta } + { d \ over r ^ 2 cos ^ 2 \ theta } + { f \ over r ^ 2 sin ^ 2 \ theta sin ^ 2 \ alpha \ phi } + { g \ over r ^ 2 sin ^ 2 \ theta cos ^ 2 \ alpha \ phi } $ $ with 7 parameters. other algebraically solvable examples are also given. | arxiv:hep-th/9310104 |
the njl model is formulated on the light cone. using the 1 / n expansion to solve the fermionic constraint, an effective 4 - fermi lagrangian is derived. pionic properties are investigated using this lagrangian, and the formal equivalence to the equal - time formulation is demonstrated. two regularization schemes in terms of light - cone variables are discussed : an extension of the ' invariant mass cut - off scheme ', and a transverse momentum cut - off scheme. it is shown that the first one is equivalent to the covariant 3 - momentum cut - off ( dispersion cut - off ) scheme in the equal - time formulation. as an application the structure function of the pion is studied in both regularization schemes. | arxiv:hep-ph/9901377 |
implantable brain - machine interfaces ( bmis ) are promising for motor rehabilitation and mobility augmentation, and they demand accurate and energy - efficient algorithms. in this paper, we propose a novel spiking neural network ( snn ) decoder for regression tasks for implantable bmis. the snn is trained with enhanced spatio - temporal backpropagation to fully leverage its capability to handle temporal problems. the proposed snn decoder outperforms the state - of - the - art kalman filter and artificial neural network ( ann ) decoders in offline finger velocity decoding tasks. the decoder is deployed on a risc - v - based hardware platform and optimized to exploit sparsity. the proposed implementation has an average power consumption of 0. 50 mw in a duty - cycled mode. when conducting continuous inference without duty - cycling, it achieves an energy efficiency of 1. 88 uj per inference, which is 5. 5x less than the baseline ann. additionally, the average decoding latency is 0. 12 ms for each inference, which is 5. 7x faster than the ann implementation. | arxiv:2405.02146 |
the realization of spin - orbit coupling ( soc ) in ultracold atoms has triggered an intensive exploring of topological superfluids in the degenerate fermi gases based on mean - field theory, which has not yet been reported in experiments. here, we demonstrate the topological phase transitions in the system via the numerically exact quantum monte carlo method. without prior assumptions, our unbiased real - space calculation shows that spin - orbit coupling can stabilize an unconventional pairing in the weak soc regime, in which the fulde - ferrell - larkin - ovchinnikov pairing coexists with the bardeen - cooper - schrieffer pairing. furthermore, we use the jumps in the spin polarization at the time - reversal invariant momenta to qualify the topological phase transition, where we find the critical exponent deviated from the mean - field theory. our results pave the way for the searching of unconventional pairing and topological superfluids with degenerate fermi gases. | arxiv:2109.04670 |
one of the most pressing issues in cosmology is whether general relativity ( gr ) plus a dark sector is the underlying physical theory or whether a modified gravity model is needed. upcoming dark energy experiments designed to probe dark energy with multiple methods can address this question by comparing the results of the different methods in constraining dark energy parameters. disagreement would signal the breakdown of the assumed model ( gr plus dark energy ). we study the power of this consistency test by projecting constraints in the $ w _ 0 - w _ a $ plane from the four different techniques of the dark energy survey in the event that the underlying true model is modified gravity. we find that the standard technique of looking for overlap has some shortcomings, and we propose an alternative, more powerful multi - dimensional consistency test. we introduce the methodology for projecting whether a given experiment will be able to use this test to distinguish a modified gravity model from gr. | arxiv:1004.4810 |
motivation : engineering high - affinity binders targeting specific antigenic determinants remains a challenging and often daunting task, requiring extensive experimental screening. computational methods have the potential to accelerate this process, reducing costs and time, but only if they demonstrate broad applicability and efficiency in exploring mutations, evaluating affinity, and pruning unproductive mutation paths. results : in response to these challenges, we introduce a new computational platform for optimizing protein binders towards their targets. the platform is organized as a series of modules, performing mutation selection and application, molecular dynamics ( md ) simulations to sample conformations around interaction poses, and mutation prioritization using suitable scoring functions. notably, the platform supports parallel exploration of different mutation streams, enabling in silico high - throughput screening on hpc systems. furthermore, the platform is highly customizable, allowing users to implement their own protocols. availability and implementation : the source code is available at https : / / github. com / pgbarletta / locuaz and documentation is at https : / / locuaz. readthedocs. io / | arxiv:2404.09370 |
we present the fourth installment of the yale / san juan southern proper motion catalog, spm4. the spm4 contains absolute proper motions, celestial coordinates, and ( b, v ) photometry for over 103 million stars and galaxies between the south celestial pole and - 20 deg declination. the catalog is roughly complete to v = 17. 5 and is based on photographic and ccd observations taken with the yale southern observatory ' s double - astrograph at cesco observatory in el leoncito, argentina. the proper - motion precision, for well - measured stars, is estimated to be 2 to 3 mas / yr, depending on the type of second - epoch material. at the bright end, proper motions are on the international celestial reference system by way of hipparcos catalog stars, while the faint end is anchored to the inertial system using external galaxies. systematic uncertainties in the absolute proper motions are on the order of 1 mas / yr. | arxiv:1104.5708 |
we study the existence of solutions for a class of nonlinear schr \ " odinger equations involving a magnetic field with mixed dirichlet - neumann boundary conditions. we use lyusternik - shnirelman category and the morse theory to estimate the number of nontrivial solutions in terms of the topology of the part of the boundary where the neumann condition is prescribed. | arxiv:1309.4691 |
the aim of the paper is to study the ring of differential operators $ \ mathcal { d } ( a ( m ) ) $ on the generalized multi - cusp algebra $ a ( m ) $ where $ m \ in \ mathbb { n } ^ n $ ( of krull dimension $ n $ ). the algebra $ a ( m ) $ is singular apart from the single case when $ m = ( 1, \ ldots, 1 ) $. in this case, the algebra $ a ( m ) $ is a polynomial algebra in $ n $ variables. so, the $ n $ ' th weyl algebra $ a _ n = \ mathcal { d } ( a ( 1, \ ldots, 1 ) ) $ is a member of the family of algebras $ \ mathcal { d } ( a ( m ) ) $. we prove that the algebra $ \ mathcal { d } ( a ( m ) ) $ is a central, simple, $ \ mathbb { z } ^ n $ - graded, finitely generated noetherian domain of gelfand - kirillov dimension $ 2n $. explicit finite sets of generators and defining relations is given for the algebra $ \ mathcal { d } ( a ( m ) ) $. we prove that the krull dimension and the global dimension of the algebra $ \ mathcal { d } ( a ( m ) ) $ is $ n $. an analogue of the inequality of bernstein is proven. in the case when $ n = 1 $, simple $ \ mathcal { d } ( a ( m ) ) $ - modules are classified. | arxiv:2312.17303 |
we present a polarization - resolved photoluminescence study of the exchange interaction effects in a prototype system consisting of an individual fe2 + ion and a single neutral exciton confined in a cdse / znse quantum dot. maximal possible number of eight fully linearly - polarized lines in the bright exciton emission spectrum is observed, evidencing complete degeneracy lifting in the investigated system. we discuss conditions required for such a scenario to take place : anisotropy of the electron - hole interaction and the zero - field splitting of the fe2 + ion spin states. neglecting of either of these components is shown to restore partial degeneracy of the transitions, making the excitonic spectrum similar to those previously reported for all other systems of quantum dots with single magnetic dopants. | arxiv:1702.06094 |
strain engineering refers to a general strategy employed in semiconductor manufacturing to enhance device performance. performance benefits are achieved by modulating strain, as one example, in the transistor channel, which enhances electron mobility ( or hole mobility ) and thereby conductivity through the channel. another example are semiconductor photocatalysts strain - engineered for more effective use of sunlight. = = in cmos manufacturing = = the use of various strain engineering techniques has been reported by many prominent microprocessor manufacturers, including amd, ibm, and intel, primarily with regards to sub - 130 nm technologies. one key consideration in using strain engineering in cmos technologies is that pmos and nmos respond differently to different types of strain. specifically, pmos performance is best served by applying compressive strain to the channel, whereas nmos receives benefit from tensile strain. many approaches to strain engineering induce strain locally, allowing both n - channel and p - channel strain to be modulated independently. one prominent approach involves the use of a strain - inducing capping layer. cvd silicon nitride is a common choice for a strained capping layer, in that the magnitude and type of strain ( e. g. tensile vs compressive ) may be adjusted by modulating the deposition conditions, especially temperature. standard lithography patterning techniques can be used to selectively deposit strain - inducing capping layers, to deposit a compressive film over only the pmos, for example. capping layers are key to the dual stress liner ( dsl ) approach reported by ibm - amd. in the dsl process, standard patterning and lithography techniques are used to selectively deposit a tensile silicon nitride film over the nmos and a compressive silicon nitride film over the pmos. a second prominent approach involves the use of a silicon - rich solid solution, especially silicon - germanium, to modulate channel strain. one manufacturing method involves epitaxial growth of silicon on top of a relaxed silicon - germanium underlayer. tensile strain is induced in the silicon as the lattice of the silicon layer is stretched to mimic the larger lattice constant of the underlying silicon - germanium. conversely, compressive strain could be induced by using a solid solution with a smaller lattice constant, such as silicon - carbon. see, e. g., u. s. patent no. 7, 023, 018. another closely related method involves replacing the source and drain region of a mosfet with silicon - german | https://en.wikipedia.org/wiki/Strain_engineering |
applying the unitary clothing transformation method in the model of charged spinless nucleons and neutral mesons interacting via the three - linear yukawa - type coupling, the expression for the charge shift in the third order in the coupling constant is derived. being determined off the energy shell, the ex - pression can be reduced on the energy shell to the explicitly covariant form, providing the independence of the particle momenta. comparison with the cor - responding result of the dyson covariant perturbation theory is performed by es - tablishing the link between the old - fashioned perturbation theory and the cloth - ing approach. | arxiv:nucl-th/0701071 |
in 60 inverse - pb of data taken on the psi ( 3770 ) resonance with the cleo - c detector, we find 8 d + - > mu + nu decay candidates that are mostly signal, containing only 1 estimated background. using this statistically compelling sample, we measure a value of b ( d + - > mu + nu ) = ( 3. 5 + / - 1. 4 + / - 0. 6 ) x10 ^ ( - 4 ), and determine fd + = ( 202 + / - 41 + / - 17 ) mev. | arxiv:hep-ex/0411050 |
by investigating the benefits and shortcomings of the existing form of continuous defect theory ( cdt ) and using recent advancements in size - dependent continuum mechanics, we develop a fully coherent theoretical framework, denoted as consistent continuous defect theory ( c - cdt ). among several important potential applications, c - cdt may provide a proper foundation to study the continuum theory of crystal plasticity. the development presented here includes an examination of the character of the bend - twist tensor, weingarten ' s theorem, burgers and frank vectors, continuous dislocation and disclination density tensors, and the dualism between geometry and statics of cdt based on couple stress theory ( cst ). then, by using consistent couple stress theory ( c - cst ), the new c - cdt is derived in a totally systematic manner. in this development, the geometry of c - cdt is dual to the statics formulation in c - cst. previously, the fundamental step in the creation of c - cst was recognizing the skew - symmetric character of the couple - stress tensor, which requires the skew - symmetrical part of the bend - twist tensor to be the additional measure of deformation in size - dependent continuum mechanics. via weingarten ' s theorem and arguments from c - cst, we establish that in defect theory the dislocation density tensor must be skew - symmetric and thus can be represented by an equivalent dislocation density vector. in addition, we investigate the character of a classical version of c - cdt with unexpected consequences. for full consistency, there can be no continuous dislocation density tensor within classical continuum mechanics, and the continuous disclination density tensor becomes symmetric. this clearly is analogous to the absence of couple - stresses and the symmetry of force - stresses in classical continuum mechanics. | arxiv:1808.10744 |
the decoherence of quantum fluctuations into classical perturbations during inflation is discussed. a simple quantum mechanical argument, using a spatial particle wavefunction rather than a field description, shows that observable correlations from inflation must have a discrete spectrum, since they originate and freeze into the metric within a compact region. the number of discrete modes is estimated using a holographic bound on the number of degrees of freedom. the discreteness may be detectable in some models ; for example, if there is a fundamental universal frequency spectrum, the inflationary gravitational wave background may be resolvable into discrete emission lines. | arxiv:astro-ph/0504364 |
we show that any totally geodesic submanifold of teichmuller space of dimension greater than one covers a totally geodesic subvariety, and only finitely many totally geodesic subvarieties of dimension greater than one exist in each moduli space. | arxiv:1702.03249 |
we compute the quantum effective action induced by integrating out fermions in yang - mills matrix models on a 4 - dimensional background, expanded in powers of a gauge - invariant uv cutoff. the resulting action is recast into the form of generalized matrix models, manifestly preserving the so ( d ) symmetry of the bare action. this provides noncommutative ( nc ) analogs of the seeley - de witt coefficients for the emergent gravity which arises on nc branes, such as curvature terms. from the gauge theory point of view, this provides strong evidence that the nc n = 4 sym has a hidden so ( 10 ) symmetry even at the quantum level, which is spontaneously broken by the space - time background. the geometrical view proves to be very powerful, and allows to predict non - trivial loop computations in the gauge theory. | arxiv:1012.4344 |
sensitive observations with alma allow astronomers to observe the detailed distributions of molecules with relatively weak intensity in nearby galaxies. in particular, we report distributions of several molecular transitions including shock and dust related species ( $ ^ { 13 } $ co $ j $ = 1 - - 0, c $ ^ { 18 } $ o $ j $ = 1 - - 0, $ ^ { 13 } $ cn $ n $ = 1 - - 0, cs $ j $ = 2 - - 1, so $ j _ n $ = 3 $ _ 2 $ - - 2 $ _ 1 $, hnco $ j _ { ka, kc } $ = 5 $ _ { 0, 5 } $ - - 4 $ _ { 0, 4 } $, hc $ _ 3 $ n $ j $ = 11 - - 10, 12 - - 11, ch $ _ 3 $ oh $ j _ k $ = 2 $ _ k $ - - 1 $ _ k $, and ch $ _ 3 $ cn $ j _ k $ = 6 $ _ k $ - - 5 $ _ k $ ) in the nearby seyfert 2 galaxy ngc 1068 observed with the alma early science program. the central $ \ sim $ 1 arcmin ( $ \ sim $ 4. 3 kpc ) of this galaxy was observed in the 100 ghz region covering $ \ sim $ 96 - - 100 ghz and $ \ sim $ 108 - - 111 ghz with an angular resolution of $ \ sim4 " \ times2 " $ ( 290 pc $ \ times $ 140 pc ) to study the effects of an active galactic nucleus and its surrounding starburst ring on molecular abundances. here, we present images and report a classification of molecular distributions into three main categories : ( 1 ) molecules concentrated in the circumnuclear disk ( cnd ) ( so $ j _ n $ = 3 $ _ 2 $ - - 2 $ _ 1 $, hc $ _ 3 $ n $ j $ = 11 - - 10, 12 - - 11, and ch $ _ 3 $ cn $ j _ k $ = 6 $ _ k $ - - 5 $ _ k $ ), ( 2 ) molecules distributed both in the cnd and the starburst ring ( cs $ j $ = 2 - - 1 and ch $ _ 3 $ oh $ j _ k $ = 2 $ _ k $ - - 1 $ _ k $ ), ( 3 ) molecules distributed mainly in the starburst ring ( $ ^ { 13 } $ | arxiv:1406.0782 |
we shall prove that a moduli space of flat irreducible lie algebroid connections over a compact manifold has locally a natural structure of a smooth differentiable space. this is a generalization of some well known results for the moduli space of holomorphic structures on a complex vector bundle over a compact complex manifold. | arxiv:1012.3180 |
the space of metric measure spaces ( complete separable metric spaces with a probability measure ) is becoming more and more important as state space for stochastic processes. of particular interest is the subspace of ( continuum ) metric measure trees. greven, pfaffelhuber and winter introduced the gromov - prohorov metric d _ { gpw } on the space of metric measure spaces and showed that it induces the gromov - weak topology. they also conjectured that this topology coincides with the topology induced by gromov ' s box _ 1 metric. here, we show that this is indeed true, and the metrics are even bi - lipschitz equivalent. more precisely, d _ { gpw } = 1 / 2 box _ { 1 / 2 }, and hence d _ { gpw } < = box _ 1 < = 2d _ { gpw }. the fact that different approaches lead to equivalent metrics underlines their importance and also that of the induced gromov - weak topology. as an application, we give an easy proof of the known fact that the map associating to a lower semi - continuous excursion the coded r - tree is lipschitz continuous when the excursions are endowed with the ( non - separable ) uniform metric. we also introduce a new, weaker, metric topology on excursions, which has the advantage of being separable and making the space of bounded excursions a lusin space. we obtain continuity also for this new topology. | arxiv:1111.5837 |
we consider long, finite - width strips of ising spins with randomly distributed couplings. frustration is introduced by allowing both ferro - and antiferromagnetic interactions. free energy and spin - spin correlation functions are calculated by transfer - matrix methods. numerical derivatives and finite - size scaling concepts allow estimates of the usual critical exponents $ \ gamma / \ nu $, $ \ alpha / \ nu $ and $ \ nu $ to be obtained, whenever a second - order transition is present. low - temperature ordering persists for suitably small concentrations of frustrated bonds, with a transition governed by pure - - ising exponents. contrary to the unfrustrated case, subdominant terms do not fit a simple, logarithmic - enhancement form. our analysis also suggests a vertical critical line at and below the nishimori point. approaching this point along either the temperature axis or the nishimori line, one finds non - diverging specific heats. a percolation - like ratio $ \ gamma / \ nu $ is found upon analysis of the uniform susceptibility at the nishimori point. our data are also consistent with frustration inducing a breakdown of the relationship between correlation - length amplitude and critical exponents, predicted by conformal invariance for pure systems. | arxiv:cond-mat/9906114 |
stage - iv galaxy surveys will measure correlations at small cosmological scales with high signal - to - noise ratio. one of the main challenges of extracting information from small scales is devising accurate models, as well as characterizing the theoretical uncertainties associated with any given model. in this work, we explore the mitigation of theoretical uncertainty due to nonlinear galaxy bias in the context of photometric 2 $ \ times $ 2 - pt analyses. we consider linear galaxy bias as the fiducial model and derive the contribution to the covariance matrix induced by neglected higher - order bias. we construct a covariance matrix for the theoretical error in galaxy clustering and galaxy - galaxy lensing using simulation - based relations that connect higher - order parameters to linear bias. we test the modified likelihood in 2 $ \ times $ 2 - pt analyses based on two sets of mock data vectors : ( 1 ) simulated data vectors, constructed from those same relations between bias parameters, and ( 2 ) data vectors based on the abacussummit simulation suite. we then compare the performance of the theoretical - error approach to the commonly employed scale cuts. we find most theoretical - error configurations yield results equivalent to the scale cuts in terms of precision and accuracy, in some cases producing significantly stronger bounds on cosmological parameters. these results are independent of the maximum scale $ k _ \ mathrm { max } $ in the analysis with theoretical error. the scenarios where linear bias supplemented by theoretical error is unable to recover unbiased cosmology are connected to inadequate modeling of the $ gg $ - $ g \ kappa $ covariance of theoretical error. in view of its removing the ambiguity in the choice of $ k _ \ mathrm { max } $, as well as the possibility of attaining higher precision than the usual scale cuts, we consider this method to be promising for analyses of lss in upcoming photometric galaxy surveys. | arxiv:2410.08930 |
a new class of spatially - coupled turbo - like codes ( sc - tcs ), dubbed generalized spatially coupled parallel concatenated codes ( gsc - pccs ), is introduced. these codes are constructed by applying spatial coupling on parallel concatenated codes ( pccs ) with a fraction of information bits repeated $ q $ times. gsc - pccs can be seen as a generalization of the original spatially - coupled parallel concatenated codes proposed by moloudi et al. [ 2 ]. to characterize the asymptotic performance of gsc - pccs, we derive the corresponding density evolution equations and compute their decoding thresholds. the threshold saturation effect is observed and proven. most importantly, we rigorously prove that any rate - $ r $ gsc - pcc ensemble with 2 - state convolutional component codes achieves at least a fraction $ 1 - \ frac { r } { r + q } $ of the capacity of the binary erasure channel ( bec ) for repetition factor $ q \ geq2 $ and this multiplicative gap vanishes as $ q $ tends to infinity. to the best of our knowledge, this is the first class of sc - tcs that are proven to be capacity - achieving. further, the connection between the strength of the component codes, the decoding thresholds of gsc - pccs, and the repetition factor are established. the superiority of the proposed codes with finite blocklength is exemplified by comparing their error performance with that of existing sc - tcs via computer simulations. | arxiv:2201.09414 |
a model of interdependent networks of networks ( non ) has been introduced recently in the context of brain activation to identify the neural collective influencers in the brain non. here we develop a new approach to derive an exact expression for the random percolation transition in erd \ " { o } s - r \ ' enyi non. analytical calculations are in excellent agreement with numerical simulations and highlight the robustness of the non against random node failures. interestingly, the phase diagram of the model unveils particular patterns of interconnectivity for which the non is most vulnerable. our results help to understand the emergence of robustness in such interdependent architectures. | arxiv:1602.06238 |
given multiple copies of a mixed quantum state with an unknown, nondegenerate principal eigenspace, quantum state purification is the task of recovering a quantum state that is closer to the principal eigenstate. a streaming protocol relying on recursive swap tests has been proposed and analysed for noisy depolarized states with arbitrary dimension and noise level. here, we show that the same algorithm applies much more broadly, enabling the purification of arbitrary mixed states with a nondegenerate principal eigenvalue. we demonstrate this through two approaches. in the first approach, we show that, given the largest two eigenvalues, the depolarized noise is the most difficult noise to purify for the recursive swap tests, thus the desirable bounds on performance and cost follow from prior work. in the second approach, we provide a new and direct analysis for the performance of purification using recursive swap tests for the more general noise. we also derive simple lower bounds on the sample complexity, showing that the recursive swap test algorithm attains optimal sample complexity ( up to a constant factor ) in the low - noise regime. | arxiv:2503.22644 |
in this paper, we consider a sturm - - liouville dynamic equation with robin boundary conditions on time scale and investigate the conditions which guarantee that the potential function is specified. | arxiv:1702.07298 |
to understand historical texts, we must be aware that language - - including the emotional connotation attached to words - - changes over time. in this paper, we aim at estimating the emotion which is associated with a given word in former language stages of english and german. emotion is represented following the popular valence - arousal - dominance ( vad ) annotation scheme. while being more expressive than polarity alone, existing word emotion induction methods are typically not suited for addressing it. to overcome this limitation, we present adaptations of two popular algorithms to vad. to measure their effectiveness in diachronic settings, we present the first gold standard for historical word emotions, which was created by scholars with proficiency in the respective language stages and covers both english and german. in contrast to claims in previous work, our findings indicate that hand - selecting small sets of seed words with supposedly stable emotional meaning is actually harmful rather than helpful. | arxiv:1806.08115 |
we propose a relativistic version of the cosmological principle and confront it to the hubble diagram of supernovae and other probes. | arxiv:1210.1468 |
topological quantum computing has recently proven itself to be a very powerful model when considering large - scale, fully error corrected quantum architectures. in addition to its robust nature under hardware errors, it is a software driven method of error corrected computation, with the hardware responsible for only creating a generic quantum resource ( the topological lattice ). computation in this scheme is achieved by the geometric manipulation of holes ( defects ) within the lattice. interactions between logical qubits ( quantum gate operations ) are implemented by using particular arrangements of the defects, such as braids and junctions. we demonstrate that junction - based topological quantum gates allow highly regular and structured implementation of large cnot ( controlled - not ) gate networks, which ultimately form the basis of the error corrected primitives that must be used for an error corrected algorithm. we present a number of heuristics to optimise the area of the resulting structures and therefore the number of the required hardware resources. | arxiv:1302.5182 |
it is shown that the classical dynamics of 1 : 1 resonance interaction between two identical linearly coupled duffing oscillators is equivalent to the symmetric ( non - biased ) case of ` macroscopic ' quantum dynamics of two weakly coupled bose - einstein condensates. the analogy develops through the boson josephson junction equations, however, reduced to a single conservative energy partition ( ep ) oscillator. the derived oscillator is solvable in quadratures, furthermore it admits asymptotic solution in terms of elementary functions after transition to the action - angle variables. energy partition and coherency indexes are introduced to provide a complete characterization of the system dynamic states through the state variables of the ep oscillator. in particular, nonlinear normal and local mode dynamics of the original system associate with equilibrium points of such oscillator. additional equilibrium points - the local modes - may occur on high energy level as a result of the symmetry breaking bifurcation, which is equivalent to the macroscopic quantum self - trapping effect in boson josephson junction. finally, since the hamiltonian of ep oscillator is always quadratic with respect its linear momentum, the idea of second quantization can be explored without usual transition to the rigid pendulum approximation. | arxiv:1205.4842 |
as a motivating problem, we aim to study some special aspects of the marginal distributions of the order statistics for exchangeable and ( more generally ) for minimally stable non - negative random variables $ t _ { 1 },..., t _ { r } $. in any case, we assume that $ t _ { 1 },..., t _ { r } $ are identically distributed, with a common survival function $ \ overline { g } $ and their survival copula is denoted by $ k $. the diagonal ' s and subdiagonals ' sections of $ k $, along with $ \ overline { g } $, are possible tools to describe the information needed to recover the laws of order statistics. when attention is restricted to the absolutely continuous case, such a joint distribution can be described in terms of the associated multivariate conditional hazard rate ( m. c. h. r. ) functions. we then study the distributions of the order statistics of $ t _ { 1 },..., t _ { r } $ also in terms of the system of the m. c. h. r. functions. we compare and, in a sense, we combine the two different approaches in order to obtain different detailed formulas and to analyze some probabilistic aspects for the distributions of interest. this study also leads us to compare the two cases of exchangeable and minimally stable variables both in terms of copulas and of m. c. h. r. functions. the paper concludes with the analysis of two remarkable special cases of stochastic dependence, namely archimedean copulas and load sharing models. this analysis will allow us to provide some illustrative examples, and some discussion about peculiar aspects of our results. | arxiv:2106.08297 |
the summary receiver operating characteristic ( sroc ) curve has been recommended as one important meta - analytical summary to represent the accuracy of a diagnostic test in the presence of heterogeneous cutoff values. however, selective publication of diagnostic studies for meta - analysis can induce publication bias ( pb ) on the estimate of the sroc curve. several sensitivity analysis methods have been developed to quantify pb on the sroc curve, and all these methods utilize parametric selection functions to model the selective publication mechanism. the main contribution of this article is to propose a new sensitivity analysis approach that derives the worst - case bounds for the sroc curve by adopting nonparametric selection functions under minimal assumptions. the estimation procedures of the worst - case bounds use the monte carlo method to obtain the sroc curves along with the corresponding area under the curves in the worst case where the maximum possible pb under a range of marginal selection probabilities is considered. we apply the proposed method to a real - world meta - analysis to show that the worst - case bounds of the sroc curves can provide useful insights for discussing the robustness of meta - analytical findings on diagnostic test accuracy. | arxiv:2401.05124 |
in this paper the mono - layer graphene at the charge neutrality point is considered whithin thomas - fermi - dirac theory, treating inhomogeneous external potentials and electron - electron interactions on equal footing. we present some general considerations concerning the probability measure of the ground state charge density. the system shows degrees of self - similarity. by analyzing the ground state carrier density profile, we show that although it is not gaussian, the critical exponents are consistent with kondev hyper - scaling relations. using schramm - loewner ( sle ) evolution we show that the ungated graphene has conformal invariance and the random zero - charge density contours are sle $ _ { \ kappa } $ with $ \ kappa = 1. 8 \ pm 0. 2 $. | arxiv:1609.07458 |
we present here recent results on the investigations of the mass spectrum ( s - states and p - states ), decay constants, decay widths and life time of the d, $ d _ s $, and $ b _ c $ mesons within the framework of phenomenological potential models. we also present the binding energy and the masses of the di - meson molecular systems with one or more charm meson combinations. many of the newly found experimental open charm states are identified with the orbital excitations of the conventional open charm mesons while others like x ( 3872 ), y ( 3930 ), $ d _ { sj } $ ( 2632, 2700 ) \ emph { etc. }, are identified as molecular like states. | arxiv:0808.1776 |
we consider the maximum of the discrete two dimensional gaussian free field in a box, and prove the existence of a ( dense ) deterministic subsequence along which the maximum, centered at its mean, is tight ; this still leaves open the conjecture that tightness holds without the need for subsequences. the method of proof relies on an argument developed by dekking and host for branching random walks with bounded increments and on comparison results specific to gaussian fields. | arxiv:1005.5417 |
given a closed positive current t on a compact kahler manifold x, we introduce the notion of non - pluripolar product relative to t of closed positive ( 1, 1 ) - currents. we recover the well - known non - pluripolar product when t is the current of integration along x. our main results are a monotonicity property of relative non - pluripolar products, a necessary condition for currents to be of relative full mass intersection in terms of lelong numbers, and the convexity of weighted classes of currents of relative full mass intersection. the former two results are new even when t is the current of integration along x. | arxiv:2004.11111 |
the evaluation of machine learning models using human - labeled validation data can be expensive and time - consuming. ai - labeled synthetic data can be used to decrease the number of human annotations required for this purpose in a process called autoevaluation. we suggest efficient and statistically principled algorithms for this purpose that improve sample efficiency while remaining unbiased. these algorithms increase the effective human - labeled sample size by up to 50 % on experiments with gpt - 4. | arxiv:2403.07008 |
we introduce the notion of composition series of triangulated categories. their \ emph { lengths } yield invariants for these categories. we then focus on composition series of derived categories of certain projective varieties and finite dimensional algebras. we construct composition series of different lengths, for some smooth projective rational surfaces and for certain smooth threefolds. on the other hand, we prove that for derived categories of finite dimensional representations of finite acyclic quivers ( which are allowed to be wild ), for nontrivial admissible subcategories of $ { \ rm d } ^ { \ rm b } ( \ mathbb { p } ^ 2 ) $ and for derived categories of some singular varieties, all composition series have the same length. if this property would also hold for the blow - up of $ \ mathbb { p } ^ 2 $ in $ 10 $ general points, then krah ' s phantom subcategory would have infinite length. in particular, it would have an infinite length chain of thick subcategories. | arxiv:2404.07583 |
quantum communication has been successfully implemented in optical fibres and through free - space [ 1 - 3 ]. fibre systems, though capable of fast key rates and low quantum bit error rates ( qbers ), are impractical in communicating with destinations without an established fibre link [ 4 ]. free - space quantum channels can overcome such limitations and reach long distances with the advent of satellite - to - ground links [ 5 - 8 ]. shorter line - of - sight free - space links have also been realized for intra - city conditions [ 2, 9 ]. however, turbulence, resulting from local fluctuations in refractive index, becomes a major challenge by adding errors and losses [ 10 ]. recently, an interest in investigating the possibility of underwater quantum channels has arisen, which could provide global secure communication channels among submersibles and boats [ 11 - 13 ]. here, we investigate the effect of turbulence on an underwater quantum channel using twisted photons in outdoor conditions. we study the effect of turbulence on transmitted qbers, and compare different qkd protocols in an underwater quantum channel showing the feasibility of high - dimensional encoding schemes. our work may open the way for secure high - dimensional quantum communication between submersibles, and provides important input for potential submersibles - to - satellite quantum communication. | arxiv:1801.10299 |
we investigate the coupling of vector mesons with nucleons to nucleon resonances in an isospin - selective vmd approach and explore the in - medium properties of vector mesons. | arxiv:nucl-th/0103059 |
modern electron linear accelerators are often designed to produce smooth bunch distributions characterized by their macroscopic ensemble - average moments. however, an increasing number of accelerator applications call for finer control over the beam distribution, e. g., by requiring specific shapes for its projection along one coordinate. ultimately, the control of the beam distribution at the single - particle level could enable new opportunities in accelerator science. this review discusses the recent progress toward controlling electron beam distributions on the " mesoscopic " scale with an emphasis on shaping the beam or introducing complex correlations required for some applications. this review emphasizes experimental and theoretical developments of electron - bunch shaping methods based on bounded external electromagnetic fields or via interactions with the self - generated velocity and radiation fields. | arxiv:2111.00520 |
we show that negative refraction in materials can occur at frequencies $ \ omega $ where the real parts of the permittivity $ \ veps ( \ omega ) $ and the permeability $ \ mu ( \ omega ) $ have different sign, and that light with such frequencies can propagate just as well as light with frequencies where they have equal sign. therefore, for negative refraction one does not need to be in the ` ` double - negative ' ' regime. we consider negative refractive index achiral materials using the drude - lorentz model and chiral materials using the drude - born - fedorov model. we find that the time - averaged poynting vector always points along the wave vector, the time - averaged energy - flux density is always positive, and the time - averaged energy density is positive ( negative ) when the refractive index is positive ( negative ). the phase velocity is negative when the real part of the refractive index is negative, and the group velocity generally changes sign several times as a function of frequency near resonance. | arxiv:2308.12019 |
we construct a concise u ( 1 ) _ x froggatt - nielsen model in which baryon triality, a discrete gauge z _ 3 symmetry, arises from u ( 1 ) _ x breaking. the proton is thus stable, however, r - parity is violated. with the proper choice of u ( 1 ) _ x charges we can obtain neutrino masses and mixings consistent with an explanation of the atmospheric and solar neutrino anomalies in terms of neutrino oscillations, with no right - handed neutrinos required. the only mass scale apart from m _ grav is m _ 3 / 2 ~ m _ soft. | arxiv:hep-ph/0610026 |
we present the technical tools needed to compute any one - loop amplitude involving external spacetime fermions in a four - dimensional heterotic string model a ` la kawai - lewellen - tye. as an example, we compute the one - loop three - point amplitude with one " photon " and two external massive fermions ( " electrons " ). as a check of our computation, we verify that the one - loop contribution to the anomalous magnetic moment vanishes if the model has spacetime supersymmetry, as required by the supersymmetric sum rules. | arxiv:hep-th/9411015 |
to reduce the latency associated with autoretrogressive llm inference, speculative decoding has emerged as a novel decoding paradigm, where future tokens are drafted and verified in parallel. however, the practical deployment of speculative decoding is hindered by its requirements for additional computational resources and fine - tuning, which limits its out - of - the - box usability. to address these challenges, we present pld +, a suite of novel algorithms developed to accelerate the inference process of llms, particularly for input - guided tasks. these tasks, which include code editing, text editing, summarization, etc., often feature outputs with substantial overlap with their inputs - an attribute pld + is designed to exploit. pld + also leverages the artifacts ( attention and hidden states ) generated during inference to accelerate inference speed. we test our approach on five input - guided tasks and through extensive experiments we find that pld + outperforms all tuning - free approaches. in the greedy setting, it even outperforms the state - of - the - art tuning - dependent approach eagle on four of the tasks. ( by a margin of upto 2. 31 in terms of avg. speedup ). our approach is tuning free, does not require any additional compute and can easily be used for accelerating inference of any llm. | arxiv:2412.01447 |
the input to the np - hard point line cover problem ( plc ) consists of a set $ p $ of $ n $ points on the plane and a positive integer $ k $, and the question is whether there exists a set of at most $ k $ lines which pass through all points in $ p $. a simple polynomial - time reduction reduces any input to one with at most $ k ^ 2 $ points. we show that this is essentially tight under standard assumptions. more precisely, unless the polynomial hierarchy collapses to its third level, there is no polynomial - time algorithm that reduces every instance $ ( p, k ) $ of plc to an equivalent instance with $ o ( k ^ { 2 - \ epsilon } ) $ points, for any $ \ epsilon > 0 $. this answers, in the negative, an open problem posed by lokshtanov ( phd thesis, 2009 ). our proof uses the machinery for deriving lower bounds on the size of kernels developed by dell and van melkebeek ( stoc 2010 ). it has two main ingredients : we first show, by reduction from vertex cover, that plc - - - conditionally - - - has no kernel of total size $ o ( k ^ { 2 - \ epsilon } ) $ bits. this does not directly imply the claimed lower bound on the number of points, since the best known polynomial - time encoding of a plc instance with $ n $ points requires $ \ omega ( n ^ { 2 } ) $ bits. to get around this we build on work of goodman et al. ( stoc 1989 ) and devise an oracle communication protocol of cost $ o ( n \ log n ) $ for plc ; its main building block is a bound of $ o ( n ^ { o ( n ) } ) $ for the order types of $ n $ points that are not necessarily in general position, and an explicit algorithm that enumerates all possible order types of n points. this protocol and the lower bound on total size together yield the stated lower bound on the number of points. while a number of essentially tight polynomial lower bounds on total sizes of kernels are known, our result is - - - to the best of our knowledge - - - the first to show a nontrivial lower bound for structural / secondary parameters. | arxiv:1307.2521 |
frequently, the design of physicochemical processes requires screening of large numbers of alternative designs with complex geometries. these geometries may result in conformal meshes which introduce stability issues, significant computational complexity, and require user - interaction for their creation. in this work, a method for simulation of heat transfer using the diffuse interface method to capture complex geometry is presented as an alternative to a conformal meshing, with analysis and comparisons given. the methods presented include automated non - iterative generation of phase fields from cad geometries and an extension of the diffuse interface method for mixed boundary conditions. simple measures of diffuse interface quality are presented and found provide predictions of performance. the method is applied to a realistic heat transfer problem and compared to the traditional conformal mesh approach. it is found to enable reasonable accuracy at an order - of - magnitude reduction in simulation time or comparable accuracy for equivalent simulation times. | arxiv:2101.06824 |
with the increasing capabilities of machine learning systems and their potential use in safety - critical systems, ensuring high - quality data is becoming increasingly important. in this paper we present a novel approach for the assurance of data quality. for this purpose, the mathematical basics are first discussed and the approach is presented using multiple examples. this results in the detection of data points with potentially harmful properties for the use in safety - critical systems. | arxiv:2307.04368 |
this paper presents the first set of fully calibrated images and associated stellar catalogs of the pre - flames survey being carried out by the eso imaging survey ( eis ) project. the primary goal of this survey is to provide the eso community with data sets from which suitable target lists can be extracted for follow - up observations with the new vlt facility flames. for this purpose 160 stellar fields have been selected for observations in b, v and i using the 8kx8k wide field imager ( wfi ) at the mpg / eso 2. 2 m telescope at la silla. these data have been used to assess the observing strategy adopted and to define suitable reduction techniques and procedures for the preparation of input catalogs for flames. the images and catalogs presented here are publicly available and can be requested from the url address ` ` http : / / www. eso. org / eis ' '. | arxiv:astro-ph/0109544 |
we present a simple solution to a question posed by candes, romberg and tao on the uniform uncertainty principle for bernoulli random matrices. more precisely, we show that a rectangular k * n random subgaussian matrix ( with k < n ) has the property that by arbitrarily extracting any m ( with m < k ) columns, the resulting submatrices are arbitrarily close to ( multiples of ) isometries of a euclidean space. we obtain the optimal estimate for m as a function of k, n and the degree of " closeness " to an isometry. we also give a short and self - contained solution of the reconstruction problem for sparse vectors. | arxiv:math/0608665 |
the vortex of iron - based superconductors is emerging as a promising platform for majorana zero mode, owing to a magic integration among intrinsic vortex winding, non - trivial band topology, strong electron - electron correlations, high - tc superconductivity and the simplification of single material. it overcomes many difficulties suffered in heterostructure - based majorana platforms, including small topological gap, interfacial contamination, lattice imperfections, and etc. isolated zero - bias peaks have been found in vortex of several iron - based superconductors. so far, studies from both experimental and theoretical aspects strongly indicate the realization of vortex majorana zero mode, with a potential to be applied to topological quantum computation. by taking fe ( te, se ) superconductor as an example, here we review original idea and research progress of majorana zero modes in this new platform. after introducing the identifications of topological band structure and real zero modes in vortex, we summarize the physics behaviors of vortex majorana zero modes systematically. firstly, relying on the behavior of the zero mode wave function and evidence of quasiparticle poisoning, we analyze the mechanism of emergence of vortex majorana zero modes. secondly, assisted with some well - established theories, we elaborate the measurements on majorana symmetry and topological nature of vortex majorana zero modes. after that, we switch from quantum physics to quantum engineering, and analyze the performance of vortex majorana zero mode under real circumstances, which may potentially benefit the exploration of practical applications in the future. this review follows the physics properties of vortex majorana zero modes, especially emphasizes the link between phenomena and mechanisms. it provides a chance to bridge the gap between the well - established theories and the newly discovered iron home of majoranas. | arxiv:2108.12850 |
it has recently been shown that the low energy dynamics of the large $ n $ gauge theory on $ s ^ 3 $ at finite temperature reduces to a one - matrix model, where the matrix is given by the holonomy of the gauge field around the euclidean time direction compactified on a circle. on the other hand, there is a prescription for constructing a closed string field theory in the temporal gauge from a given one - matrix model via loop equations. i identify the closed string field theory in the temporal gauge constructed from the above matrix model as effective closed string field theory that describes the propagations of closed strings in the radial and euclidean time directions in the bulk. then i argue that a coherent state in this string field theory describes winding string condensation, which has been expected to cause the topology change from the thermal ads geometry to the ads - schwarzschild black hole geometry. | arxiv:hep-th/0608108 |
saskatchewan polytechnic ( formerly the saskatchewan institute of applied science and technology or siast ) is saskatchewan ' s primary public post - secondary institution for technical education and skills training, recognized nationally and internationally for its expertise and innovation. through program and course registrations, saskatchewan polytechnic serves 26, 000 distinct students with programs that touch every sector of the economy. it operates campuses in moose jaw, prince albert, regina and saskatoon ; and provides a number of courses and programs through distance education. saskatchewan polytechnic maintains reciprocal arrangements with partner institutions, including : dumont technical institute, first nations university of canada, saskatchewan indian institute of technologies, university of regina, and the university of saskatchewan. = = programs = = saskatchewan polytechnic offers over 150 programs in applied / visual media, aviation, basic education, business, community / human services, engineering technology, health services, hospitality / food services, industrial / trades, natural resources, nursing, technology, recreation and tourism, and science. in addition, saskatchewan polytechnic provides training to apprentices in several trades. = = campus = = saskatchewan polytechnic comprises four campuses in saskatchewan : saskatoon ( formerly siast kelsey campus ), located on treaty 6 territory. located at idylwyld drive north and 33rd street east ( southeast corner ) in saskatoon, the campus is named for henry kelsey, a famous fur trader and explorer. the institute in saskatoon dates back to 1941 when the canadian vocational training school was established to train veterans returning from the war. the campus contains over 13 acres ( 5. 3 ha ) of instructional floor space. moose jaw ( formerly siast palliser campus ), located on treaty 4 territory. regina ( formerly siast wascana campus ), also located on treaty 4 territory. prince albert ( formerly siast woodland campus ), also located on treaty 6 territory. = = history = = the four schools that make up saskatchewan polytechnic started off as four individual schools. the moose jaw campus started off as the saskatchewan technical institute in 1959. saskatoon began as the central saskatchewan technical institute in 1963. regina began as the saskatchewan institute of applied arts and sciences in 1972. prince albert began as the northern institute of technology in 1986. on january 1, 1988, the institute act and the regional colleges act amalgamated saskatchewan ' s technical institutes, urban community colleges and the advanced technology training centre to form the saskatchewan institute of applied science and technology ( siast ). the institution was named saskatchewan polytechnic on september 24, 2014. = = scholarships = = saskatchewan polytechnic joined project hero, a scholarship program cofounded by general ( ret ' d ) rick hill | https://en.wikipedia.org/wiki/Saskatchewan_Polytechnic |
we study photoelectron angular distributions ( pads ) near the ionization threshold with a newly developed coulomb quantum - orbit strong - field approximation ( cqsfa ) theory. the cqsfa simulations present an excellent agreement with the result from time - dependent schr \ " odinger equation method. we show that the low - energy fan - shaped structure in the pads corresponds to a subcycle time - resolved holographic structure and stems from the significant influence of the coulomb potential on the phase of the forward - scattering electron trajectories, which affects different momenta and scattering angles unequally. for the first time, our work provides a direct explanation of how the fan - shaped structure is formed, based on the quantum interference of direct and forward - scattered orbits. | arxiv:1703.04123 |
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