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mutation testing can be used to assess the fault - detection capabilities of a given test suite. to this aim, two characteristics of mutation testing frameworks are of paramount importance : ( i ) they should generate mutants that are representative of real faults ; and ( ii ) they should provide a complete tool chain able to automatically generate, inject, and test the mutants. to address the first point, we recently proposed an approach using a recurrent neural network encoder - decoder architecture to learn mutants from ~ 787k faults mined from real programs. the empirical evaluation of this approach confirmed its ability to generate mutants representative of real faults. in this paper, we address the second point, presenting deepmutation, a tool wrapping our deep learning model into a fully automated tool chain able to generate, inject, and test mutants learned from real faults. video : https : / / sites. google. com / view / learning - mutation / deepmutation
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arxiv:2002.04760
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business was awarded a s $ 60m contract to design, build and operate a state - of - the - art smart city platform with citywide network connectivity for lusail city, qatar. powered by ai, machine learning and data analytics, st engineering urban solution ’ s agil smart city operating system will serve as the digital backbone of lusail. st engineering is a major player in the defence and military industries. it was ranked number 58 in the stockholm international peace research institute ' s list of the world ' s top 100 defence manufacturers in 2023. outside of singapore, it has sold defence products to over 100 countries, including united states, united kingdom, indonesia, philippines, united arab emirates, brazil, sweden, india, thailand and finland. st engineering do not design, produce or sell anti - personnel mines, cluster munitions, white phosphorus munitions and its related key components. on december 12, 2024, st engineering signed a strategic agreement with kazakhstan paramount engineering to set up in - country production capability for a new 8x8 armored vehicle. st engineering expanded to the united states in 2001, locating its u. s. headquarters in herndon, virginia. it now operates in 52 cities across 21 states. it was known as vt systems ( vts ; formerly known as vision technologies systems ) until 1 july 2019, when vts was changed to st engineering north america as part of the group ’ s brand harmonization exercise in 2018. = = core capabilities = = st engineering ' s businesses span across the aerospace, smart city, defence and public security sectors. = = = aerospace = = = st engineering ' s aerospace arm provides aviation asset management to commercial airlines, airfreight operators and military operators. it is the world ' s largest airframe maintenance, repair, and operations ( mro ) company, and one of the few with in - house engineering design and development capabilities. on top of mro capabilities, st engineering also has expertise as an oem specialising in engine nacelle and composite panels. it is the only company in the world offering airbus freighter conversions using oem data. st engineering is a major investor in skyports to provide drone services for singapore ’ s public utilities board. = = = smart city = = = st engineering ' s capabilities for smart city addresses the connectivity, mobility, security, infrastructure and environmental needs of cities. its products span over rail and road, autonomous and electric vehicles, mobility payment systems, building access and security systems, as well as iot products for lighting, water and energy
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https://en.wikipedia.org/wiki/ST_Engineering
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in this paper, we obtain the berry - esseen bound for multivariate normal approximation for the polyak - ruppert averaged iterates of the linear stochastic approximation ( lsa ) algorithm with decreasing step size. moreover, we prove the non - asymptotic validity of the confidence intervals for parameter estimation with lsa based on multiplier bootstrap. this procedure updates the lsa estimate together with a set of randomly perturbed lsa estimates upon the arrival of subsequent observations. we illustrate our findings in the setting of temporal difference learning with linear function approximation.
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arxiv:2405.16644
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we study bayesian optimization ( bo ) in high - dimensional and non - stationary scenarios. existing algorithms for such scenarios typically require extensive hyperparameter tuning, which limits their practical effectiveness. we propose a framework, called ballet, which adaptively filters for a high - confidence region of interest ( roi ) as a superlevel - set of a nonparametric probabilistic model such as a gaussian process ( gp ). our approach is easy to tune, and is able to focus on local region of the optimization space that can be tackled by existing bo methods. the key idea is to use two probabilistic models : a coarse gp to identify the roi, and a localized gp for optimization within the roi. we show theoretically that ballet can efficiently shrink the search space, and can exhibit a tighter regret bound than standard bo without roi filtering. we demonstrate empirically the effectiveness of ballet on both synthetic and real - world optimization tasks.
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arxiv:2307.13371
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sentiment analysis ( sa ) in bengali is challenging due to this indo - aryan language ' s highly inflected properties with more than 160 different inflected forms for verbs and 36 different forms for noun and 24 different forms for pronouns. the lack of standard labeled datasets in the bengali domain makes the task of sa even harder. in this paper, we present manually tagged 2 - class and 3 - class sa datasets in bengali. we also demonstrate that the multi - lingual bert model with relevant extensions can be trained via the approach of transfer learning over those novel datasets to improve the state - of - the - art performance in sentiment classification tasks. this deep learning model achieves an accuracy of 71 \ % for 2 - class sentiment classification compared to the current state - of - the - art accuracy of 68 \ %. we also present the very first bengali sa classifier for the 3 - class manually tagged dataset, and our proposed model achieves an accuracy of 60 \ %. we further use this model to analyze the sentiment of public comments in the online daily newspaper. our analysis shows that people post negative comments for political or sports news more often, while the religious article comments represent positive sentiment. the dataset and code is publicly available at https : / / github. com / khondokerislam / bengali \ _ sentiment.
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arxiv:2012.07538
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recent results in the search for supersymmetry in pp collisions at sqrt ( s ) = 7 tev and sqrt ( s ) = 8 tev by the atlas and cms experiments at the lhc are reviewed. after discussing features of inclusive analyses and the presentation of results, emphasis will be put on searches for the third generation squarks, on searches for gauginos, and on possible ways supersymmetry could escape the present analyses.
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arxiv:1211.3887
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we prove the existence of a quillen flat model structure in the category of unbounded complexes of h - unitary modules over a nonunital ring ( or a $ k $ - algebra, with $ k $ a field ). this model structure provides a natural framework where a morita - invariant homological algebra for these nonunital rings can be developed. and it is compatible with the usual tensor product of complexes. the waldhausen category associated to its cofibrations allows to develop a morita invariant excisive higher $ k $ - theory for nonunital algebras.
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arxiv:0906.4735
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understanding the formation and evolution of young star clusters requires quantitative statistical measures of their structure. we investigate the structures of observed and modelled star - forming clusters. by considering the different evolutionary classes in the observations and the temporal evolution in models of gravoturbulent fragmentation, we study the temporal evolution of the cluster structures. we apply different statistical methods, in particular the normalised mean correlation length and the minimum spanning tree technique. we refine the normalisation of the clustering parameters by defining the area using the normalised convex hull of the objects and investigate the effect of two - dimensional projection of three - dimensional clusters. we introduce a new measure $ \ xi $ for the elongation of a cluster. it is defined as the ratio of the cluster radius determined by an enclosing circle to the cluster radius derived from the normalised convex hull. the mean separation of young stars increases with the evolutionary class, reflecting the expansion of the cluster. the clustering parameters of the model clusters correspond in many cases well to those from observed ones, especially when the $ \ xi $ values are similar. no correlation of the clustering parameters with the turbulent environment of the molecular cloud is found, indicating that possible influences of the environment on the clustering behaviour are quickly smoothed out by the stellar velocity dispersion. the temporal evolution of the clustering parameters shows that the star cluster builds up from several subclusters and evolves to a more centrally concentrated cluster, while the cluster expands slower than new stars are formed.
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arxiv:astro-ph/0511448
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we present a unified algebraic bethe ansatz for open vertex models which are associated with the non - exceptional $ a ^ { ( 2 ) } _ { 2n }, a ^ { ( 2 ) } _ { 2n - 1 }, b ^ { ( 1 ) } _ n, c ^ { ( 1 ) } _ n, d ^ { ( 1 ) } _ { n } $ lie algebras. by the method, we solve these models with the trivial k matrix and find that our results agree with that obtained by analytical bethe ansatz. we also solve the $ b ^ { ( 1 ) } _ n, c ^ { ( 1 ) } _ n, d ^ { ( 1 ) } _ { n } $ models with some non - trivial diagonal k - matrices ( one free parameter case ) by the algebraic bethe ansatz.
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arxiv:hep-th/0611127
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spectroscopic techniques based on core - level excitations provide powerful tools for probing molecular and electronic structures with high spatial resolution. however, accurately calculating spectral features at the l or m edges is challenging due to the significant influence of spin - orbit and multiplet effects. while scalar - relativistic effects can be incorporated at minimal computational cost, accounting for spin - orbit interactions requires more complex computational frameworks. in this work, we develop and apply the state - interaction approach, incorporating relativistic effects using the zora - kohn - sham hamiltonian, to simulate near - edge soft x - ray absorption spectra for closed - shell transition metal complexes. the computed spin - orbit splittings closely match those obtained from more rigorous methods. this approach provides a practical and cost - effective alternative to more rigorous two - component methods, making it particularly valuable for large - scale calculations and applications such as resonant inelastic x - ray scattering simulations, where capturing a large number of excited states is essential.
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arxiv:2503.15462
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we have shown previously that a merger of marginally outer trapped surfaces ( motss ) occurs in a binary black hole merger and that there is a continuous sequence of motss which connects the initial two black holes to the final one. in this paper, we confirm this scenario numerically and we detail further improvements in the numerical methods for locating motss. with these improvements, we confirm the merger scenario and demonstrate the existence of self - intersecting motss formed in the immediate aftermath of the merger. these results will allow us to track physical quantities across the non - linear merger process and to potentially infer properties of the merger from gravitational wave observations.
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arxiv:1907.00683
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snowman is the consensus protocol run by blockchains on avalanche. recent work established a rigorous proof of probabilistic consistency for snowman in the \ emph { synchronous } setting, under the simplifying assumption that correct processes execute sampling rounds in ` lockstep '. in this paper, we describe a modification of the protocol that ensures consistency in the \ emph { partially synchronous } setting, and when correct processes carry out successive sampling rounds at their own speed, with the time between sampling rounds determined by local message delays.
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arxiv:2501.15904
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in this paper, we consider a special class of nonlinear optimal control problems, where the control variables are box - constrained and the objective functional is strongly convex corresponding to control variables and separable with respect to the state variables and control variables. we convert solving the original nonlinear problem into solving a sequence of constrained linear - quadratic optimal control problems by quasilinearization method. in order to solve each linear - quadratic problem efficiently we turn to study its dual problem. we formulate dual problem by the scheme of fenchel duality, the strong duality property and the saddle point property corresponding to primal and dual problem are also proved, which together ensure that solving dual problem is effective. thus solving the sequence of control constrained linear - quadratic optimal control problems obtained by quasilinearization technique is substituted by solving the sequence of their dual problem. we solve the sequence of dual problem and obtain the solution to primal control constrained linear - quadratic problem by the saddle point property. furthermore, the fact that solution to each subproblem finally converges to the solution to the optimality conditions of original nonlinear problem is also proved. after that we carry out numerical experiments using present approach, for each subproblem we formulate the discretized primal and dual problem by euler discretization scheme in our experiments. efficiency of the present method is validated by numerical results.
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arxiv:2201.07483
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the flow of power law fluids, which include shear thinning and shear thickening as well as newtonian as a special case, in networks of interconnected elastic tubes is investigated using a residual based pore scale network modeling method with the employment of newly derived formulae. two relations describing the mechanical interaction between the local pressure and local cross sectional area in distensible tubes of elastic nature are considered in the derivation of these formulae. the model can be used to describe shear dependent flows of mainly viscous nature. the behavior of the proposed model is vindicated by several tests in a number of special and limiting cases where the results can be verified quantitatively or qualitatively. the model, which is the first of its kind, incorporates more than one major non - linearity corresponding to the fluid rheology and conduit mechanical properties, that is non - newtonian effects and tube distensibility. the formulation, implementation and performance indicate that the model enjoys certain advantages over the existing models such as being exact within the restricting assumptions on which the model is based, easy implementation, low computational costs, reliability and smooth convergence. the proposed model can therefore be used as an alternative to the existing newtonian distensible models ; moreover it stretches the capabilities of the existing modeling approaches to reach non - newtonian rheologies.
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arxiv:1405.6325
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we have found an exact phase diagram of the potts model with next nearest neighbor interactions on the bethe lattice of order two. the diagram consists of five phases : ferromagnetic, paramagnetic, modulated, antiphase and paramodulated, all meeting at the lifshitz point i. e. $ p = 1 / 3 $. we report on a new phase which we denote as paramodulated, found at low temperatures and characterized by 2 - periodic points of an one dimensional dynamical system lying inside the modulated phase. such a phase, inherent in the potts model has no analogues in the ising setting.
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arxiv:0803.2558
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all mobile devices are energy - constrained. they use batteries that allows using the device for a limited amount of time. in general, energy attacks on mobile devices are denial of service ( dos ) type of attacks. while previous studies have analyzed the energy attacks in servers, no existing work has analyzed the energy attacks on mobile devices. as such, in this paper, we present the first systematic study on how to exploit the energy attacks on smartphones. in particular, we explore energy attacks from the following aspect : hardware components, software resources, and network communications through the design and implementation of concrete malicious apps, and malicious web pages. we quantitatively show how quickly we can drain the battery through each individual attack, as well as their combinations. finally, we believe energy exploit will be a practical attack vector and mobile users should be aware of this type of attacks.
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arxiv:1704.04464
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we show that an alkali atom with a tripod electronic structure can yield rich electromagnetically induced transparency phenomena even at room temperature. in particular we introduce double - double electromagnetically induced transparency wherein signal and probe fields each have two transparency windows. their group velocities can be matched in either the first or second pair of transparency windows. moreover signal and probe fields can each experience coherent gain in the second transparency windows. we explain using a semi - classical - dressed - picture to connect the tripod electronic structure to a double - \ lambda \ scheme.
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arxiv:1310.3318
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as covid - 19 pandemic progresses, severe flu seasons may happen alongside an increase in cases in cases and death of covid - 19, causing severe burdens on health care resources and public safety. a consequence of a twindemic may be a mixture of two different infections in the same person at the same time, " flurona ". admist the raising trend of " flurona ", forecasting both influenza outbreaks and covid - 19 waves in a timely manner is more urgent than ever, as accurate joint real - time tracking of the twindemic aids health organizations and policymakers in adequate preparation and decision making. under the current pandemic, state - of - art influenza and covid - 19 forecasting models carry valuable domain information but face shortcomings under current complex disease dynamics, such as similarities in symptoms and public healthcare seeking patterns of the two diseases. inspired by the inner - connection between influenza and covid - 19 activities, we propose argox - joint - ensemble which allows us to combine historical influenza and covid - 19 disease forecasting models to a new ensemble framework that handles scenarios where flu and covid co - exist. our framework is able to emphasize learning from covid - related or influenza signals, through a winner - takes - all ensemble fashion. moreover, our experiments demonstrate that our approach is successful in adapting past influenza forecasting models to the current pandemic, while improving upon previous covid - 19 forecasting models, by steadily outperforming alternative benchmark methods, and remaining competitive with publicly available models.
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arxiv:2202.02621
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we consider the behaviour of a continuous super - brownian motion catalysed by a random medium with infinite overall density under the hydrodynamic scaling of mass, time, and space. we show that, in supercritical dimensions, the scaled process converges to a macroscopic heat flow, and the appropriately rescaled random fluctuations around this macroscopic flow are asymptotically bounded, in the sense of log - laplace transforms, by generalised stable ornstein - uhlenbeck processes. the most interesting new effect we observe is the occurrence of an index - jump from a ' gaussian ' situation to stable fluctuations of index 1 + gamma, where gamma is an index associated to the medium.
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arxiv:math/0508368
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we discuss how the nonequilibrium process of pion production within the zubarev approach of the nonequilibrium statistical operator leads to a theoretical foundation for the appearance of a nonequilibrium pion chemical potential for the pion distribution function for which there is experimental evidence in experiments at the cern lhc.
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arxiv:2004.05401
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there are indications that some high temperature unconventional superconductors have a " complex " d - wave order parameter ( with an admixture of s - wave ) leading to nonzero energy gap. since the coherence length is short and the fermi energy is relatively small the quasiclassical approach is inapplicable and the more complicated bogoliubov - degennes equations should be used to investigate the excitation spectrum of such a material in a magneric field. it turns out that equations for the gapped chiral d - wave superconductor, simplify considerably and is the basis for any superconductor of that type with a sufficiently large gap. the spectrum of core excitations of the abrikosov vortex in an anisotropic 3d sample exhibits several features. unlike in conventional and gapless superconductors the core has a single excitation mode of order energy gap for each value of momentum along the field. this has a large impact on thermal transport and vortex dynamics.
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arxiv:1306.2749
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radiation therapy is a critical component of cancer treatment. however, the delivery of radiation poses inherent challenges, particularly in minimizing radiation exposure to healthy organs surrounding the tumor site. one significant contributing factor to this challenge is the patient ' s respiration, which introduces uncertainties in the precise targeting of radiation. managing these uncertainties during radiotherapy is essential to ensure effective tumor treatment while minimizing the adverse effects on healthy tissues. this research addresses the crucial objective of achieving a balanced dose distribution during radiation therapy under conditions of respiration uncertainty. to tackle this issue, we begin by developing a motion uncertainty model employing probability density functions that characterize breathing motion patterns. this model forms the foundation for our efforts to optimize radiation dose delivery. next, we employ three bio - inspired optimization techniques : cuckoo search optimization ( cso ), flower pollination algorithm ( fpa ), and bat search optimization ( bso ). our research evaluates the dose distribution in gy on both the tumor and healthy organs by applying these bio - inspired optimization methods to identify the most effective approach. this research ultimately aids in refining the strategies used in radiation therapy planning under the challenging conditions posed by respiration uncertainty. through the application of bio - inspired optimization techniques and a comprehensive evaluation of dose distribution, we seek to improve the precision and safety of radiation therapy, thereby advancing cancer treatment outcomes.
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arxiv:2309.15448
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in the realm of self - supervised learning ( ssl ), masked image modeling ( mim ) has gained popularity alongside contrastive learning methods. mim involves reconstructing masked regions of input images using their unmasked portions. a notable subset of mim methodologies employs discrete tokens as the reconstruction target, but the theoretical underpinnings of this choice remain underexplored. in this paper, we explore the role of these discrete tokens, aiming to unravel their benefits and limitations. building upon the connection between mim and contrastive learning, we provide a comprehensive theoretical understanding on how discrete tokenization affects the model ' s generalization capabilities. furthermore, we propose a novel metric named tcas, which is specifically designed to assess the effectiveness of discrete tokens within the mim framework. inspired by this metric, we contribute an innovative tokenizer design and propose a corresponding mim method named clustermim. it demonstrates superior performance on a variety of benchmark datasets and vit backbones. code is available at https : / / github. com / pku - ml / clustermim.
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arxiv:2407.09087
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this paper is concerned with the proof of existence and numerical approximation of large - data global - in - time young measure solutions to initial - boundary - value problems for multidimensional nonlinear parabolic systems of forward - backward type of the form $ \ partial _ t u - \ mbox { div } ( a ( du ) ) + bu = f $, where $ b \ in \ mathbb { r } ^ { m \ times m } $, $ bv \ cdot v \ geq 0 $ for all $ v \ in \ mathbb { r } ^ m $, $ f $ is an $ m $ - component vector - function defined on a bounded open lipschitz domain $ \ omega \ subset \ mathbb { r } ^ n $, and $ a $ is a locally lipschitz mapping of the form $ a ( a ) = k ( a ) a $, where $ k \, : \, \ mathbb { r } ^ { m \ times n } \ rightarrow \ mathbb { r } $. the function $ a $ may have a nonstandard growth rate, in the sense that it is permitted to have unequal lower and upper growth rates. furthermore, $ a $ is not assumed to be monotone, nor is it assumed to be the gradient of a potential. problems of this type arise in mathematical models of the atmospheric boundary layer and fall beyond the scope of monotone operator theory. we develop a numerical algorithm for the approximate solution of problems in this class, and we prove the convergence of the algorithm to a young measure solution of the system under consideration.
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arxiv:1902.10187
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the accretion - induced collapse ( aic ) of a white dwarf to form a neutron star can leave behind a rotationally supported disk with mass of up to ~ 0. 1 m _ sun. the disk is initially composed of free nucleons but as it accretes and spreads to larger radii, the free nucleons recombine to form helium, releasing sufficient energy to unbind the remaining disk. most of the ejected mass fuses to form ni56 and other iron group elements. we present spherically symmetric radiative transfer calculations of the transient powered by the radioactive heating of this ejecta. for an ejecta mass of 1e - 2 m _ sun ( 3e - 3 m _ sun ), the lightcurve peaks after < ~ 1 day with a peak bolometric luminosity ~ 2e41 erg / s ( ~ 5e40 erg / s ), i. e., a " kilonova " ; the decay time is ~ 4 ( 2 ) days. overall, the spectra redden with time reaching u - v ~ 4 after ~ 1 day ; the optical colors ( b - v ) are, however, somewhat blue. near the peak in the lightcurve, the spectra are dominated by doppler broadened nickel features, with no distinct spectral lines present. at ~ 3 - 5 days, strong calcium lines are present in the infrared, although the calcium mass fraction is only ~ 1e - 4. 5. if rotationally supported disks are a common byproduct of aic, current and upcoming transient surveys such as the palomar transient factory should detect a few aic per year for an aic rate of ~ 1e - 2 of the type ia rate. we discuss ways of distinguishing aic from other rapid, faint transients, including. ia ' s and the ejecta from binary neutron star mergers.
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arxiv:1005.1081
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in this paper, we consider a point to point full duplex ( fd ) mimo communication system. we assume that each node is equipped with an arbitrary number of antennas which can be used for transmission or reception. with fd radios, bidirectional information exchange between two nodes can be achieved at the same time. in this paper we design bidirectional link selection schemes by selecting a pair of transmit and receive antenna at both ends for communications in each direction to maximize the weighted sum rate or minimize the weighted sum symbol error rate ( ser ). the optimal selection schemes require exhaustive search, so they are highly complex. to tackle this problem, we propose a serial - max selection algorithm, which approaches the exhaustive search methods with much lower complexity. in the serial - max method, the antenna pairs with maximum " obtainable sinr " at both ends are selected in a two - step serial way. the performance of the proposed serial - max method is analyzed, and the closed - form expressions of the average weighted sum rate and the weighted sum ser are derived. the analysis is validated by simulations. both analytical and simulation results show that as the number of antennas increases, the serial - max method approaches the performance of the exhaustive - search schemes in terms of sum rate and sum ser.
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arxiv:1503.07604
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we report the discovery of a planet by the microlensing method, ogle - 2012 - blg - 0724lb. although the duration of the planetary signal for this event was one of the shortest seen for a planetary event, the anomaly was well covered thanks to high cadence observations taken by the survey groups ogle and moa. by analyzing the light curve, this planetary system is found to have a mass ratio $ q = ( 1. 58 \ pm0. 15 ) \ times10 ^ { - 3 } $. by conducting a bayesian analysis, we estimate that the host star is an m - dwarf star with a mass of $ m _ { \ rm l } = 0. 29 _ { - 0. 16 } ^ { + 0. 33 } \ m _ { \ odot } $ located at $ d _ { \ rm l } = 6. 7 _ { - 1. 2 } ^ { + 1. 1 } \ { \ rm kpc } $ away from the earth and the companion ' s mass is $ m _ { \ rm p } = 0. 47 _ { - 0. 26 } ^ { + 0. 54 } \ m _ { \ rm jup } $. the projected planet - host separation is $ a _ { \ perp } = 1. 6 _ { - 0. 3 } ^ { + 0. 4 } \ { \ rm au } $. because the lens - source relative proper motion is relatively high, future high resolution images would detect the lens host star and determine the lens properties uniquely. this system is likely a saturn - mass exoplanet around an m - dwarf and such systems are commonly detected by gravitational microlensing. this adds an another example of a possible pileup of sub - jupiters $ ( 0. 2 < m _ { \ rm p } / m _ { \ rm jup } < 1 ) $ in contrast to a lack of jupiters ( $ \ sim 1 - 2 \ m _ { \ rm jup } $ ) around m - dwarfs, supporting the prediction by core accretion models that jupiter - mass or more massive planets are unlikely to form around m - dwarfs.
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arxiv:1604.05463
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we consider a strategic game, where players submit jobs to a machine that executes all jobs in a way that minimizes energy while respecting the given deadlines. the energy consumption is then charged to the players in some way. each player wants to minimize the sum of that charge and of their job ' s deadline multiplied by a priority weight. two charging schemes are studied, the proportional cost share which does not always admit pure nash equilibria, and the marginal cost share, which does always admit pure nash equilibria, at the price of overcharging by a constant factor.
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arxiv:1504.03586
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many modern data analysis algorithms either assume that or are considerably more efficient if the distances between the data points satisfy a metric. these algorithms include metric learning, clustering, and dimensionality reduction. because real data sets are noisy, the similarity measures often fail to satisfy a metric. for this reason, gilbert and jain [ 11 ] and fan, et al. [ 8 ] introduce the closely related problems of $ \ textit { sparse metric repair } $ and $ \ textit { metric violation distance } $. the goal of each problem is to repair as few distances as possible to ensure that the distances between the data points satisfy a metric. we generalize these problems so as to no longer require all the distances between the data points. that is, we consider a weighted graph $ g $ with corrupted weights w and our goal is to find the smallest number of modifications to the weights so that the resulting weighted graph distances satisfy a metric. this problem is a natural generalization of the sparse metric repair problem and is more flexible as it takes into account different relationships amongst the input data points. as in previous work, we distinguish amongst the types of repairs permitted ( decrease, increase, and general repairs ). we focus on the increase and general versions and establish hardness results and show the inherent combinatorial structure of the problem. we then show that if we restrict to the case when $ g $ is a chordal graph, then the problem is fixed parameter tractable. we also present several classes of approximation algorithms. these include and improve upon previous metric repair algorithms for the special case when $ g = k _ n $
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arxiv:1807.07619
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we study entanglement entropy after a double local quench in two - dimensional conformal field theories ( cfts ), with any central charge $ c > 1 $. in the holographic cft, such a state with double - excitation is dual to an ads space with two massive particles introduced from the boundary. we show that the growth after the double local excitations cannot be given by the sum of two local quenches but with an additional negative term. this negative contribution can be naturally interpreted as due to the attractive force of gravity. in cft side, this evaluation of the entanglement entropy is accomplished by a special limit of 6 - point functions, where we employed the fusion matrix approach for multi - point conformal blocks developed in arxiv : 1905. 02191.
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arxiv:1908.03351
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a simple sparse coding mechanism appears in the sensory systems of several organisms : to a coarse approximation, an input $ x \ in \ r ^ d $ is mapped to much higher dimension $ m \ gg d $ by a random linear transformation, and is then sparsified by a winner - take - all process in which only the positions of the top $ k $ values are retained, yielding a $ k $ - sparse vector $ z \ in \ { 0, 1 \ } ^ m $. we study the benefits of this representation for subsequent learning. we first show a universal approximation property, that arbitrary continuous functions of $ x $ are well approximated by linear functions of $ z $, provided $ m $ is large enough. this can be interpreted as saying that $ z $ unpacks the information in $ x $ and makes it more readily accessible. the linear functions can be specified explicitly and are easy to learn, and we give bounds on how large $ m $ needs to be as a function of the input dimension $ d $ and the smoothness of the target function. next, we consider whether the representation is adaptive to manifold structure in the input space. this is highly dependent on the specific method of sparsification : we show that adaptivity is not obtained under the winner - take - all mechanism, but does hold under a slight variant. finally we consider mappings to the representation space that are random but are attuned to the data distribution, and we give favorable approximation bounds in this setting.
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arxiv:2006.03741
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we prove the equivalence between the simplicial orlicz cohomology and the orlicz - de rham cohomology in the case of lie groups. since the first one is a quasi - isometry invariant for uniformly contractible simplicial complexes with bounded geometry, we obtain the invariance of the second one in the case of contractible lie groups. we also define the orlicz cohomology of a gromov - hyperbolic space relative to a point on its boundary at infinity, for which the same results are true.
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arxiv:2006.09629
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this article presents a novel scheduling approach to minimise the energy consumption of a machine during its idle periods. in the scheduling domain, it is common to model the behaviour of the machine by defining a small set of machine modes, e. g. " on ", " off " and " stand - by ". then the transitions between the modes are represented by a static transition graph. in this paper, we argue that this type of model might be too restrictive for some types of machines ( e. g. the furnaces ). for such machines, we propose to employ the complete time - domain dynamics and integrate it into an idle energy function. this way, the scheduling algorithm can exploit the full knowledge about the machine dynamics with minimised energy consumption encapsulated in this function. in this paper, we study a scheduling problem, where the tasks characterised by release times and deadlines are scheduled in the given order such that the idle energy consumption of the machine is minimised. we show that this problem can be solved in polynomial time whenever the idle energy function is concave. to highlight the practical applicability, we analyse a heat - intensive system employing a steel - hardening furnace. we derive an energy optimal control law, and the corresponding idle energy function, for the bilinear system model approximating the dynamics of the furnace ( and possibly other heat - intensive systems ). further, we prove that the idle energy function is, indeed, concave in this case. therefore, the proposed scheduling algorithm can be used. numerical experiments show that by using our approach, combining both the optimal control and optimal scheduling, higher energy savings can be achieved, compared to the state - of - the - art scheduling approaches.
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arxiv:1910.07501
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we establish the short - time existence of the ricci flow on surfaces with a finite number of conic points, all with cone angle between 0 and $ 2 \ pi $, where the cone angles remain fixed or change in some smooth prescribed way. for the angle - preserving flow we prove long - time existence and convergence. when the troyanov angle condition is satisfied ( equivalently, when the data is logarithmically k - stable ), the flow converges to the unique constant curvature metric with the given cone angles ; if this condition is not satisfied, the flow converges subsequentially to a soliton. this is the one - dimensional version of the hamilton - - tian conjecture.
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arxiv:1306.6688
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we discuss the folklore construction of the gray tensor product of 2 - categories as obtained by factoring the map from the funny tensor product to the cartesian product. we show that this factorisation can be obtained without using a concrete presentation of the gray tensor product, but merely its defining universal property, and use it to give another proof that the gray tensor product forms part of a symmetric monoidal structure. the main technical tool is a method of producing new algebra structures over lawvere 2 - theories from old ones via a factorisation system.
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arxiv:1508.07789
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we generalize and prove a result which was first shown by zippin, and was explicitly formulated by benyamini.
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arxiv:1705.10663
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for any root system corresponding to a semisimple simply - laced lie algebra a logarithmic cft is constructed. characters of irreducible representations were calculated in terms of theta functions.
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arxiv:1002.5047
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telemedicine applications have recently received substantial potential and interest, especially after the covid - 19 pandemic. remote experience will help people get their complex surgery done or transfer knowledge to local surgeons, without the need to travel abroad. even with breakthrough improvements in internet speeds, the delay in video streaming is still a hurdle in telemedicine applications. this imposes using image compression and region of interest ( roi ) techniques to reduce the data size and transmission needs. this paper proposes a deep reinforcement learning ( drl ) model that intelligently adapts the roi size and non - roi quality depending on the estimated throughput. the delay and structural similarity index measure ( ssim ) comparison are used to assess the drl model. the comparison findings and the practical application reveal that drl is capable of reducing the delay by 13 % and keeping the overall quality in an acceptable range. since the latency has been significantly reduced, these findings are a valuable enhancement to telemedicine applications.
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arxiv:2310.05099
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calibration is a basic property for prediction systems, and algorithms for achieving it are well - studied in both statistics and machine learning. in many applications, however, the predictions are used to make decisions that select which observations are made. this makes calibration difficult, as adjusting predictions to achieve calibration changes future data. we focus on click - through - rate ( ctr ) prediction for search ad auctions. here, ctr predictions are used by an auction that determines which ads are shown, and we want to maximize the value generated by the auction. we show that certain natural notions of calibration can be impossible to achieve, depending on the details of the auction. we also show that it can be impossible to maximize auction efficiency while using calibrated predictions. finally, we give conditions under which calibration is achievable and simultaneously maximizes auction efficiency : roughly speaking, bids and queries must not contain information about ctrs that is not already captured by the predictions.
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arxiv:1211.3955
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for the kdv equation with box type initial data, the interaction between a trial soliton and large - scale dispersive mean flow is studied theoretically and numerically. the pure box initial value can cause rarefaction wave and dispersive shock wave, and can create an area of soliton train. the key to the interaction of soliton and mean flow is that the dynamic evolutions of the mean flow and the local soliton can be described by the same modulation system. the soliton modulation system is derived from the degenerations of the two - genus whitham modulation system. considering the influence of rarefaction wave, dispersive shock wave and soliton train on the trial soliton, in the framework of whitham modulation theory, the equation describing the soliton trajectory and the changes in amplitude and phase shift are given explicitly. the predicted results are compared with the numerical simulations, which verifies the corrections of the theoretical analysis. the exotic interaction phenomena between soliton and mean flow found in this work have broad applications to shallow water soliton propagations and real soliton experiments in fluid dynamics.
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arxiv:2405.20826
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federated learning ( fl ) enables clients to collaborate with a server to train a machine learning model. to ensure privacy, the server performs secure aggregation of updates from the clients. unfortunately, this prevents verification of the well - formedness ( integrity ) of the updates as the updates are masked. consequently, malformed updates designed to poison the model can be injected without detection. in this paper, we formalize the problem of ensuring \ textit { both } update privacy and integrity in fl and present a new system, \ textsf { eiffel }, that enables secure aggregation of \ textit { verified } updates. \ textsf { eiffel } is a general framework that can enforce \ textit { arbitrary } integrity checks and remove malformed updates from the aggregate, without violating privacy. our empirical evaluation demonstrates the practicality of \ textsf { eiffel }. for instance, with $ 100 $ clients and $ 10 \ % $ poisoning, \ textsf { eiffel } can train an mnist classification model to the same accuracy as that of a non - poisoned federated learner in just $ 2. 4s $ per iteration.
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arxiv:2112.12727
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this paper critically examines existing modes of participation in design practice and machine learning. cautioning against ' participation - washing ', it suggests that the ml community must become attuned to possibly exploitative and extractive forms of community involvement and shift away from the prerogatives of context - independent scalability.
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arxiv:2007.02423
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in reply to the criticism made by mielke in the pereceding comment [ phys. rev. d69 ( 2004 ) 128501 ] on our recent paper, we once again explicitly demonstrate the inconsistency of the coupling of a dirac field to gravitation in the teleparallel equivalent of general relativity. moreover, we stress that the mentioned inconsistency is generic for { \ it all } sources with spin and is by no means restricted to the dirac field. in this sense the $ sl ( 4, r ) $ - covariant generalization of the spinor fields in the teleparallel gravity theory is irrelevant to the inconsistency problem.
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arxiv:gr-qc/0406015
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it is well known that the similar universal behavior of infinite - size ( bulk ) systems of different nature requires the same basic conditions : space dimensionality ; number components of order parameter ; the type ( short - or long - range ) of the intermolecular interaction ; symmetry of the fluctuation part of thermodynamical potential. basic conditions of similar universal behavior of confined systems needs the same supplementary conditions such as the number of monolayers for a system confinement ; low crossover dimensionality, i. e., geometric form of restricted volume ; boundary conditions on limiting surfaces ; physical properties under consideration. this review paper is aimed at studying all these conditions of similar universal behavior for diffusion processes in confined liquid systems. special attention was paid to the effects of spatial dispersion and low crossover dimensionality. this allowed us to receive receiving correct nonzero expressions for the diffusion coefficient at the critical point and to take into account the specific geometric form of the confined liquid volume. the problem of 3d \ leftrightarrow 2d dimensional crossover was analyzed. to receive a smooth crossover for critical exponents, the kawasaki - like approach from the theory of mode coupling in critical dynamics was proposed. this ensured a good agreement between data of computer experiment and theoretical calculations of the size dependence of the critical temperature t _ { c } ( h ) of water in slitlike pores. the width of the quasi - elastic scattering peak of slow neutrons near the structural phase transition in the aquatic suspensions of plasmatic membranes ( mesostructures with the typical thickness up to 10 nm ) was studied.
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arxiv:1307.2013
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let $ s $ and $ t $ be local rings with common residue field $ k $, let $ r $ be the fiber product $ s \ times _ k t $, and let $ m $ be an $ s $ - module. the poincar \ ' e series $ p ^ r _ m $ of $ m $ has been expressed in terms of $ p ^ s _ m $, $ p ^ s _ k $ and $ p ^ t _ k $ by kostrikin and shafarevich, and by dress and kr \ " amer. here, an explicit minimal resolution, as well as theorems on the structure of $ \ ext _ r ( k, k ) $ and $ \ ext _ r ( m, k ) $ are given that illuminate these equalities. structure theorems for the cohomology modules of fiber products of modules are also given. as an application of these results, we compute the depth of cohomology modules over a fiber product.
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arxiv:0704.3631
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since the training data of the target model is not available in the black - box substitute attack, most recent schemes utilize gans to generate data for training the substitute model. however, these gans - based schemes suffer from low training efficiency as the generator needs to be retrained for each target model during the substitute training process, as well as low generation quality. to overcome these limitations, we consider utilizing the diffusion model to generate data, and propose a novel data - free substitute attack scheme based on the stable diffusion ( sd ) to improve the efficiency and accuracy of substitute training. despite the data generated by the sd exhibiting high quality, it presents a different distribution of domains and a large variation of positive and negative samples for the target model. for this problem, we propose latent code augmentation ( lca ) to facilitate sd in generating data that aligns with the data distribution of the target model. specifically, we augment the latent codes of the inferred member data with lca and use them as guidance for sd. with the guidance of lca, the data generated by the sd not only meets the discriminative criteria of the target model but also exhibits high diversity. by utilizing this data, it is possible to train the substitute model that closely resembles the target model more efficiently. extensive experiments demonstrate that our lca achieves higher attack success rates and requires fewer query budgets compared to gans - based schemes for different target models. our codes are available at \ url { https : / / github. com / lzhmeng / lca }.
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arxiv:2307.12872
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we revisit the question of predicting both hodge numbers $ h ^ { 1, 1 } $ and $ h ^ { 2, 1 } $ of complete intersection calabi - yau ( cicy ) 3 - folds using machine learning ( ml ), considering both the old and new datasets built respectively by candelas - dale - lutken - schimmrigk / green - h \ " ubsch - lutken and by anderson - gao - gray - lee. in real world applications, implementing a ml system rarely reduces to feed the brute data to the algorithm. instead, the typical workflow starts with an exploratory data analysis ( eda ) which aims at understanding better the input data and finding an optimal representation. it is followed by the design of a validation procedure and a baseline model. finally, several ml models are compared and combined, often involving neural networks with a topology more complicated than the sequential models typically used in physics. by following this procedure, we improve the accuracy of ml computations for hodge numbers with respect to the existing literature. first, we obtain 97 % ( resp. 99 % ) accuracy for $ h ^ { 1, 1 } $ using a neural network inspired by the inception model for the old dataset, using only 30 % ( resp. 70 % ) of the data for training. for the new one, a simple linear regression leads to almost 100 % accuracy with 30 % of the data for training. the computation of $ h ^ { 2, 1 } $ is less successful as we manage to reach only 50 % accuracy for both datasets, but this is still better than the 16 % obtained with a simple neural network ( svm with gaussian kernel and feature engineering and sequential convolutional network reach at best 36 % ). this serves as a proof of concept that neural networks can be valuable to study the properties of geometries appearing in string theory.
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arxiv:2007.15706
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we investigate experimentally the receding of a contact line when a peltier module is pulled out of a water bath at constant speed, while a ice layer is also growing at constant speed on the peltier module. a steady regime is therefore reached for all the parameters used in this studied, corresponding to a dynamical stationnary meniscus. we show that the height of the meniscus provides most of the properties of the flow. for high pulling rate, it is related to the amount of liquid of the equivalent landau - levich ( ll ) film that would be extracted from the bath, which is eventually freezing as the plate is lifted upward. for smaller velocity, so that no ll film would be formed without freezing, the meniscus height is directly linked to the contact angle of water on ice in these conditions. solving numerically the meniscus equation taking into account the solidifcation of water, our results suggest that the contact angle of water on ice should be around $ 6 ^ \ circ $.
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arxiv:2409.00385
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activity classification has observed great success recently. the performance on small dataset is almost saturated and people are moving towards larger datasets. what leads to the performance gain on the model and what the model has learnt? in this paper we propose identity preserve transform ( ipt ) to study this problem. ipt manipulates the nuisance factors ( background, viewpoint, etc. ) of the data while keeping those factors related to the task ( human motion ) unchanged. to our surprise, we found popular models are using highly correlated information ( background, object ) to achieve high classification accuracy, rather than using the essential information ( human motion ). this can explain why an activity classification model usually fails to generalize to datasets it is not trained on. we implement ipt in two forms, i. e. image - space transform and 3d transform, using synthetic images. the tool will be made open - source to help study model and dataset design.
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arxiv:1912.06314
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crystallization of thin film materials by exploiting laser induced crystallization has been advancing for the past four decades. this unique thin film technique has been predominantly used in processing thin film materials made of a single chemical element ; however, harnessing this technique to extend its use for thin film materials containing multiple chemical elements ( e. g., metal oxides ) unlocks applications currently not accessible. in this study, laser crystallization of a cu2o strip was demonstrated. a continuous - wave laser diode with a micrometer - scale chevron - shaped beam profile ( micro chevron laser beam ) was used to crystallize cuo thin films covered with an amorphous carbon ( a - c ) cap layer, deposited on fused silica substrates. electron backscatter diffraction, raman spectroscopy, photoluminescence spectroscopy, and uv - vis spectroscopy were used to investigate the crystallinity and optical properties of the cu2o thin films revealing their unique characteristics associated with the crystallization process.
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arxiv:1911.09778
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we investigate the effective potential of the polyakov loop, which is the order parameter for the deconfinement phase transition in finite temperature qcd. our work is based on the hamiltonian approach in coulomb gauge where finite temperature $ t $ is introduced by compactifying one space direction. we briefly review this approach and extend earlier work in the yang - mills sector by including dynamical quarks. in a first approximation, we follow the usual functional approach and include only one - loop contributions to the energy, with the finite temperature propagators replaced by their $ t = 0 $ counter parts. it is found that this gives a poor description of the phase transition, in particular for the case of full qcd with $ n _ f = 3 $ light flavours. the physical reasons for this unexpected result are discussed, and pinned down to a relative weakness of gluon confinement compared to the deconfining tendency of the quarks. we attempt to overcome this issue by including the relevant gluon contributions from the two - loop terms to the energy. we find that the two - loop corrections have indeed a tendency to strengthen the gluon confinement and weaken the unphysical effects in the confining phase, while slightly increasing the ( pseudo - ) critical temperature $ t ^ \ ast $ at the same time. to fully suppress artifacts in the confining phase, we must tune the parameters to rather large values, increasing the critical temperature to $ t ^ \ ast \ approx 340 \, \ mathrm { mev } $ for $ g = su ( 2 ) $.
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arxiv:2209.04967
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borexino was the first experiment to detect solar neutrinos in real - time in the sub - mev region. in order to achieve high precision in the determination of neutrino rates, the detector design includes an internal and an external calibration system. this paper describes both calibration systems and the calibration campaigns that were carried out in the period between 2008 and 2011. we discuss some of the results and show that the calibration procedures preserved the radiopurity of the scintillator. the calibrations provided a detailed understanding of the detector response and led to a significant reduction of the systematic uncertainties in the borexino measurements.
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arxiv:1207.4816
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learning a shared dialog structure from a set of task - oriented dialogs is an important challenge in computational linguistics. the learned dialog structure can shed light on how to analyze human dialogs, and more importantly contribute to the design and evaluation of dialog systems. we propose to extract dialog structures using a modified vrnn model with discrete latent vectors. different from existing hmm - based models, our model is based on variational - autoencoder ( vae ). such model is able to capture more dynamics in dialogs beyond the surface forms of the language. we find that qualitatively, our method extracts meaningful dialog structure, and quantitatively, outperforms previous models on the ability to predict unseen data. we further evaluate the model ' s effectiveness in a downstream task, the dialog system building task. experiments show that, by integrating the learned dialog structure into the reward function design, the model converges faster and to a better outcome in a reinforcement learning setting.
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arxiv:1904.03736
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uncertainty relations provide fundamental limits on what can be said about the properties of quantum systems. for a quantum particle, the commutation relation of position and momentum observables entails heisenberg ' s uncertainty relation. a third observable is presented which satisfies canonical commutation relations with both position and momentum. the resulting triple of pairwise canonical observables gives rise to a heisenberg - type uncertainty relation for the product of three standard deviations. we derive the smallest possible value of this bound and determine the specific squeezed state which saturates the triple uncertainty relation. quantum optical experiments are proposed to verify our findings.
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arxiv:1407.0083
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we study the asymptotic hitting time $ \ tau ^ { ( n ) } $ of a family of markov processes $ x ^ { ( n ) } $ to a target set $ g ^ { ( n ) } $ when the process starts from a trap defined by very general properties. we give an explicit description of the law of $ x ^ { ( n ) } $ conditioned to stay within the trap, and from this we deduce the exponential distribution of $ \ tau ^ { ( n ) } $. our approach is very broad - - - it does not require reversibility, the target $ g $ does not need to be a rare event, and the traps and the limit on $ n $ can be of very general nature - - - and leads to explicit bounds on the deviations of $ \ tau ^ { ( n ) } $ from exponentially. we provide two non trivial examples to which our techniques directly apply.
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arxiv:1410.4814
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the atomization energies of molecules from first - principles density functional approximations improve from the local spin - density approximation ( lsda ) to the perdew - burke - ernzerhof ( pbe ) ) generalized gradient approximation ( gga ) to the strongly constrained and appropriately normed ( scan ) meta - gga, and their sensitivities to non - spherical components of the density increase in the same order. thus, these functional advances increase density sensitivity and imitate the exact constrained search over correlated wavefunctions better than that over ensembles. the diatomic molecules studied here, singlet c2 and f2 plus triplet b2 and o2, have cylindrically symmetric densities. because the densities of the corresponding atoms are non - spherical, the approximate kohn - sham potentials for the atoms have a lower symmetry than that of the external ( nuclear ) potential, so that the non - interacting wavefunctions are not eigenstates of the square of total orbital angular momentum, breaking a symmetry that yields a feature of the exact ground - state density. that spatial symmetry can be preserved by a non - self - consistent approach in which a self - consistent equilibrium - ensemble calculation is followed by integer re - occupation of the kohn - sham orbitals, as the first of several steps. the symmetry - preserving approach is different from symmetry restoration based upon projection. first - step space - ( and space - spin - ) symmetry preservation in atoms is shown to have a small effect on the atomization energies of molecules, quantifying earlier observations by fertig and kohn. thus, the standard kohn - sham way of calculating atomization energies, with self - consistent symmetry breaking to minimize the energy, is justified, at least for the common cases where the molecules cannot break symmetry.
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arxiv:2109.14113
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in this paper we prove uniqueness results for renormalized solutions to a class of nonlinear parabolic problems.
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arxiv:1111.5824
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we calculate the single particle spectral density of a normal ( non - superfluid ) two component gas of fermions in the bcs - bec crossover within a t - matrix approximation. we review how non - condensed pairs lead to a spectral density reminiscent of the ordered state, and explore how a gap - like feature in the spectrum evolves as one changes the polarization of the gas. as the gas is polarized we find that this pseudogap becomes more diffuse and moves away from the fermi level, reflecting the fact that fewer pairs are present but that they still play an important role in the excitations.
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arxiv:1012.0820
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we generalize quasi - linear means by restricting to the tail of the risk distribution and show that this can be a useful quantity in risk management since it comprises in its general form the value at risk, the tail value at risk and the entropic risk measure in a unified way. we then investigate the fundamental properties of the proposed measure and show its unique features and implications in the risk measurement process. furthermore, we derive formulas for truncated elliptical models of losses and provide formulas for selected members of such models.
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arxiv:1902.06941
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prior work on multilingual question answering has mostly focused on using large multilingual pre - trained language models ( lm ) to perform zero - shot language - wise learning : train a qa model on english and test on other languages. in this work, we explore strategies that improve cross - lingual transfer by bringing the multilingual embeddings closer in the semantic space. our first strategy augments the original english training data with machine translation - generated data. this results in a corpus of multilingual silver - labeled qa pairs that is 14 times larger than the original training set. in addition, we propose two novel strategies, language adversarial training and language arbitration framework, which significantly improve the ( zero - resource ) cross - lingual transfer performance and result in lm embeddings that are less language - variant. empirically, we show that the proposed models outperform the previous zero - shot baseline on the recently introduced multilingual mlqa and tydiqa datasets.
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arxiv:2012.05958
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aims : 3c345 was recently identified as a gamma - ray emitter, based on the first 20 months of fermi - lat data and optical monitoring. in this paper, a connection between the gamma - ray and optical variability of 3c345 and properties of its parsec - scale radio emission is investigated. methods : the fermi - lat data of 3c345, covering an energy range of 0. 1 - 300 gev, were combined with 32 very long baseline array observations of the object made at 43. 2 ghz in the period of january 2008 - march 2010. results : the vlba data reveal morphology and kinematics of the flow on scales of up to ~ 5 milliarcseconds ( mas ; deprojected linear distances of 380 parsecs ). the brightness temperature, t _ b ( r ), measured along the jet first decreases with distance proportional to r ^ - ( 0. 95 + / - 0. 69 ) and later exhibits a break at ~ 0. 3 mas, with t _ b ( r ) proportional to r ^ - ( 4. 11 + / - 0. 85 ) at larger separations. variations of the gamma - ray, optical and parsec - scale radio emission show a similar long - term trend persistent during the entire vlba monitoring period. the gamma - ray and optical variations on shorter time scales are related to structural changes in the jet on scales of ~ 0. 3 mas ( ~ 23 parsecs, deprojected ), with the gamma - ray and optical flares possibly related to the evolution of four distinct superluminal components identified in the flow. conclusions : the observations indicate that both the quiescent and flaring components of the gamma - ray emission are produced in a region of the jet of ~ 23 pc in extent. this region may mark the compton - loss dominated zone of the flow and its large extent may favor the synchrotron self - compton mechanism for gamma - ray production in the relativistic jet of the quasar 3c345.
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arxiv:1111.2045
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we report on ab - initio ncsm calculations of the a = 4 mirror lambda hypernuclei lambda - 4h and lambda - 4he, using the bonn - juelich lo chiral eft yn potentials plus a csb lambda0 - - sigma0 mixing vertex. in addition to reproducing rather well the 0 + ( g. s. ) and 1 + ( exc. ) binding energies, these four - body calculations demonstrate for the first time that the observed csb splitting of mirror levels, reaching hundreds of kev for 0 + ( g. s. ), can be reproduced using realistic theoretical interaction models, although with a non - negligible momentum cutoff dependence. our results are discussed in relation to recent measurements of the lambda - 4h ( 0 + g. s. ) binding energy [ mami a1 collaboration, phys. rev. lett. 114, 232501 ( 2015 ) ] and the lambda - 4he ( 1 + exc. ) excitation energy [ j - parc e13 collaboration, phys. rev. lett. 115, 222501 ( 2015 ) ].
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arxiv:1512.01049
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since the early sixties and seventies it has been known that the regular and context - free languages are characterized by definability in the monadic second - order theory of certain structures. more recently, these descriptive characterizations have been used to obtain complexity results for constraint - and principle - based theories of syntax and to provide a uniform model - theoretic framework for exploring the relationship between theories expressed in disparate formal terms. these results have been limited, to an extent, by the lack of descriptive characterizations of language classes beyond the context - free. recently, we have shown that tree - adjoining languages ( in a mildly generalized form ) can be characterized by recognition by automata operating on three - dimensional tree manifolds, a three - dimensional analog of trees. in this paper, we exploit these automata - theoretic results to obtain a characterization of the tree - adjoining languages by definability in the monadic second - order theory of these three - dimensional tree manifolds. this not only opens the way to extending the tools of model - theoretic syntax to the level of tals, but provides a highly flexible mechanism for defining tags in terms of logical constraints. this is the full version of a paper to appear in the proceedings of coling - acl ' 98 as a project note.
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arxiv:cmp-lg/9805008
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in this paper we study the classical scheduling problem of minimizing the total weighted completion time on a single machine with the constraint that one specific job must be scheduled at a specified position. we give dynamic programs with pseudo - polynomial running time, and a fully polynomial - time approximation scheme ( fptas ).
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arxiv:1710.10904
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we show a microscopic derivation of a quantum master equation with counting terms which describes the electron statistics. a localized spin behaves as a probe whose precession angle monitors the net electron current by the magnetic - moment interaction. the probe hamiltonian is proportional to the current, and is determined self - consistently for a model of a quantum dot. then it turns out that the quantum master equation for the spin - precession contains the counting terms. as an application, we show the fluctuation theorem for the electron current.
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arxiv:1009.1428
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we report on the first production of an antihydrogen beam by charge exchange of 6. 1 kev antiprotons with a cloud of positronium in the gbar experiment at cern. the antiproton beam was delivered by the ad / elena facility. the positronium target was produced from a positron beam itself obtained from an electron linear accelerator. we observe an excess over background indicating antihydrogen production with a significance of 3 - 4 standard deviations.
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arxiv:2306.15801
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we propose a process algebra for wireless mesh networks that combines novel treatments of local broadcast, conditional unicast and data structures. in this framework, we model the ad - hoc on - demand distance vector ( aodv ) routing protocol and ( dis ) prove crucial properties such as loop freedom and packet delivery.
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arxiv:1512.07319
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this paper presents a framework to jointly optimize the design and control of an electric race car equipped with a multiple - gear transmission, specifically accounting for the discrete gearshift dynamics. we formulate the problem as a mixed - integer optimal control problem, and deal with its complexity by combining convex optimization and pontryagin ' s minimum principle in a computationally efficient iterative algorithm satisfying necessary conditions for optimality upon convergence. finally, we leverage our framework to compute the achievable lap time of a race car equipped with a fixed - gear transmission, a continuously variable transmission and a multiple - gear transmission with 2 to 4 speeds, revealing that a multiple - gear transmission can strike the best trade - off in terms of electric motor control, and transmission weight and efficiency, ultimately yielding the overall best lap time.
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arxiv:2311.03545
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the search for exoplanets has revealed a diversity of planetary system architectures, the vast majority of which diverge significantly from the template of the solar system. in particular, giant planets beyond the snow line are relatively rare, especially for low - mass stars, placing the solar system within a small category of systems with multiple giant planets at large separations. an exoplanetary system of note is that of hd 141399, consisting of a k dwarf host star that harbors four giant planets with separations extending to $ \ sim $ 4. 5 au. the architecture of the system creates a complex pattern of mean motion resonances and gravitationally perturbed regions that may exclude the presence of other planets, including within the habitable zone of the system. here, we present the results of dynamical simulations that explore the interaction of the known planets of the system, their apsidal trajectories, resonance locations, and dynamical evolution. we further investigate the results of injecting earth - mass planets and provide the regions of dynamical viability within the habitable zone where terrestrial planets may maintain long - term stability. we discuss these results in the context of the importance of giant planets for volatile delivery and planetary habitability considerations.
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arxiv:2310.00860
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we present an example of a disconnected lie group for which there is no universal covering ( as lie group ).
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arxiv:math/0401213
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background : the n - back and paced auditory serial addition test ( pasat ) are commonly used verbal working memory tasks that have partially overlapping uses in clinical and experimental psychology. we performed three activation likelihood estimation ( ale ) meta - analyses, comparing two load levels of the n - back task ( 2 - back, 3 - back ) to the pasat and to each - other. these analyses aimed to determine the involvement of cognitive and emotional brain regions for these tasks. results : we observed higher overall likelihood of activation the frontal eye fields in the 3 - back. the pasat exhibited higher overall activation in the bilateral supplementary motor areas ( sma ), left supramarginal gyrus, and left superior parietal lobule. furthermore, the 3 - back exhibited higher activation in the right sma, and anterior mid - cingulate cortex versus the 2 - back, and the pasat exhibited higher activation in a cluster near the right premotor area versus the 2 - back. a laterality effect was observed in the dorsolateral prefrontal cortex between the pasat ( left ) and 3 - back ( right ). these data suggest greater activation of regions traditionally associated with the phonological loop during the pasat, compared to the 2 - and 3 - back tasks. furthermore, individual ale analyses suggest involvement of emotional processing and salience network regions ( insula, cingulate ) in addition to the well - established verbal working memory regions ( broca ' s region, bilateral sma, premotor, posterior parietal cortices ) in all 3 tasks. conclusions : here we identify regions activated by the pasat, which has not been meta - analytically reviewed prior to this study. using ale meta - analysis, we have also identified meaningful differences in activation associated with specific cognitive and emotional aspects of verbal working memory during these tasks.
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arxiv:1807.02755
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we study ( p, q ) = ( 2, 4k ) minimal superstrings within the minimal superstring field theory constructed in hep - th / 0611045. we explicitly give a solution to the w _ { 1 + \ infty } constraints by using charged d - instanton operators, and show that the ( m, n ) - instanton sector with m positive - charged and n negative - charged zz - branes is described by an ( m + n ) \ times ( m + n ) supermatrix model. we argue that the supermatrix model can be regarded as an open string field theory on the multi zz - brane system.
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arxiv:hep-th/0701031
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for the task of moving a set of indistinguishable agents on a connected graph with unit edge distance to an arbitrary set of goal vertices, free of collisions, we propose a fast distance optimal control algorithm that guides the agents into the desired formation. moreover, we show that the algorithm also provides a tight convergence time guarantee ( time optimality and distance optimality cannot be simultaneously satisfied ). our generic graph formulation allows the algorithm to be applied to scenarios such as grids with holes ( modeling obstacles ) in arbitrary dimensions. simulations, available online, confirm our theoretical developments.
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arxiv:1204.3820
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the syntactic calculus of lambek is a deductive system for the multiplicative fragment of intuitionistic non - commutative linear logic. as a fine - grained calculus of resources, it has many applications, mostly in formal computational investigations of natural languages. this paper introduces a calculus of beta - eta - long normal forms for derivations in the lambek calculus with multiplicative unit and conjunction among its logical connectives. reduction to normal form follows the normalization by evaluation ( nbe ) strategy : ( i ) evaluate a derivation in a kripke model of lambek calculus ; ( ii ) extract normal forms from the obtained semantic values. the implementation of the nbe algorithm requires the presence of a strong monad in the kripke interpretation of positive formulae, in analogy with the extension of intuitionistic propositional logic with falsity and disjunction. the nbe algorithm can also be instantiated with minor variations to calculi for related substructural logics, such as multiplicative and dual intuitionistic linear logic ( mill and dill ).
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arxiv:2204.06719
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in this paper, we propose a method for generating visually protected images, referred to as gradient - preserving images. the protected images allow us to directly extract histogram - of - oriented - gradients ( hog ) features for privacy - preserving machine learning. in an experiment, hog features extracted from gradient - preserving images are applied to a face recognition algorithm to demonstrate the effectiveness of the proposed method.
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arxiv:2104.01350
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we give alternative computations of the schur multiplier of $ sp ( 2g, \ mathbb z / d \ mathbb z ) $, when $ d $ is divisible by 4 and $ g \ geq 4 $ : a first one using $ k $ - theory arguments based on the work of barge and lannes and a second one based on the weil representations of symplectic groups arising in abelian chern - simons theory. we can also retrieve this way deligne ' s non - residual finiteness of the universal central extension $ \ widetilde { sp ( 2g, \ mathbb z ) } $. we prove then that the image of the second homology into finite quotients of symplectic groups over a dedekind domain of arithmetic type are torsion groups of uniformly bounded size. in contrast, quantum representations produce for every prime $ p $, finite quotients of the mapping class group of genus $ g \ geq 3 $ whose second homology image has $ p $ - torsion. we further derive that all central extensions of the mapping class group are residually finite and deduce that mapping class groups have serre ' s property $ a _ 2 $ for trivial modules, contrary to symplectic groups. eventually we compute the module of coinvariants $ h _ 2 ( \ mathfrak { sp } _ { 2g } ( 2 ) ) _ { sp ( 2g, \ mathbb z / 2 ^ k \ mathbb z ) } = \ mathbb z / 2 \ mathbb z $.
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arxiv:2004.04129
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the koebe circle packing theorem states that every finite planar graph can be realized as the nerve of a packing of ( non - congruent ) circles in r ^ 3. we investigate the average kissing number of finite packings of non - congruent spheres in r ^ 3 as a first restriction on the possible nerves of such packings. we show that the supremum k of the average kissing number for all packings satisfies 12. 566 ~ 666 / 53 < = k < 8 + 4 * sqrt ( 3 ) ~ 14. 928 we obtain the upper bound by a resource exhaustion argument and the upper bound by a construction involving packings of spherical caps in s ^ 3. our result contradicts two naive conjectures about the average kissing number : that it is unbounded, or that it is supremized by an infinite packing of congruent spheres.
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arxiv:math/9405218
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let $ s $ be a source point and $ t $ be a destination point inside an $ n $ - vertex simple polygon $ p $. euclidean shortest paths and minimum - link paths between $ s $ and $ t $ inside $ p $ have been well studied. both these kinds of paths are simple and piecewise - convex. however, computing optimal paths in the context of diffuse or specular reflections does not seem to be an easy task. a path from a light source $ s $ to $ t $ inside $ p $ is called a diffuse reflection path if the turning points of the path lie in the interiors of the boundary edges of $ p $. a diffuse reflection path is said to be optimal if it has the minimum number of turning points amongst all diffuse reflection paths between $ s $ and $ t $. the minimum diffuse reflection path may not be simple. the problem of computing the minimum diffuse reflection path in low degree polynomial time has remained open. in our quest for understanding the geometric structure of the minimum diffuse reflection paths vis - a - vis shortest paths and minimum link paths, we define a new kind of diffuse reflection path called a constrained diffuse reflection path where ( i ) the path is simple, ( ii ) it intersects only the eaves of the euclidean shortest path between $ s $ and $ t $, and ( iii ) it intersects each eave exactly once. for computing a minimum constrained diffuse reflection path from $ s $ to $ t $, we present an $ o ( n ( n + \ beta ) ) $ time algorithm, where $ \ beta = \ theta ( n ^ 2 ) $ in the worst case. here, $ \ beta $ depends on the shape of the polygon. we also establish some properties relating minimum constrained diffuse reflection paths and minimum diffuse reflection paths. constrained diffuse reflection paths introduced in this paper provide new geometric insights into the hitherto unknown structures and shapes of optimal reflection paths.
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arxiv:1304.4320
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we report discovery of the lowest mass ratio exoplanet to be found by the microlensing method in the light curve of the event ogle ~ 2016 - - blg - - 1195. this planet revealed itself as a small deviation from a microlensing single lens profile from an examination of the survey data soon after the planetary signal. the duration of the planetary signal is $ \ sim 2. 5 \, $ hours. the measured ratio of the planet mass to its host star is $ q = 4. 2 \ pm 0. 7 \ times10 ^ { - 5 } $. we further estimate that the lens system is likely to comprise a cold $ \ sim $ 3 earth mass planet in a $ \ sim \, $ 2 au wide orbit around a 0. 2 solar mass star at an overall distance of 7. 1 kpc.
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arxiv:1703.08639
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topological systems, such as fractional quantum hall liquids, promise to successfully combat environmental decoherence while performing quantum computation. these highly correlated systems can support non - abelian anyonic quasiparticles that can encode exotic entangled states. to reveal the non - local character of these encoded states we demonstrate the violation of suitable bell inequalities. we provide an explicit recipe for the preparation, manipulation and measurement of the desired correlations for a large class of topological models. this proposal gives an operational measure of non - locality for anyonic states and it opens up the possibility to violate the bell inequalities in quantum hall liquids or spin lattices.
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arxiv:0810.4319
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in this paper, we characterize the weighted local hardy spaces $ h ^ p _ \ rho ( \ omega ) $ related to the critical radius function $ \ rho $ and weights $ \ omega \ in a _ { 1 } ^ { \ rho, \, \ infty } ( \ mathbb { r } ^ { n } ) $ by localized riesz transforms $ \ widehat { r } _ j $, in addition, we give a characterization of weighted hardy spaces $ h ^ { 1 } _ { \ cal l } ( \ omega ) $ via riesz tranforms associated to schr \ " { o } dinger operator $ \ cal l $, where $ \ l = - \ delta + v $ is a schr \ " { o } dinger operator on $ \ mathbb { r } ^ { n } $ ( $ n \ ge 3 $ ) and $ v $ is a nonnegative function satisfying the reverse h \ " older inequality.
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arxiv:1405.5277
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we apply the hybrid monte carlo ( hmc ) algorithm to the financial time sires analysis of the stochastic volatility ( sv ) model for the first time. the hmc algorithm is used for the markov chain monte carlo ( mcmc ) update of volatility variables of the sv model in the bayesian inference. we compute parameters of the sv model from the artificial financial data and compare the results from the hmc algorithm with those from the metropolis algorithm. we find that the hmc decorrelates the volatility variables faster than the metropolis algorithm. we also make an empirical analysis based on the yen / dollar exchange rates.
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arxiv:0807.4394
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in this paper, we present a three - point without memory iterative method based on kung and traub ' s method for solving non - linear equations in one variable. the proposed method has eighth - order convergence and costs only four function evaluations each iteration which supports the kung - traub conjecture on the optimal order of convergence. consequently, this method possesses very high computational efficiency. we present the construction, the convergence analysis, and the numerical implementation of the method. furthermore, comparisons with some other existing optimal eighth - order methods concerning accuracy and basins of attraction for several test problems will be given.
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arxiv:1508.01748
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in this letter, we consider a dual - hop cooperative network assisted by multiple reconfigurable intelligent surfaces ( riss ). assuming that the ris with the highest instantaneous end - to - end signal - to - noise ratio ( snr ) is selected to aid the communication, the outage probability ( op ) and average sum - rate are investigated. specifically, an exact analysis for the op is developed. in addition, relying on the extreme value theory, closed - form expressions for the asymptotic op and asymptotic sum - rate are derived, based on which the capacity scaling law is established. our results are corroborated through simulations and insightful discussions are provided. in particular, our analysis shows that the number of riss as well as the number of reflecting elements play a crucial role in the capacity scaling law of multiple ris - aided cooperative networks. also, comparisons with relay - aided systems are carried out to demonstrate that the proposed system setup outperforms relaying schemes both in terms of the op and average sum - rate.
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arxiv:2007.13293
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topological magnetic structures are promising candidates for resilient information storage. an elementary example are spin helices in one - dimensional easy - plane quantum magnets. to quantify their stability, we numerically implement the stochastic schr \ " odinger equation and time - dependent perturbation theory for spin chains with fluctuating local magnetic fields. we find two classes of quantum spin helices that can reach and even exceed ground - state stability : spin - current - maximizing helices and, for fine - tuned boundary conditions, the recently discovered " phantom helices ". beyond that, we show that the helicity itself ( left - or right - rotating ) is even more stable. we explain these findings by separated helical sectors and connect them to topological sectors in continuous spin systems. the resulting helical protection mechanism is a promising phenomenon towards stabilizing helical quantum structures, e. g., in ultracold atoms and solid state systems. we also identify an - up to our knowledge - previously unknown new type of phantom helices.
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arxiv:2302.02603
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we introduce a general definition of hybrid transforms for constructible functions. these are integral transforms combining lebesgue integration and euler calculus. lebesgue integration gives access to well - studied kernels and to regularity results, while euler calculus conveys topological information and allows for compatibility with operations on constructible functions. we conduct a systematic study of such transforms and introduce two new ones : the euler - fourier and euler - laplace transforms. we show that the first has a left inverse and that the second provides a satisfactory generalization of govc and hepworth ' s persistent magnitude to constructible sheaves, in particular to multi - parameter persistent modules. finally, we prove index - theoretic formulae expressing a wide class of hybrid transforms as generalized euler integral transforms. this yields expectation formulae for transforms of constructible functions associated to ( sub ) level - sets persistence of random gaussian filtrations.
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arxiv:2111.07829
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many practical sampling patterns for function approximation on the rotation group utilizes regular samples on the parameter axes. in this paper, we relate the mutual coherence analysis for sensing matrices that correspond to a class of regular patterns to angular momentum analysis in quantum mechanics and provide simple lower bounds for it. the products of wigner d - functions, which appear in coherence analysis, arise in angular momentum analysis in quantum mechanics. we first represent the product as a linear combination of a single wigner d - function and angular momentum coefficients, otherwise known as the wigner 3j symbols. using combinatorial identities, we show that under certain conditions on the bandwidth and number of samples, the inner product of the columns of the sensing matrix at zero orders, which is equal to the inner product of two legendre polynomials, dominates the mutual coherence term and fixes a lower bound for it. in other words, for a class of regular sampling patterns, we provide a lower bound for the inner product of the columns of the sensing matrix that can be analytically computed. we verify numerically our theoretical results and show that the lower bound for the mutual coherence is larger than welch bound. besides, we provide algorithms that can achieve the lower bound for spherical harmonics.
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arxiv:2010.02344
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for the first time the scientific community in latin america working at the forefront of research in high energy, cosmology and astroparticle physics ( hecap ) have come together to discuss and provide scientific input towards the development of a regional strategy. the present document, the latin american hecap physics briefing book, is the result of this ambitious bottom - up effort. this report contains the work performed by the preparatory group to synthesize the main contributions and discussions for each of the topical working groups. this briefing book discusses the relevant emerging projects developing in the region and considers potentially impactful future initiatives and participation of the latin american hecap community in international flagship projects to provide the essential input for the creation of a long - term hecap strategy in the region.
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arxiv:2104.06852
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we discuss phenomenological consequences of some class of supersymmetric seesaw models in which the right - handed ( s ) neutrino mass is given to be tev scale. in this scenario, scalar trilinear interaction of higgs - slepton - ( right - handed ) sneutrino is enhanced. we show that the 1 - loop correction by sneutrino exchange to the lightest higgs boson mass destructively interferes with top - stop contributions in the minimal susy standard model. we find that a decay of charged higgs boson into sneutrino and charged slepton is sizably enhanced and hence it gives rise to a distinctive signal at future collider experiments in some parameter space.
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arxiv:0710.2214
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the aim of this paper is to discuss a relationship between total positivity and planar directed networks. we show that the inverse boundary problem for these networks is naturally linked with the study of the totally nonnegative grassmannian. we investigate its cell decomposition, where the cells are the totally nonnegative parts of the matroid strata. the boundary measurements of networks give parametrizations of the cells. we present several different combinatorial descriptions of the cells, study the partial order on the cells, and describe how they are glued to each other.
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arxiv:math/0609764
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we show that any direction in the plane occurs as the unique non - expansive direction of a \ mathbb { z } ^ { 2 } action, answering a question of boyle and lind. in the case of rational directions, the subaction obtained is non - trivial. we also establish that a cellular automaton can have zero lyapunov exponents and at the same time act sensitively ; and more generally, for any positive real \ theta there is a cellular automaton acting on an appropriate subshift with \ lambda ^ { + } = - \ lambda ^ { - } = \ theta.
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arxiv:0906.0609
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econophysics provides a strategy for understanding the potential mechanisms underlying the anomalous distribution of wealth found in real societies. we present a computational nonlinear stochastic model for the distribution of wealth that depends upon three parameters and two mechanisms : trade and investment. to avoid economic paradoxes, the trade mechanism is assumed to be related to the poorer trader ' s wealth and to statistically advantage the poorer of the two traders. the two mechanisms together are shown to generate a distribution that reproduces the full range of the empirical wealth distribution, and not only the inverse power - law tail that pareto found in western societies at the end of the 19th century.
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arxiv:cond-mat/0306579
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we present a new algorithm for predicting the near - term trajectories of road - agents in dense traffic videos. our approach is designed for heterogeneous traffic, where the road - agents may correspond to buses, cars, scooters, bicycles, or pedestrians. we model the interactions between different road - agents using a novel lstm - cnn hybrid network for trajectory prediction. in particular, we take into account heterogeneous interactions that implicitly accounts for the varying shapes, dynamics, and behaviors of different road agents. in addition, we model horizon - based interactions which are used to implicitly model the driving behavior of each road - agent. we evaluate the performance of our prediction algorithm, traphic, on the standard datasets and also introduce a new dense, heterogeneous traffic dataset corresponding to urban asian videos and agent trajectories. we outperform state - of - the - art methods on dense traffic datasets by 30 %.
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arxiv:1812.04767
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in this paper, we propose a generative adversarial network ( gan ) approach for efficiently computing volatility surfaces. the idea is to make use of the special gan neural architecture so that on one hand, we can learn volatility surfaces from training data and on the other hand, enforce no - arbitrage conditions. in particular, the generator network is assisted in training by a discriminator that evaluates whether the generated volatility matches the target distribution. meanwhile, our framework trains the gan network to satisfy the no - arbitrage constraints by introducing penalties as regularization terms. the proposed gan model allows the use of shallow networks which results in much less computational costs. in our experiments, we demonstrate the performance of the proposed method by comparing with the state - of - the - art methods for computing implied and local volatility surfaces. we show that our gan model can outperform artificial neural network ( ann ) approaches in terms of accuracy and computational time.
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arxiv:2304.13128
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generalization of the self - similar solution for ultrarelativistic shock waves ( blandford & mckee, 1976 ) is obtained in presence of losses localized on the shock front or distributed in the downstream medium. it is shown that there are two qualitatively different regimes of shock deceleration, corresponding to small and large losses. we present the temperature, pressure and density distributions in the downstream fluid as well as lorentz factor as a function of distance from the shock front.
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arxiv:astro-ph/0501192
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let k be a number field. for any system of semisimple mod l galois representations { \ phi _ l : gal _ k - > gl _ n ( f _ l ) } arising from \ ' etale cohomology, there exists a finite normal extension l of k such that if we denote \ phi _ l ( gal _ k ) and \ phi _ l ( gal _ l ) by respectively \ gamma _ l and \ gamma _ l for all l, and let s _ l be the f _ l - semisimple subgroup of gl _ n associated to \ gamma _ l ( or \ gamma _ l ) by nori [ no87 ] for all sufficiently large l, then the following statements hold for all sufficiently large l : a ( i ) the formal character of s _ l - > gl _ n is independent of l and is equal to the formal character of the tautological representation of the derived group of the identity component of the monodromy group of the corresponding semi - simplified l - adic galois representation. a ( ii ) the non - cyclic composition factors of \ gamma _ l and s _ l ( f _ l ) are identical. therefore, the composition factors of \ gamma _ l are finite simple groups of lie type of characteristic l and cyclic groups. b ( i ) the total l - rank rk _ l \ gamma _ l of \ gamma _ l is equal to the rank of s _ l and is therefore independent of l. b ( ii ) the a _ n - type l - rank rk _ l ^ { a _ n } \ gamma _ l of \ gamma _ l for n belonging to n \ { 1, 2, 3, 4, 5, 7, 8 } and the parity of ( rk _ l ^ { a _ 4 } \ gamma _ l ) / 4 are independent of l.
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arxiv:1305.2001
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in this paper we consider the liouville equation $ \ delta u + \ lambda ^ 2 e ^ { \, u } = 0 $ with dirichlet boundary conditions in a two dimensional, doubly connected domain $ \ omega $. we show that there exists a simple, closed curve $ \ gamma \ subset \ omega $ such that for a sequence $ \ lambda _ n \ to 0 $ and a sequence of solutions $ u _ { n } $ it holds $ \ frac { u _ { n } } { \ log \ frac { 1 } { \ lambda _ n } } \ to h $, where $ h $ is a harmonic function in $ \ omega \ setminus \ gamma $ and $ \ frac { \ lambda _ n ^ 2 } { \ log \ frac { 1 } { \ lambda _ n } } \ int _ \ omega e ^ { \, u _ n } \, dx \ to 8 \ pi c _ \ omega $, where $ c _ \ omega $ is a constant depending on the conformal class of $ \ omega $ only.
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arxiv:1808.00127
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in - beam $ \ gamma $ - ray spectroscopy was used to study excited states of the neutron - deficient nucleus $ ^ { 37 } $ k populated in fast - beam inelastic - scattering and proton - removal reactions at high - momentum loss. new $ \ gamma $ - ray transitions and $ \ gamma \ gamma $ coincidence relationships were established using the $ \ gamma $ - ray tracking array gretina. the extension of the level scheme up to the first $ ( 13 / 2 ^ - ) $ state highlights the potential of this recently demonstrated population pathway for studies of isospin symmetry involving mirror - energy differences. the nature of the newly identified states is discussed in comparison to shell - model calculations with the fsu cross - shell effective interaction. the calculated occupation numbers of individual orbitals are shown to offer a consistent explanation of the measured mirror - energy differences between $ ^ { 37 } $ k and $ ^ { 37 } $ ar.
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arxiv:2411.15563
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we study vector boson pair production at $ lhc $ and $ ssc $, taking into account the effects generated by the anomalous vector boson and higgs couplings induced by the operators $ { \ cal o } _ w $ and $ { \ cal o } _ { uw } $, which are the only dim = 6 operators preserving $ su ( 2 ) _ c $. these operators lead to enhanced production of transverse vector bosons, as opposed to the enhanced production of longitudinal gauge bosons, induced in case $ m _ h \ gsim 1 \ tev $, by dim = 4 terms already existing in the standard model lagrangian. for vector boson pair masses larger than $ 1 \ tev $, we establish very simple approximate expressions for the standard as well as the non - standard helicity amplitudes for $ q \ bar q $ annihilation and vector boson fusion, which accurately describe the physics. these expressions should simplify the experimental search for such interactions. we finally discuss the observability and the disentangling of these interactions.
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arxiv:hep-ph/9309324
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we give a representation, in terms of iterated mellin - barnes integrals, of periods on multi - moduli calabi - yau manifolds arising in superstring theory. using this representation and the theory of multidimensional residues, we present a method for analytic continuation of the fundamental period in the form of horn series.
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arxiv:hep-th/9609215
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