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cosmological models with variable and modified equations of state for dark energy are confronted with observational data, including type ia supernovae, hubble parameter data $ h ( z ) $ from different sources, and observational manifestations of cosmic microwave background radiation ( cmb ). we consider scenarios generalizing the $ \ lambda $ cdm, $ w $ cdm, and chevallier - - polarski - - linder ( cpl ) models with nonzero curvature and compare their predictions. the most successful model with the dark energy equation of state $ w = w _ 0 + w _ 1 ( 1 - a ^ 2 ) / 2 $ was studied in detail. these models are interesting in possibly alleviating the hubble constant $ h _ 0 $ tension, but they achieved a modest success in this direction with the considered observational data.
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arxiv:2203.14336
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we consider the actions of ( semi ) groups on a locally compact group by automorphisms. we show the equivalence of distality and pointwise distality for the actions of a certain class of groups. we also show that a compactly generated locally compact group of polynomial growth has a compact normal subgroup $ k $ such that $ g / k $ is distal and the conjugacy action of $ g $ on $ k $ is ergodic ; moreover, if $ g $ itself is ( pointwise ) distal then $ g $ is lie projective. we prove a decomposition theorem for contraction groups of an automorphism under certain conditions. we give a necessary and sufficient condition for distality of an automorphism in terms of its contraction group. we compare classes of ( pointwise ) distal groups and groups whose closed subgroups are unimodular. in particular, we study relations between distality, unimodularity and contraction subgroups.
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arxiv:1201.4287
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we introduce the notion of multipass automata as a generalization of pushdown automata and study the classes of languages accepted by such machines. the class of languages accepted by deterministic multipass automata is exactly the boolean closure of the class of deterministic context - free languages while the class of languages accepted by nondeterministic multipass automata is exactly the class of poly - context - free languages, that is, languages which are the intersection of finitely many context - free languages. we illustrate the use of these automata by studying groups whose word problems are in the above classes.
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arxiv:1404.7442
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designing superconducting electronic devices involves a careful study of all the elements in the circuit, including the superconducting bias leads, however, the effect of the bias current leads on the performance of the device have not been previously addressed. in this work, we introduce a theoretical model for two - dimensional superconducting quantum interference device ( squid ) arrays capable of simulating the response of devices with different bias current configurations. first, we compare uniformly biased and centre biased squid arrays by investigating the voltage versus magnetic flux response, maximum transfer function and voltage modulation depth. then, we calculate the time - averaged fluxoid distributions for 1d and 2d centre biased arrays. finally, we study the performance of the two bias current configurations depending on array size, screening parameter, thermal noise strength and kinetic self - inductance fraction. our calculations reveal : ( i ) centre biased 1d parallel squid arrays present an unusual voltage response caused by the asymmetric fluxoid distribution ; ( ii ) the optimal transfer function of centre biased arrays strongly depends on the number of junctions in parallel ; ( iii ) the performance of centre biased arrays approaches the uniform biased ones when the number of junctions in series exceeds those in parallel ; ( iv ) while the screening parameter and the thermal noise strength clearly affect the device performance, the kinetic self - inductance fraction seems to play only a secondary role.
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arxiv:2303.05609
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we derive the power spectrum of primordial quantum fluctuations in an inflationary universe for curvature parameter $ { \ mathcal k } = 1 $. this is achieved through a born - - oppenheimer type of approximation scheme from the wheeler - - dewitt equation of canonical quantum gravity using gauge - invariant variables. compared to the flat model, the closed model exhibits a deficit of power at large scales.
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arxiv:2111.07835
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pre - training and fine - tuning is a paradigm for alleviating the data scarcity problem in end - to - end speech translation ( e2e st ). the commonplace " modality gap " between speech and text data often leads to inconsistent inputs between pre - training and fine - tuning. however, we observe that this gap occurs in the early stages of fine - tuning, but does not have a major impact on the final performance. on the other hand, we find that there has another gap, which we call the " capacity gap " : high resource tasks ( such as asr and mt ) always require a large model to fit, when the model is reused for a low resource task ( e2e st ), it will get a sub - optimal performance due to the over - fitting. in a case study, we find that the regularization plays a more important role than the well - designed modality adaption method, which achieves 29. 0 for en - de and 40. 3 for en - fr on the must - c dataset. code and models are available at https : / / github. com / hannlp / tab.
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arxiv:2306.07650
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we provide a generalization of continued fractions to the heisenberg group. we prove an explicit estimate on the rate of convergence of the infinite continued fraction and several surprising analogs of classical formulas about continued fractions. we then discuss dynamical properties of the associated gauss map, comparing them with base - $ b $ expansions on the heisenberg group and continued fractions on the complex plane.
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arxiv:1302.6121
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plasma - molecular interactions generate molecular ions which react with the plasma and contribute to detachment through molecular activated recombination ( mar ), reducing the ion target flux, and molecular activated dissociation ( mad ), both of which create excited atoms. hydrogenic emission from these atoms have been detected experimentally in detached tcv, jet and mast - u deuterium plasmas. the tcv findings, however, were in disagreement with solps - iter simulations for deuterium indicating a molecular ion density ( $ d _ 2 ^ + $ ) that was insufficient to lead to significant hydrogenic emission, which was attributed to underestimates of the molecular charge exchange rate ( $ d _ 2 + d ^ + \ rightarrow d _ 2 ^ + + d $ ) for deuterium ( obtained by rescaling the hydrogen rates by their isotope mass ). in this work, we have performed new solps - iter simulations with the default rate setup and a modified rate setup where ion isotope mass rescaling was disabled. this increased the $ d _ 2 ^ + $ content by $ > \ times 100 $. by disabling ion isotope mass rescaling : 1 ) the total ion sinks are more than doubled due to the inclusion of mar ; 2 ) the additional mar causes the ion target flux to roll - over during detachment ; 3 ) the total $ d \ alpha $ emission in the divertor increases during deep detachment by roughly a factor four ; 4 ) the neutral atom density in the divertor is doubled due to mad, leading to a 50 \ % increase in neutral pressure ; 5 ) total hydrogenic power loss is increased by up to 60 \ % due to mad. these differences result in an improved agreement between the experiment and the simulations in terms of spectroscopic measurements, ion source / sink inferences and the occurrence of an ion target flux roll - over.
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arxiv:2301.11298
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we construct a family of map which is shown to be positive when imposing certain condition on the parameters. then we show that the constructed map can never be completely positive. after tuning the parameters, we found that the map still remain positive but it is not completely positive. we then use the positive but not completely positive map in the detection of bound entangled state and negative partial transpose entangled states.
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arxiv:2104.13308
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the extended - mhd nimrod code [ c. r. sovinec and j. r. king, j. comput. phys. 229, 5803 ( 2010 ) ] is verified against the ideal - mhd elite code [ h. r. wilson et al. phys. plasmas 9, 1277 ( 2002 ) ] on a diverted tokamak discharge. when the nimrod model complexity is increased incrementally, resistive and first - order finite - larmour radius effects are destabilizing and stabilizing, respectively. the full result is compared to local analytic calculations which are found to overpredict both the resistive destabilization and drift stabilization in comparison to the nimrod computations.
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arxiv:1702.00042
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during the embedded stage of star formation, bipolar molecular outflows and uv radiation from the protostar are important feedback processes. our aim is to quantify the feedback, mechanical and radiative, for a large sample of low - mass sources. the outflow activity is compared to radiative feedback in the form of uv heating by the accreting protostar to search for correlations and evolutionary trends. large - scale maps of 26 young stellar objects, which are part of the herschel wish key program are obtained using the champ + instrument on the apex ( 12co and 13co 6 - 5 ), and the harp - b instrument on the jcmt ( 12co and 13co 3 - 2 ). maps are used to determine outflow parameters and envelope models are used to quantify the amount of uv - heated gas and its temperature from 13co 6 - 5 observations. all sources in our sample show outflow activity and the outflow force, f _ co, is larger for class 0 sources than for class i sources, even if their luminosities are comparable. the outflowing gas typically extends to much greater distances than the power - law envelope and therefore influences the surrounding cloud material directly. comparison of the co 6 - 5 results with herschel - hifi h2o and pacs high - j co lines, both tracing currently shocked gas, shows that the two components are linked, even though the transitions do not probe the same gas. the link does not extend down to co 3 - 2. the conclusion is that co 6 - 5 depends on the shock characteristics ( density and velocity ), whereas co 3 - 2 is more sensitive to conditions in the surrounding environment ( density ). the radiative feedback is responsible for increasing the gas temperature by a factor of two, up to 30 - 50 k, on scales of a few thousand au, particularly along the direction of the outflow. the mass of the uv heated gas exceeds the mass contained in the entrained outflow in the inner ~ 3000 au and is therefore at least as important on small scales.
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arxiv:1501.03259
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the present work introduces new scalar and fermionic degrees of freedom to the standard model. while the scalar sector is augmented by a complex scalar triplet and a doubly charged scalar singlet, the fermionic sector is extended by two copies of vector - like leptons. of these, one copy is an $ su ( 2 ) _ l $ singlet while the other, an $ su ( 2 ) _ l $ doublet. we explain how this combination can offer a solution to the muon g - 2 anomaly and also lead to non - zero neutrino masses. in addition, it is also shown that the parameter regions compliant with the two aforementioned issues can stabilise the electroweak vacuum till the planck scale, something not possible within the standard model alone.
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arxiv:2010.05215
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the detection of gravitational waves ( gws ) by ground - based laser interferometer gw observatories ( ligo / virgo ) reveals a population of stellar binary black holes ( sbbhs ) with ( total ) masses up to $ \ sim 150m _ \ odot $, which are potential sources for space - based gw detectors, such as lisa and taiji. in this paper, we investigate in details on the possibility of detecting sbbhs by the lisa - taiji network in future. we adopt the sbbh merger rate density constrained by ligo / virgo observations to randomly generate mock sbbhs samples. assuming an observation period of $ 4 $ years, we find that the lisa - taiji network may detect several tens ( or at least several ) sbbhs with signal - to - noise ratio ( snr ) $ > 8 $ ( or $ > 15 $ ), a factor $ 2 - 3 $ times larger than that by only using lisa or taiji observations. among these sbbhs, no more than a few that can merge during the $ 4 $ - year observation period. if extending the observation period to $ 10 $ years, then the lisa - taiji network may detect about one hundred ( or twenty ) sbbhs with snr $ > 8 $ ( or $ > 15 $ ), among them about twenty ( or at least several ) can merge within the observation period. our results suggest that the lisa - taiji network may be able to detect at least a handful to twenty or more sbbhs even if assuming a conservative snr threshold ( $ 15 $ ) for ` ` detection ' ', which enables multi - band gw observations by space and ground - based gw detectors. we also further estimate the uncertainties in the parameter estimations of the sbbh systems ` ` detected ' ' by the lisa - taiji network. we find that the relative errors in the luminosity distance measurements and sky localization are mostly in the range of $ 0. 05 - 0. 2 $ and $ 1 - 100 \ deg ^ 2 $, respectively, for these sbbhs.
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arxiv:2201.12516
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core - satellite graphs ( sometimes referred to as generalized friendship graphs ) are an interesting class of graphs that generalize many well known types of graphs. in this paper we show that two popular clustering measures, the average watts - strogatz clustering coefficient and the transitivity index, diverge when the graph size increases. we also show that these graphs are disassortative. in addition, we completely describe the spectrum of the adjacency and laplacian matrices associated with core - satellite graphs. finally, we introduce the class of generalized core - satellite graphs, and we analyze the spectral properties of such graphs.
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arxiv:1510.07954
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recently a mechanism of storage ring operation based on the steady - state microbunching has been proposed and investigated, which contains a laser cavity modulator providing the longitudinal focusing for the circulating microbunches. in this paper we analyze the impact of the coherent undulator radiation on the longitudinal single - bunch multi - turn collective dynamics, exploring a new possible instability mechanism. we formulate the multi - turn equations of motion for the single microbunch as two sets of difference equations in the modulator and in the remaining storage ring. the dispersion equation can then be obtained by introduction of the undulator - averaged phase space coordinates. the predicted instability growth rate shows reasonable agreement with the numerical turn - by - turn tracking simulations provided validity of the underlying assumptions. the analysis shall provide some insights for the coherent undulator radiation driven multi - turn instability in the cavity modulator. differences between such a new instability mechanism and the robinson instability in a conventional radio - frequency - based storage ring are also discussed.
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arxiv:2205.15801
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we give a simple proof for recurrence of vertex reinforced jump process on \ ( \ mathbb { z } ^ d \ ), under strong reinforcement. moreover, we show how the previous result implies that linearly edge - reinforced random walk on \ \ ( \ mathbb { z } ^ d \ ) is { recurrent } for strong reinforcement. finally, we prove that the \ ( h ^ { ( 2 | 2 ) } \ ) model on \ ( \ mathbb { z } ^ d \ ) localizes at strong disorder. even though these results are well - known, we propose a unified approach, { which also has the advantage to provide shorter proofs }, and relies on estimating fractional moments, introduced by aizenman and molchanov.
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arxiv:1804.02739
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this work develops novel algorithms for high - performance networking in the presence of obstacles based on a method for communicating via ultrasonic rays reflected at the obstacles. the rays are curves determined by the variable speed of sound and initial conditions and we develop ultrasonic ray models based on a system of differential equations. we present new parallel algorithms and software for shape and trajectory reconstruction of moving obstacles and show how the reconstructed reflection point of a ray at an obstacle is a natural router for messages between the ray ' s transmitter and receiver and discuss the advantages of the new architecture. we discuss how the new algorithms and software improve the performance and properties of the network architecture.
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arxiv:1207.1520
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a set a is square - difference free ( henceforth sdf ) if there do not exist x, y \ in a, x \ ne y, such that | x - y | is a square. let sdf ( n ) be the size of the largest sdf subset of { 1,..., n }. ruzsa has shown that sdf ( n ) = \ omega ( n ^ { 0. 5 ( 1 + \ log _ { 65 } 7 ) } ) = \ omega ( n ^ { 0. 733077... } ) we improve on the lower bound by showing sdf ( n ) = \ omega ( n ^ { 0. 5 ( 1 + \ log _ { 205 } 12 ) } ) = \ omega ( n ^ {. 7443... } ) as a corollary we obtain a new lower bound on the quadratic van der waerden numbers.
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arxiv:0804.4892
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space - times admitting a 3 - dimensional lie group of conformal motions $ c _ 3 $ acting on null orbits are studied. coordinate expressions for the metric and the conformal killing vectors ( ckv ) are provided ( irrespectively of the matter content ) and then all possible perfect fluid solutions are found, although none of these verify the weak and dominant energy conditions over the whole space - time manifold.
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arxiv:gr-qc/9708020
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some solar - type stars are known to present faint, time - variable radio continuum emission whose nature is not clearly established. we report on jansky very large array observations of the nearby star $ \ epsilon $ eridani at 10. 0 and 33. 0 ghz. we find that this star has flux density variations on scales down to days, hours and minutes. on 2020 apr 15 it exhibited a radio pulse at 10. 0 ghz with a total duration of about 20 minutes and a peak four times larger than the plateau of 40 $ \ mu $ jy present in that epoch. we were able to model the time behavior of this radio pulse in terms of the radiation from shocks ramming into the stellar wind. such shocks can be produced by the wind interaction of violently expanding gas heated suddenly by energetic electrons from a stellar flare, similar to the observed solar flares. because of the large temperature needed in the working surface to produce the observed emission, this has to be non thermal. it could be gyrosynchrotron or synchrotron emission. unfortunately, the spectral index or polarization measurements from the radio pulse do not have enough signal - to - noise ratio to determine its nature.
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arxiv:2309.03862
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an optimization problem of content placement in cooperative caching is formulated, with the aim of maximizing sum mean opinion score ( mos ) of mobile users. firstly, a supervised feed - forward back - propagation connectionist model based neural network ( sfbc - nn ) is invoked for user mobility and content popularity prediction. more particularly, practical data collected from gps - tracker app on smartphones is tackled to test the accuracy of mobility prediction. then, a learning automata - based q - learning ( laql ) algorithm for cooperative caching is proposed, in which learning automata ( la ) is invoked for q - learning to obtain an optimal action selection in a random and stationary environment. it is proven that the la - based action selection scheme is capable of enabling every state to select the optimal action with arbitrarily high probability if q - learning is able to converge to the optimal q value eventually. to characterize the performance of the proposed algorithms, the sum mos of users is applied to define the reward function. extensive simulations reveal that : 1 ) the prediction error of sfbc - nn lessen with the increase of iterations and nodes ; 2 ) the proposed laql achieves significant performance improvement against traditional q - learning ; 3 ) the cooperative caching scheme is capable of outperforming non - cooperative caching and random caching of 3 % and 4 %.
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arxiv:1903.06235
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a major obstacle to implementing shor ' s quantum number - factoring algorithm is the large size of modular - exponentiation circuits. we reduce this bottleneck by customizing reversible circuits for modular multiplication to individual runs of shor ' s algorithm. our circuit - synthesis procedure exploits spectral properties of multiplication operators and constructs optimized circuits from the traces of the execution of an appropriate gcd algorithm. empirically, gate counts are reduced by 4 - 5 times, and circuit latency is reduced by larger factors.
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arxiv:1301.3210
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we investigate the potential of the international linear collider ( ilc ) to probe the mechanisms of neutrino mass generation and leptogenesis within the minimal seesaw model. our results can also be used as an estimate for the potential of a compact linear collider ( clic ). we find that heavy sterile neutrinos that simultaneously explain both, the observed light neutrino oscillations and the baryon asymmetry of the universe, can be found in displaced vertex searches at ilc. we further study the precision at which the flavour - dependent active - sterile mixing angles can be measured. the measurement of the ratios of these mixing angles, and potentially also of the heavy neutrino mass splitting, can test whether minimal type i seesaw models are the origin of the light neutrino masses, and it can be a first step towards probing leptogenesis as the mechanism of baryogenesis. our results show that the ilc can be used as a discovery machine for new physics in feebly coupled sectors that can address fundamental questions in particle physics and cosmology.
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arxiv:1801.06534
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we propose two algorithms to provide a full preliminary orbit of an earth - orbiting object with a number of observations lower than the classical methods, such as those by laplace and gauss. the first one is the virtual debris algorithm, based upon the admissible region, that is the set of the unknown quantities corresponding to possible orbits for objects in earth orbit ( as opposed to both interplanetary orbits and ballistic ones ). a similar method has already been successfully used in recent years for the asteroidal case. the second algorithm uses the integrals of the geocentric 2 - body motion, which must have the same values at the times of the different observations for a common orbit to exist. we also discuss how to account for the perturbations of the 2 - body motion, e. g., the $ j _ 2 $ effect.
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arxiv:0911.0149
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continuous engineering of autonomous driving functions commonly requires deploying vehicles in road testing to obtain inputs that cause problematic decisions. although the discovery leads to producing an improved system, it also challenges the foundation of testing using equivalence classes and the associated relative test coverage criterion. in this paper, we propose believed equivalence, where the establishment of an equivalence class is initially based on expert belief and is subject to a set of available test cases having a consistent valuation. upon a newly encountered test case that breaks the consistency, one may need to refine the established categorization in order to split the originally believed equivalence into two. finally, we focus on modules implemented using deep neural networks where every category partitions an input over the real domain. we present both analytical and lazy methods to suggest the refinement. the concept is demonstrated in analyzing multiple autonomous driving modules, indicating the potential of our proposed approach.
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arxiv:2103.04578
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we explore the structure of the ground state of $ ^ { 20 } $ ne by investigating various density profiles. four candidates for the ground state configurations, ( a ) $ j $ - $ j $ coupling and ( b ) su ( 3 ) shell model and ( c ) $ 5 \ alpha $ and ( d ) $ ^ { 16 } { \ rm o } + \ alpha $ cluster model configurations are generated by utilizing the antisymmetrized quasicluster model. a high - energy reaction theory, the glauber model, relates these one - body density distributions and reaction observables. the angular distributions of the elastic scattering cross sections clearly distinguish these configurations and tell which is the most plausible one : the ground state of $ ^ { 20 } $ ne favors a 16 + 4 nucleon bi - cluster structure. a comprehensive investigation of other electric observables also supports this conclusion.
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arxiv:2305.09182
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we propose a simple and effective cross - lingual transfer learning method to adapt monolingual wav2vec - 2. 0 models for automatic speech recognition ( asr ) in resource - scarce languages. we show that a monolingual wav2vec - 2. 0 is a good few - shot asr learner in several languages. we improve its performance further via several iterations of dropout uncertainty - driven self - training ( dust ) by using a moderate - sized unlabeled speech dataset in the target language. a key finding of this work is that the adapted monolingual wav2vec - 2. 0 achieves similar performance as the topline multilingual xlsr model, which is trained on fifty - three languages, on the target language asr task.
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arxiv:2110.03560
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in this paper, we provide the geometric formulation to the two - component camassa - holm equation ( 2 - mche ). we also study the relation between the 2 - mche and the m - cv equation. we have shown that these equations arise from the invariant space curve flows in three - dimensional euclidean geometry. using this approach we have established the geometrical equivalence between the 2 - mche and the m - cv equation. the gauge equivalence between these equations is also considered.
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arxiv:1908.01371
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validation of robotics theory on real - world hardware platforms is important to prove the practical feasibility of algorithms. this paper discusses some of the lessons learned while adapting the evobot, a low - cost robotics platform that we designed and prototyped, for research in diverse areas in robotics. the evobot platform was designed to be a low cost, open source, general purpose robotics platform intended to enable testing and validation of algorithms from a wide variety of sub - fields of robotics. throughout the paper, we outline and discuss some common failures, practical limitations and inconsistencies between theory and practice that one may encounter while adapting such low - cost platforms for robotics research. we demonstrate these aspects through four representative common robotics tasks - localization, real - time control, swarm consensus and path planning applications, performed using the evobots. we also propose some potential solutions to the encountered problems and try to generalize them.
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arxiv:1705.07231
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a brst perturbative analysis of su ( n ) yang - mills theory in a class of maximal abelian gauges is presented. we point out the existence of a new nonintegrated renormalizable ward identity which allows to control the dependence of the theory from the diagonal ghosts. this identity, called the diagonal ghost equation, plays a crucial role for the stability of the model under radiative corrections implying, in particular, the vanishing of the anomalous dimension of the diagonal ghosts. moreover, the ward identity corresponding to the abelian cartan subgroup is easily derived from the diagonal ghost equation. finally, a simple proof of the fact that the beta function of the gauge coupling can be obtained from the vacuum polarization tensor with diagonal gauge fields as external legs is given. a possible mechanism for the decoupling of the diagonal ghosts at low energy is also suggested.
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arxiv:hep-th/0105060
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an ever - increasing amount of social media content requires advanced ai - based computer programs capable of extracting useful information. specifically, the extraction of health - related content from social media is useful for the development of diverse types of applications including disease spread, mortality rate prediction, and finding the impact of diverse types of drugs on diverse types of diseases. language models are competent in extracting the syntactic and semantics of text. however, they face a hard time extracting similar patterns from social media texts. the primary reason for this shortfall lies in the non - standardized writing style commonly employed by social media users. following the need for an optimal language model competent in extracting useful patterns from social media text, the key goal of this paper is to train language models in such a way that they learn to derive generalized patterns. the key goal is achieved through the incorporation of random weighted perturbation and contrastive learning strategies. on top of a unique training strategy, a meta predictor is proposed that reaps the benefits of 5 different language models for discriminating posts of social media text into non - health and health - related classes. comprehensive experimentation across 3 public benchmark datasets reveals that the proposed training strategy improves the performance of the language models up to 3. 87 %, in terms of f1 - score, as compared to their performance with traditional training. furthermore, the proposed meta predictor outperforms existing health mention classification predictors across all 3 benchmark datasets.
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arxiv:2310.19057
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the present study reports the catalytic action of two - dimensional ( 2d ) layered materials ( mos2 and ws2 ) for improving the de / re - hydrogenation kinetics of mgh2. the mgh2 start desorbing at 277 c with a hydrogen storage capacity of 5. 95 wt % in the presence of ws2 catalyst whereas onset desorption temperature of mgh2 catalyzed by mos2 is 330 c. the mgh2 - ws2 absorbed hydrogen ~ 3. 72 wt % within 1. 3 minutes at 300 c under 13 atm hydrogen pressure and it desorbed ~ 5. 57 wt % within 20 minutes at 300 c under 1 atm hydrogen pressure. we have performed 25 cycles of dehydrogenation ( under 1 atm hydrogen pressure at 300 c ) and re - hydrogenation ( under 13 atm hydrogen pressure at 300 { \ deg } c ) to ensure cyclic stability of catalyzed version of mgh2 where mgh2 - ws2 shows better cyclic stability than mgh2 - mos2. mgh2 - ws2 also shows the lower reaction activation energy ~ 117 kj / mol as compare to other catalyzed and uncatalyzed samples. on the other hand, these catalysts ( ws2 and mos2 ) do not have any impact on the thermodynamical parameters that is change in enthalpy.
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arxiv:2301.02897
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as the role of information and communication technologies gradually increases in our lives, source code security becomes a significant issue to protect against malicious attempts furthermore with the advent of data - driven techniques, there is now a growing interest in leveraging machine learning and natural language processing as a source code assurance method to build trustworthy systems therefore training our future software developers to write secure source code is in high demand in this thesis we propose a framework including learning modules and hands on labs to guide future it professionals towards developing secure programming habits and mitigating source code vulnerabilities at the early stages of the software development lifecycle in this thesis our goal is to design learning modules with a set of hands on labs that will introduce students to secure programming practices using source code and log file analysis tools to predict and identify vulnerabilities in a secure coding education framework we will improve students skills and awareness on source code vulnerabilities detection tools and mitigation techniques integrate concepts of source code vulnerabilities from function api and library level to bad programming habits and practices leverage deep learning nlp and static analysis tools for log file analysis to introduce the root cause of source code vulnerabilities
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arxiv:2302.00750
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occurrence of room temperature ferromagnetism is demonstrated in pulsed laser deposited thin films of sn1 - xcoxo2 - d ( x < 0. 3 ). interestingly, films of sn0. 95co0. 05o2 - d grown on r - plane sapphire not only exhibit ferromagnetism with a curie temperature close to 650 k, but also a giant magnetic moment of about 7 bohr - magneton / co, not yet reported in any diluted magnetic semiconductor system. the films are semiconducting and optically highly transparent.
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arxiv:cond-mat/0301456
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methods for unsupervised domain adaptation ( uda ) help to improve the performance of deep neural networks on unseen domains without any labeled data. especially in medical disciplines such as histopathology, this is crucial since large datasets with detailed annotations are scarce. while the majority of existing uda methods focus on the adaptation from a labeled source to a single unlabeled target domain, many real - world applications with a long life cycle involve more than one target domain. thus, the ability to sequentially adapt to multiple target domains becomes essential. in settings where the data from previously seen domains cannot be stored, e. g., due to data protection regulations, the above becomes a challenging continual learning problem. to this end, we propose to use generative feature - driven image replay in conjunction with a dual - purpose discriminator that not only enables the generation of images with realistic features for replay, but also promotes feature alignment during domain adaptation. we evaluate our approach extensively on a sequence of three histopathological datasets for tissue - type classification, achieving state - of - the - art results. we present detailed ablation experiments studying our proposed method components and demonstrate a possible use - case of our continual uda method for an unsupervised patch - based segmentation task given high - resolution tissue images.
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arxiv:2302.01287
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wrinkling is a ubiquitous phenomenon in two - dimensional membranes. in particular, in the large - scale growth of graphene on metallic substrates, high densities of wrinkles are commonly observed. despite their prevalence and potential impact on large - scale graphene electronics, relatively little is known about their structural morphology and electronic properties. surveying the graphene landscape using atomic force microscopy, we found that wrinkles reach a certain maximum height before folding over. calculations of the energetics explain the morphological transition, and indicate that the tall ripples are collapsed into narrow standing wrinkles by van der waals forces, analogous to large - diameter nanotubes. quantum transport calculations show that conductance through these collapsed wrinkle structures is limited mainly by a density - of - states bottleneck and by interlayer tunneling across the collapsed bilayer region. also through systematic measurements across large numbers of devices with wide folded wrinkles, we find a distinct anisotropy in their electrical resistivity, consistent with our transport simulations. these results highlight the coupling between morphology and electronic properties, which has important practical implications for large - scale high - speed graphene electronics.
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arxiv:1207.2994
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while lhc has discovered a very standard model - like higgs boson of mass m _ h ~ 125 gev, no solid signal for physics beyond the standard model has emerged so far at lhc or at wimp seach experiments. for the case of weak scale supersymmetry ( susy ), lhc has found rather generally that gluinos are beyond about 2. 2 tev whilst top squark must lie beyond 1. 1 tev. these limits contradict older simplistic notions of naturalness that emerged in the 1980s - 1990s, leading to the rather pessimistic view that susy is now excluded except for perhaps some remaining narrow corners of parameter space. yet, this picture ignores several important developments in susy / string theory that emerged in the 21st century : 1. the emergence of the string theory landscape and its solution to the cosmological constant problem, 2. a more nuanced view of naturalness including the notion of " stringy naturalness ", 3. the emergence of anomaly - free discrete r - symmetries and their connection to r - parity, peccei - quinn symmetry, the susy mu problem and proton decay and 4. the importance of including a solution to the strong cp problem. rather general considerations from the string theory landscape favor large values of soft terms, subject to the vacuum selection criteria that electroweak symmetry is properly broken ( no ccb minima ) and the resulting magnitude of the weak scale is not too far from our measured value. then stringy naturalness predicts a higgs mass m _ h ~ 125 gev whilst sparticle masses are typically lifted beyond present lhc bounds. in light of these refinements in theory perspective confronted by lhc and dark matter search results, we review the most likely lhc, ilc and dark matter signatures that are expected to arise from weak scale susy as we understand it today.
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arxiv:2002.03013
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we aim to demonstrate that the presence and mass of an exoplanet can now be effectively derived from the astrometry of another exoplanet. we combined previous astrometry of $ \ beta $ pictoris b with a new set of observations from the gravity interferometer. the orbital motion of $ \ beta $ pictoris b is fit using markov chain monte carlo simulations in jacobi coordinates. the inner planet, $ \ beta $ pictoris c, was also reobserved at a separation of 96 \, mas, confirming the previous orbital estimations. from the astrometry of planet b only, we can ( i ) detect the presence of $ \ beta $ pictoris c and ( ii ) constrain its mass to $ 10. 04 ^ { + 4. 53 } _ { - 3. 10 } \, m _ { \ rm jup } $. if one adds the astrometry of $ \ beta $ pictoris c, the mass is narrowed down to $ 9. 15 ^ { + 1. 08 } _ { - 1. 06 } \, m _ { \ rm jup } $. the inclusion of radial velocity measurements does not affect the orbital parameters significantly, but it does slightly decrease the mass estimate to $ 8. 89 ^ { + 0. 75 } _ { - 0. 75 } \, m _ { \ rm jup } $. with a semimajor axis of $ 2. 68 \ pm0. 02 $ \, au, a period of $ 1221 \ pm15 $ days, and an eccentricity of $ 0. 32 \ pm0. 02 $, the orbital parameters of $ \ beta $ pictoris c are now constrained as precisely as those of $ \ beta $ pictoris b. the orbital configuration is compatible with a high - order mean - motion resonance ( 7 : 1 ). the impact of the resonance on the planets ' dynamics would then be negligible with respect to the secular perturbations, which might have played an important role in the eccentricity excitation of the outer planet.
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arxiv:2109.10671
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a quantitative analysis is presented for the stochastic interactions of a pair of brownian hard spheres in non - adsorbing polymer solutions. the hard spheres are hypothetically trapped by optical tweezers and allowed for random motion near the trapped positions. the investigation focuses on the long - time correlated brownian motion. the mobility tensor altered by the polymer depletion effect is computed by the boundary integral method, and the corresponding random displacement is determined by the fluctuation - dissipation theorem. from our computations it follows that the presence of depletion layers around the hard spheres has a significant effect on the hydrodynamic interactions and particle dynamics as compared to pure solvent and pure polymer solution ( no depletion ) cases. the probability distribution functions of random walks of the two interacting hard spheres that are trapped clearly shifts due to the polymer depletion effect. the results show that the reduction of the viscosity in the depletion layers around the spheres and the entropic force due to the overlapping of depletion zones have a significant influence on the correlated brownian interactions.
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arxiv:1401.8013
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we introduce a new method for estimating the parameter of the bivariate clayton copulas within the framework of algorithmic inference. the method consists of a variant of the standard boot - strapping procedure for inferring random parameters, which we expressly devise to bypass the two pitfalls of this specific instance : the non independence of the kendall statistics, customarily at the basis of this inference task, and the absence of a sufficient statistic w. r. t. \ alpha. the variant is rooted on a numerical procedure in order to find the \ alpha estimate at a fixed point of an iterative routine. although paired with the customary complexity of the program which computes them, numerical results show an outperforming accuracy of the estimates.
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arxiv:1910.02678
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we exploit an interpretation of gravity as the symmetry broken phase of a de sitter gauge theory to construct new solutions to the first order field equations. the new solutions are constructed by performing large $ spin ( 4, 1 ) $ gauge transformations on the ordinary de sitter solution and extracting first the tetrad, then the induced metric. the class of metrics so obtained is an infinite class labelled by an integer, $ q $. each solution satisfies the local field equations defining constant positive curvature, and is therefore locally isometric to de sitter space wherever the metric is non - degenerate. the degeneracy structure of the tetrad and metric reflects the topological differences among the solutions with different $ q $. by topological arguments we show that the solutions are physically distinct with respect to the symmetries of einstein - cartan theory. ultimately, the existence of solutions of this type may be a distinguishing characteristic of gravity as a metric theory versus gravity as a gauge theory.
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arxiv:0909.5435
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a search for the supersymmetric partners of quarks and gluons ( squarks and gluinos ) in final states containing jets and missing transverse momentum, but no electrons or muons, is presented. the data used in this search were recorded by the atlas experiment in proton - proton collisions at a centre - of - mass energy of $ \ sqrt { s } $ = 13 tev during run 2 of the large hadron collider, corresponding to an integrated luminosity of 139 fb $ ^ { - 1 } $. the results are interpreted in the context of various $ r $ - parity - conserving models where squarks and gluinos are produced in pairs or in association and a neutralino is the lightest supersymmetric particle. an exclusion limit at the 95 % confidence level on the mass of the gluino is set at 2. 30 tev for a simplified model containing only a gluino and the lightest neutralino, assuming the latter is massless. for a simplified model involving the strong production of mass - degenerate first - and second - generation squarks, squark masses below 1. 85 tev are excluded if the lightest neutralino is massless. these limits extend substantially beyond the region of supersymmetric parameter space excluded previously by similar searches with the atlas detector.
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arxiv:2010.14293
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a series of $ 1t $ - fe $ _ x $ ta $ _ { 1 - x } $ sse ( 0 $ \ leq x \ leq $ 0. 1 ) single crystals was fabricated via the chemical - vapor - transport ( cvt ) method and investigated by structure, transport, and magnetic measurements along with the density - functional - theory ( dft ) calculations. the superconductivity ( sc ) in parent $ 1t $ - tasse can be gradually suppressed by fe - substitution ( $ x \ leq0. 03 $ ), accompanied by the disappearance of charge - density - wave ( cdw ). dft calculations show that the fe - substitution effectively inhibits the cdw superstructure and thereby the cdw domains are destroyed. with further increasing $ x $ ( $ x > 0. 03 $ ), the disorder - induced scattering increases, and the system enters into the possible anderson localization ( al ) state. our results prove the sc develops in the cdw phase and coexists with the cdw domain in $ 1t $ - tasse system.
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arxiv:1406.5317
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a tangent category is a categorical abstraction of the tangent bundle construction for smooth manifolds. in that context, cockett and cruttwell develop the notion of differential bundle which, by work of macadam, generalizes the notion of smooth vector bundle to the abstract setting. here we provide a new characterization of differential bundles and show that, up to isomorphism, a differential bundle is determined by its projection map and zero section. we show how these results can be used to quickly identify differential bundles in various tangent categories.
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arxiv:2407.06515
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let $ k \ ge 2 $ and consider the sequence $ \ { p _ n ^ { ( k ) } \ } _ { n \ ge 2 - k } $ of $ k $ - generalized pell numbers, which begins with the first $ k $ terms as $ 0, \ ldots, 0, 0, 1 $, and satisfies the recurrence relation $ p _ n ^ { ( k ) } = 2p _ { n - 1 } ^ { ( k ) } + p _ { n - 2 } ^ { ( k ) } + \ cdots + p _ { n - k } ^ { ( k ) } $ for all $ n \ ge 2 $. in this work, we identify all terms in the $ k $ - pell sequence that can be expressed as palindromes formed by concatenating two distinct repdigits.
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arxiv:2504.14261
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frailty and resilience models provide a way to introduce random effects in hazard and reversed hazard rate modeling by random variables, called frailty and resilience random variables, respectively, to account for unobserved or unexplained heterogeneity among experimental units. this paper investigates the effects of frailty and resilience random variables on the baseline random variables using some shifted stochastic orders based on some ageing properties of the baseline random variables. relevant examples are provided to illustrate the results. some results are illustrated with real - world data.
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arxiv:2209.08261
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convolutional neural networks ( cnns ) were the driving force behind many advancements in computer vision research in recent years. this progress has spawned many practical applications and we see an increased need to efficiently move cnns to embedded systems today. however traditional cnns lack the property of scale and rotation invariance : two of the most frequently encountered transformations in natural images. as a consequence cnns have to learn different features for same objects at different scales. this redundancy is the main reason why cnns need to be very deep in order to achieve the desired accuracy. in this paper we develop an efficient solution by reproducing how nature has solved the problem in the human brain. to this end we let our cnn operate on small patches extracted using the log - polar transform, which is known to be scale and rotation equivariant. patches extracted in this way have the nice property of magnifying the central field and compressing the periphery. hence we obtain local descriptors with global context information. however the processing of a single patch is usually not sufficient to achieve high accuracies in e. g. classification tasks. we therefore successively jump to several different locations, called saccades, thus building an understanding of the whole image. since log - polar patches contain global context information, we can efficiently calculate following saccades using only the small patches. saccades efficiently compensate for the lack of translation equivariance of the log - polar transform.
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arxiv:2005.05701
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universal embezzlers are bipartite quantum systems from which any entangled state may be extracted to arbitrary precision using local operations while perturbing the state of the system arbitrarily little. here, we show that universal embezzlers are ubiquitous in many - body physics : the ground state sector of every local, translation - invariant, and critical free - fermionic many - body system on a one - dimensional lattice is a universal embezzler if bi - partitioned into two half - chains. the same property holds in locally - interacting, dual spin chains via the jordan - wigner transformation. universal embezzlement manifests already for finite system sizes, not only in the thermodynamic limit : for any finite error and any targeted entangled state, a finite length of the chain is sufficient to embezzle said state within the given error. on a technical level, our main result establishes that the half - chain observable algebras associated with ground state sectors of the given models are type iii $ _ 1 $ factors.
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arxiv:2406.11747
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the classification of riemannian manifolds by the holonomy group of their levi - civita connection picks out many interesting classes of structures, several of which are solutions to the einstein equations. the classification has two parts. the first consists of isolated examples : the riemannian symmetric spaces. the second consists of geometries that can occur in continuous families : these include the calabi - yau structures and joyce manifolds of string theory. one may ask how one can weaken the definitions and still obtain similar classifications. we present two closely related suggestions. the classifications for these give isolated examples that are isotropy irreducible spaces, and known families that are the nearly k \ " ahler manifolds in dimension 6 and gray ' s weak holonomy g $ _ 2 $ structures in dimension 7.
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arxiv:math/0211446
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we study a cooperation model where the positions of base stations follow a poisson point process distribution and where voronoi cells define the planar areas associated with them. for the service of each user, either one or two base stations are involved. if two, these cooperate by exchange of user data and reduced channel information ( channel phase, second neighbour interference ) with conferencing over some backhaul link. the total user transmission power is split between them and a common message is encoded, which is coherently transmitted by the stations. the decision for a user to choose service with or without cooperation is directed by a family of geometric policies. the suggested policies further control the shape of coverage contours in favor of cell - edge areas. analytic expressions based on stochastic geometry are derived for the coverage probability in the network. their numerical evaluation shows benefits from cooperation, which are enhanced when dirty paper coding is applied to eliminate the second neighbour interference.
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arxiv:1311.5362
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believed that the earth was flat and surrounded by water. herodotus in his histories ridiculed the belief that water encircled the world, yet most classicists agree that he still believed earth was flat because of his descriptions of literal " ends " or " edges " of the earth. = = = = northern europe = = = = the ancient norse and germanic peoples believed in a flat - earth cosmography with the earth surrounded by an ocean, with the axis mundi, a world tree ( yggdrasil ), or pillar ( irminsul ) in the centre. in the world - encircling ocean sat a snake called jormungandr. the norse creation account preserved in gylfaginning ( viii ) states that during the creation of the earth, an impassable sea was placed around it : and jafnharr said : " of the blood, which ran and welled forth freely out of his wounds, they made the sea, when they had formed and made firm the earth together, and laid the sea in a ring round. about her ; and it may well seem a hard thing to most men to cross over it. " the late norse konungs skuggsja, on the other hand, explains earth ' s shape as a sphere : if you take a lighted candle and set it in a room, you may expect it to light up the entire interior, unless something should hinder, though the room be quite large. but if you take an apple and hang it close to the flame, so near that it is heated, the apple will darken nearly half the room or even more. however, if you hang the apple near the wall, it will not get hot ; the candle will light up the whole house ; and the shadow on the wall where the apple hangs will be scarcely half as large as the apple itself. from this you may infer that the earth - circle is round like a ball and not equally near the sun at every point. but where the curved surface lies nearest the sun ' s path, there will the greatest heat be ; and some of the lands that lie continuously under the unbroken rays cannot be inhabited. = = = = east asia = = = = in ancient china, the prevailing belief was that the earth was flat and square, while the heavens were round, an assumption virtually unquestioned until the introduction of european astronomy in the 17th century. the english sinologist cullen emphasizes the point that there was no concept of a round earth in
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https://en.wikipedia.org/wiki/Flat_Earth
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heath and pemmaraju conjectured that the queue - number of a poset is bounded by its width and if the poset is planar then also by its height. we show that there are planar posets whose queue - number is larger than their height, refuting the second conjecture. on the other hand, we show that any poset of width $ 2 $ has queue - number at most $ 2 $, thus confirming the first conjecture in the first non - trivial case. moreover, we improve the previously best known bounds and show that planar posets of width $ w $ have queue - number at most $ 3w - 2 $ while any planar poset with $ 0 $ and $ 1 $ has queue - number at most its width.
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arxiv:1806.04489
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we give new homotopy theoretic criteria for deciding when a fibration with homotopy finite fibers admits a reduction to a fiber bundle with compact topological manifold fibers. the criteria lead to a new and unexpected result about homeomorphism groups of manifolds. a tool used in the proof is a surjective splitting of the assembly map for waldhausen ' s functor a ( x ). we also give concrete examples of fibrations having a reduction to a fiber bundle with compact topological manifold fibers but which fail to admit a compact fiber smoothing. the examples are detected by algebraic k - theory invariants. we consider a refinement of the becker - gottlieb transfer. we show that a version of the axioms described by becker and schultz uniquely determines the refined transfer for the class of fibrations admitting a reduction to a fiber bundle with compact topological manifold fibers. in an appendix, we sketch a theory of characteristic classes for fibrations. the classes are primary obstructions to finding a compact fiber smoothing.
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arxiv:0707.0250
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we study the joint spectral properties of photon pairs generated by spontaneous parametric down - conversion in a one - dimensional nonlinear photonic crystal in a collinear, degenerate, type - ii geometry. we show that the photonic crystal properties may be exploited to compensate for material dispersion and obtain photon pairs that are nearly factorable, in principle, for arbitrary materials and spectral regions, limited by the ability to fabricate the nonlinear crystal with the required periodic variation in the refractive indices for the ordinary and extraordinary waves.
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arxiv:0710.3745
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in this article we address a well known problem at the intersection of ergodic theory and statistical mechanics. we prove that there exists a continuous eigenfunction for the transfer operator corresponding to pair potentials that satisfy a square summability condition on the variations, when the inverse temperature is subcritical. as a corollary we obtain a continuous eigenfunction for the classical dyson model, with interactions $ \ j ( k ) = \ beta \, k ^ { - \ alpha } $, $ k \ ge1 $, in the whole subcritical regime $ \ beta < \ beta _ c $ for which the parameter $ \ alpha $ is greater than $ 3 / 2 $.
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arxiv:2304.04202
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cosmic voids and their corresponding redshift - projected mass densities, known as troughs, play an important role in our attempt to model the large - scale structure of the universe. understanding these structures enables us to compare the standard model with alternative cosmologies, constrain the dark energy equation of state, and distinguish between different gravitational theories. in this paper, we extend the subspace - constrained mean shift algorithm, a recently introduced method to estimate density ridges, and apply it to 2d weak lensing mass density maps from the dark energy survey y1 data release to identify curvilinear filamentary structures. we compare the obtained ridges with previous approaches to extract trough structure in the same data, and apply curvelets as an alternative wavelet - based method to constrain densities. we then invoke the wasserstein distance between noisy and noiseless simulations to validate the denoising capabilities of our method. our results demonstrate the viability of ridge estimation as a precursor for denoising weak lensing observables to recover the large - scale structure, paving the way for a more versatile and effective search for troughs.
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arxiv:2005.08583
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we show direct formal relationship between the wang - landau iteration [ prl 86, 2050 ( 2001 ) ], metadynamics [ pnas 99, 12562 ( 2002 ) ] and statistical temperature molecular dynamics [ prl 97, 050601 ( 2006 ) ], the major monte carlo and molecular dynamics work - horses for sampling from a generalized, multicanonical ensemble. we demonstrate that statistical temperature molecular dynamics ( which is formally derived from the wang - landau method ), augmented by the introduction of kernel updates of the statistical temperature, generates dynamics which are indistinguishable from a corresponding metadynamics simulation. we also show that the use of a gaussian kernel significantly improves the performance of statistical temperature molecular dynamics, highlighting the practical benefits of this improved formal understanding.
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arxiv:1401.6184
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a number of mechanisms have been proposed to connect star - forming dwarf irregular galaxies with the formation of non - star - forming dwarf spheroidal galaxies, but distinguishing between these mechanisms has been difficult. we use the via lactea dark matter only cosmological simulations to test two well - motivated simple hypotheses - - - transformation of irregulars into dwarf spheroidal galaxies by tidal stirring and ram pressure stripping following a close passage to the host galaxy, and transformation via mergers between dwarfs - - - and predict the radial distribution and inferred formation times of the resulting dwarf spheroidal galaxies. we compare this to the observed distribution in the local group and show that 1 ) the observed dsph distribution far from the galaxy or m31 can be matched by the vl halos that have passed near the host galaxy at least once, though significant halo - to - halo scatter exists, 2 ) models that require two or more pericenter passages for dsph - formation cannot account for the dsphs beyond 500 kpc such as cetus and tucana, and 3 ) mergers predict a flat radial distribution of dsphs and cannot account for the high dsph fraction near the galaxy, but are not ruled out at large distances. the models also suggest that for dsphs found today beyond 500 kpc, mergers tend to occur significantly earlier than dwarf - - host encounters, thus leading to a potentially observable difference in stellar populations. we argue that tidal interactions are sufficient to reproduce the observed distribution of dsphs if and only if a single pericenter passage is sufficient to form a dsph.
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arxiv:1306.1829
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current measurements of the weak lensing signal induced by large scale structure provide useful constraints on a range of cosmological parameters. however, the ultimate succes of this technique depends on the accuracy with which one can correct for the effect of the point spread function ( psf ). in this paper we examine the accuracy of the psf anisotropy correction using images of fields with a large number of stars. the ellipticity correlation function of the residuals is studied to quantify the effect of imperfect corrections for psf anisotropy on cosmic shear studies. these imperfections occur on the chip scale and consequently the systematic signal decreases rapidly with increasing angular scale. separation of the signal into ` ` e ' ' ( curl - free ) and ` ` b ' ' ( curl ) components can help to identify the presence of residual systematics, but in general, the amplitude of the ` ` b ' ' - mode is different from that of the ` ` e ' ' - mode. the study of fields with many stars can be beneficial in finding a proper description of the variation of psf anisotropy, and consequently help to significantly improve the accuracy with which the cosmic shear signal can be measured. we show that with such an approach it is feasible that the accuracy of future cosmic shear studies is limited by the statistical noise introduced by the intrinsic shapes of the sources. in particular, the prospects for accurate measurements of the cosmic shear signal on scales larger than ~ 10 arcminutes are excellent.
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arxiv:astro-ph/0306097
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within a field theoretical model where all damping width effects are treated self - consistently we study the changes of the spectral properties of rho - mesons due to the finite damping width of the pions in dense hadronic matter at finite temperature. the corresponding effects in the di - lepton yields are presented. some problems concerning the self consistent treatment of vector or gauge bosons are discussed.
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arxiv:hep-ph/0002087
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ensuring ai safety is crucial as large language models become increasingly integrated into real - world applications. a key challenge is jailbreak, where adversarial prompts bypass built - in safeguards to elicit harmful disallowed outputs. inspired by psychological foot - in - the - door principles, we introduce fitd, a novel multi - turn jailbreak method that leverages the phenomenon where minor initial commitments lower resistance to more significant or more unethical transgressions. our approach progressively escalates the malicious intent of user queries through intermediate bridge prompts and aligns the model ' s response by itself to induce toxic responses. extensive experimental results on two jailbreak benchmarks demonstrate that fitd achieves an average attack success rate of 94 % across seven widely used models, outperforming existing state - of - the - art methods. additionally, we provide an in - depth analysis of llm self - corruption, highlighting vulnerabilities in current alignment strategies and emphasizing the risks inherent in multi - turn interactions. the code is available at https : / / github. com / jinxiaolong1129 / foot - in - the - door - jailbreak.
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arxiv:2502.19820
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resonant power converters offer improved levels of efficiency and power density. in order to implement such systems, advanced control techniques are required to take the most of the power converter. in this context, model predictive control arises as a powerful tool that is able to consider nonlinearities and constraints, but it requires the solution of complex optimization problems or strong simplifying assumptions that hinder its application in real situations. motivated by recent theoretical advances in the field of deep learning, this paper proposes to learn, offline, the optimal control policy defined by a complex model predictive formulation using deep neural networks so that the online use of the learned controller requires only the evaluation of a neural network. the obtained learned controller can be executed very rapidly on embedded hardware. we show the potential of the presented approach on a hardware - in - the - loop setup of an fpga - controlled resonant power converter.
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arxiv:1810.04872
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due to its high mass and short lifetime, the top quark plays an important role in checking the standard model of particle physics. in this report, we pr \ esent a variety of searches for physics beyond the standard model, involving top quarks, at the d0 detector at the fermilab tevatron collider. specifically, we present searches in top quark pair production, single top quark production and top quark decays. the search spectra discussed here involve a search for $ t \ bar { t } $ resonances, associated production of higgs bosons and $ t \ bar { t } $, charged higgs bosons and heavy gauge $ w ^ { ' } $ bosons. furthermore, we measure the forward - backward charge asymmetry and a ratio of branching fractions.
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arxiv:1004.1732
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we analyze cross - correlations between price fluctuations of different stocks using methods of random matrix theory ( rmt ). using two large databases, we calculate cross - correlation matrices c of returns constructed from ( i ) 30 - min returns of 1000 us stocks for the 2 - yr period 1994 - - 95 ( ii ) 30 - min returns of 881 us stocks for the 2 - yr period 1996 - - 97, and ( iii ) 1 - day returns of 422 us stocks for the 35 - yr period 1962 - - 96. we test the statistics of the eigenvalues $ \ lambda _ i $ of c against a ` ` null hypothesis ' ' - - - a random correlation matrix constructed from mutually uncorrelated time series. we find that a majority of the eigenvalues of c fall within the rmt bounds $ [ \ lambda _ -, \ lambda _ + ] $ for the eigenvalues of random correlation matrices. we test the eigenvalues of c within the rmt bound for universal properties of random matrices and find good agreement with the results for the gaussian orthogonal ensemble of random matrices - - - implying a large degree of randomness in the measured cross - correlation coefficients. further, we find that the distribution of eigenvector components for the eigenvectors corresponding to the eigenvalues outside the rmt bound display systematic deviations from the rmt prediction. in addition, we find that these ` ` deviating eigenvectors ' ' are stable in time. we analyze the components of the deviating eigenvectors and find that the largest eigenvalue corresponds to an influence common to all stocks. our analysis of the remaining deviating eigenvectors shows distinct groups, whose identities correspond to conventionally - identified business sectors. finally, we discuss applications to the construction of portfolios of stocks that have a stable ratio of risk to return.
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arxiv:cond-mat/0108023
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we derive parts of the monopole and dyon spectra for n = 2 super - yang - - mills theories in four dimensions with gauge groups g of rank r > 1 and matter multiplets. special emphasis is put on g = su ( 3 ) and those matter contents that yield perturbatively finite theories. there is no direct interpretation of the soliton spectra in terms of naive selfduality under strong - - weak coupling and exchange of electric and magnetic charges. we argue that, in general, the standard procedure of finding the dyon spectrum will not give results that support a conventional selfduality hypothesis - - - the su ( 2 ) theory with four fundamental hypermultiplets seems to be an exception. possible interpretations of the results are discussed.
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arxiv:hep-th/9603134
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notions of graph similarity provide alternative perspective on the graph isomorphism problem and vice - versa. in this paper, we consider measures of similarity arising from mismatch norms as studied in gervens and grohe : the edit distance $ \ delta _ { \ mathcal { e } } $, and the metrics arising from $ \ ell _ p $ - operator norms, which we denote by $ \ delta _ p $ and $ \ delta _ { | p | } $. we address the following question : can these measures of similarity be used to design polynomial - time approximation algorithms for graph isomorphism? we show that computing an optimal value of $ \ delta _ { \ mathcal { e } } $ is \ np - hard on pairs of graphs with the same number of edges. in addition, we show that computing optimal values of $ \ delta _ p $ and $ \ delta _ { | p | } $ is \ np - hard even on pairs of $ 1 $ - planar graphs with the same degree sequence and bounded degree. these two results improve on previous known ones, which did not examine the restricted case where the pairs of graphs are required to have the same number of edges. finally, we study similarity problems on strongly regular graphs and prove some near optimal inequalities with interesting consequences on the computational complexity of graph and group isomorphism.
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arxiv:2309.03810
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pion exchange in s - wave between hadrons that are themselves in a relative s - wave can shift energies by hundreds of mev. in the case of charmed mesons $ d, d ^ *, d _ 0, d _ 1 $ a spectroscopy of quasi - molecular states may arise consistent with enigmatic charmonium states observed above 4 gev in $ e ^ + e ^ - $ annihilation. a possible explanation of $ y ( 4260 ) \ to \ psi \ pi \ pi $ and $ y ( 4360 ) \ to \ psi ' \ pi \ pi $ is found. searches in $ d \ bar { d } 3 \ pi $ channels as well as b decays are recommended to test this hypothesis.
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arxiv:0905.2687
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we discuss long - baseline neutrino oscillations in the framework of the two 4 - neutrino schemes which can accommodate all existing neutrino oscillation data. negative results of short - baseline reactor and accelerator experiments allow to obtain rather strong bounds on the long - baseline nu _ e - > nu _ e and nu _ mu - > nu _ e transition probabilities. we consider in detail matter effects and show that the vacuum bounds are not substantially modified. we also comment on corresponding bounds in 3 - neutrino scenarios.
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arxiv:hep-ph/9710209
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this paper is interested in the description of the density of particles evolving according to some optimal policy of an impulse control problem. we first fix sets on which the particles jump and explain how we can characterize such a density. we then investigate the coupled case in which the underlying impulse control problem depends on the density we are looking for : the mean field games of impulse control. in both cases, we give a variational characterization of the densities of jumping particles.
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arxiv:1803.06126
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we show that superconductors with broken time - reversal symmetry have very specific magnetic and electric responses to inhomogeneous heating. a local heating of such superconductors induces a magnetic field with a profile that is sensitive to the presence of domain walls and crystalline anisotropy of superconducting states. a nonstationary heating process produces an electric field and a charge imbalance in different bands. these effects can be measured and used to distinguish $ s + is $ and $ s + id $ superconducting states in the candidate materials such as ba $ _ { 1 - x } $ k $ _ x $ fe $ _ 2 $ as $ _ 2 $.
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arxiv:1507.04712
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we study the boundary behaviour of a variant of the fridman ' s invariant function ( defined in terms of the bergman metric ) on levi corank one domains, strongly pseudoconvex domains, smoothly bounded convex domains in $ \ mathbb { c } ^ n $ and polyhedral domains in $ \ mathbb { c } ^ 2 $.
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arxiv:2312.16111
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a major challenge in next - generation industrial applications is to improve numerical analysis by quantifying uncertainties in predictions. in this work we present a formulation of a fully nonlinear and dispersive potential flow water wave model with random inputs for the probabilistic description of the evolution of waves. the model is analyzed using random sampling techniques and non - intrusive methods based on generalized polynomial chaos ( pc ). these methods allow to accurately and efficiently estimate the probability distribution of the solution and require only the computation of the solution in different points in the parameter space, allowing for the reuse of existing simulation software. the choice of the applied methods is driven by the number of uncertain input parameters and by the fact that finding the solution of the considered model is computationally intensive. we revisit experimental benchmarks often used for validation of deterministic water wave models. based on numerical experiments and assumed uncertainties in boundary data, our analysis reveals that some of the known discrepancies from deterministic simulation in comparison with experimental measurements could be partially explained by the variability in the model input. we finally present a synthetic experiment studying the variance based sensitivity of the wave load on an off - shore structure to a number of input uncertainties. in the numerical examples presented the pc methods have exhibited fast convergence, suggesting that the problem is amenable to being analyzed with such methods.
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arxiv:1410.6338
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in their paper from 1981, milner and sauer conjectured that for any poset p, if cf ( p ) = lambda > cf ( lambda ) = kappa, then p must contain an antichain of size kappa. we prove that for lambda > cf ( lambda ) = kappa, if there exists a cardinal mu < lambda such that cov ( lambda, mu, kappa, 2 ) = lambda, then any poset of cofinality lambda contains lambda ^ kappa antichains of size kappa. the hypothesis of our theorem is very weak and is a consequence of many well - known axioms such as gch, ssh and pfa. the consistency of the negation of this hypothesis is unknown.
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arxiv:math/0606021
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we propose a scheme for distributing continuous variable entanglement originally established among a pair of mode between a set of four orthogonal co - propagating modes. this is accomplished by exploiting the possibility of coupling polarization with optical angular momentum provided by the q - plate. here we present the principle of the proposed scheme with a short feasibility study that shows that the four - modes covariance matrix at the scheme output represent an entangled multi mode system.
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arxiv:1811.08388
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graviton - photon conversions in a given external electric or magnetic field, known as the gertsenshtein mechanism, are usually treated using the four - potential for photons. in terms of the electric and magnetic ( em ) fields, however, proper identification of the fields in curved spacetime is important. by misidentifying the fields in minkowski form, as is often practiced in the literature, we show that the final equation for photon conversion is correct in transverse - tracefree gauge only for planar gravitational waves in a uniform and constant external field. even in the former method, to recover the em fields from the four - potential in curved spacetime, one should properly take into account the metric involved in the relation. by including the metric perturbation in the graviton conversion equation, we show that a magnetic environment can cause tachyonic instability term in gravitational wave equation.
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arxiv:2310.04150
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we discuss the universal dynamics of elastic interfaces in quenched random media. we focus in the relation between the rough geometry and collective transport properties in driven steady - states. specially devised numerical algorithms allow us to analyze the equilibrium, creep, and depinning regimes of motion in minimal models. the relevance of our results for understanding domain wall experiments is outlined.
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arxiv:1304.0119
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substantial temperature and cr pressure differences between our grey and spectral cr models.
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arxiv:2303.03417
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dynamically probing systems of ultrastrongly coupled light and matter by advanced coherent control has been recently proposed as a unique tool for detecting peculiar quantum features of this regime. coherence allows in principle on - demand conversion of virtual photons dressing the entangled eigenstates of the system to real ones, with unitary efficiency and remarkable robustness. here we study this effect in the presence of decoherence, showing that also in far from ideal regimes is it possible to probe such peculiar features.
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arxiv:2101.12545
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in this study, we explore the efficacy of advanced pre - trained architectures, such as vision transformers ( vit ), convnext, and swin transformers in enhancing federated domain generalization. these architectures capture global contextual features and model long - range dependencies, making them promising candidates for improving cross - domain generalization. we conduct a broad study with in - depth analysis and systematically evaluate different variants of these architectures, using extensive pre - training datasets such as imagenet - 1k, imagenet - 21k, jft - 300m, and imagenet - 22k. additionally, we compare self - supervised and supervised pre - training strategies to assess their impact on fdg performance. our findings suggest that self - supervised techniques, which focus on reconstructing masked image patches, can better capture the intrinsic structure of images, thereby outperforming their supervised counterparts. comprehensive evaluations on the office - home and pacs datasets demonstrate that adopting advanced architectures pre - trained on larger datasets establishes new benchmarks, achieving average accuracies of 84. 46 \ % and 92. 55 \ %, respectively. additionally, we observe that certain variants of these advanced models, despite having fewer parameters, outperform larger resnet models. this highlights the critical role of utilizing sophisticated architectures and diverse pre - training strategies to enhance fdg performance, especially in scenarios with limited computational resources where model efficiency is crucial. our results indicate that federated learning systems can become more adaptable and efficient by leveraging these advanced methods, offering valuable insights for future research in fdg.
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arxiv:2409.13527
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dirac materials are characterized by energy - momentum relations that resemble those of relativistic massless particles. commonly denominated dirac cones, these dispersion relations are considered to be their essential feature. these materials comprise quite diverse examples, such as graphene and topological insulators. band - engineering techniques should aim to a full control of the parameter that characterizes the dirac cones : the fermi velocity. we propose a general mechanism that enables the fine - tuning of the fermi velocity in dirac materials in a readily accessible way for experiments. by embedding the sample in a uniform electric field, the fermi velocity is substantially modified. we first prove this result analytically, for the surface states of a topological insulator / semiconductor interface, and postulate its universality to other dirac materials. then we check its correctness in carbon - based dirac materials, namely graphene nanoribbons and nanotubes, thus showing the validity of our hypothesis in both continuum and tight - binding calculations and in different dirac systems.
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arxiv:1702.08296
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the solar granulation is known for a long time to be a surface manifestation of convection. thanks to the current space - borne missions corot and kepler, it is now possible to observe in disk - integrated intensity the signature of this phenomena in a growing number of stars. the space - based photometric measurements show that the global brightness fluctuations and the lifetime associated with granulation obeys characteristic scaling relations. we thus aim at providing a simple theoretical modeling to reproduce these scaling relations and subsequently at inferring the physical properties of granulation properties across the hr diagram. we develop a simple 1d theoretical model that enable us to test any prescription concerning the time - correlation between granules. the input parameters of the model are extracted from 3d hydrodynamical models of the surface layers of stars, and the free parameters involved in the model are calibrated with solar observations. two different prescriptions for representing the eddy time - correlation in the fourier space are compared : a lorentzian and an exponential form. finally, we compare our theoretical prediction with a 3d radiative hydrodynamical ( rhd ) numerical modeling of stellar granulation ( ab - initio approach ). provided that the free parameters are appropriately adjusted, our theoretical model satisfactorily reproduces the shape and the amplitude of the observed solar granulation spectrum. the best agreement is obtained with an exponential form. furthermore, our theoretical model results in granulation spectra that consistently agree with the these calculated on the basis of the ab - initio approach with two 3d rhd models. comparison between theoretical granulation spectra calculated with the present model and high precision photometry measurements of stellar granulation is undertaken in a companion paper.
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arxiv:1309.1620
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ultra - cold atoms in optical lattices provide an ideal platform for exploring many - body physics of a large system arising from the coupling among a series of small identical systems whose few - body dynamics is exactly solvable. using landau - zener ( lz ) transition of bosonic atoms in double well optical lattices as an experimentally realizable model, we investigate such few to many body route by exploring the relation and difference between the small few - body ( in one double well ) and the large many - body ( in double well lattice ) non - equilibrium dynamics of cold atoms in optical lattices. we find the many - body coupling between double wells greatly enhances the lz transition probability. the many - body dynamics in the double well lattice shares both similarity and difference from the few - body dynamics in one and two double wells. the sign of the on - site interaction plays a significant role on the many - body lz transition. various experimental signatures of the many - body lz transition, including atom density, momentum distribution, and density - density correlation, are obtained.
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arxiv:1110.1653
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sensing and communications ( s & c ) have been historically developed in parallel. in recent decade, they have been evolving from separation to integration, giving rise to the integrated sensing and communications ( isac ) paradigm, that has been recognized as one of the six key 6g usage scenarios. despite the plethora of research works dedicated to isac signal processing, the fundamental performance limits of s & c remain widely unexplored in an isac system. in this tutorial paper, we attempt to summarize the recent research findings in characterizing the performance boundary of isac systems and the resulting s & c tradeoff from an information - theoretical viewpoint. we begin with a folklore " torch metaphor " that depicts the resource competition mechanism of s & c. then, we elaborate on the fundamental capacity - distortion ( c - d ) theory, indicating the incompleteness of this metaphor. towards that end, we further elaborate on the s & c tradeoff by discussing a special case within the c - d framework, namely the cramer - rao bound ( crb ) - rate region. in particular, s & c have preference discrepancies over both the subspace occupied by the transmitted signal and the adopted codebook, leading to a " projector metaphor " complementary to the isac torch analogy. we also present two practical design examples by leveraging the lessons learned from fundamental theories. finally, we conclude the paper by identifying a number of open challenges.
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arxiv:2310.09749
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we address the problem of the minus sign sampling for two electron systems using the path integral approach. we show that this problem can be reexpressed as one of computing free energy differences and sampling the tails of statistical distributions. using metadynamics, a realistic problem like that of two electrons confined in a quantum dot can be solved. we believe that this is a strategy that can possibly be extended to more complex systems.
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arxiv:1805.01678
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we introduce a generalized notion of finiteness that provides a structural principle for the set of effective theories that can be consistently coupled to quantum gravity. more concretely, we propose a tameness conjecture that states that all valid effective theories are labelled by a definable parameter space and must have scalar field spaces and coupling functions that are definable using the tame geometry built from an o - minimal structure. we give a brief introduction to tame geometry and describe how it restricts sets, manifolds, and functions. we then collect evidence for the tameness conjecture by studying various effective theories arising from string theory compactifications by using some recent advances in tame geometry. in particular, we will exploit the fact that coset spaces and period mappings are definable in an o - minimal structure and argue for non - trivial tameness results in higher - supersymmetric theories and in calabi - yau compactifications. as strongest evidence for the tameness conjecture over a discrete parameter space, we then discuss a recent theorem stating that the locus of self - dual flux vacua of f - theory admits a tame geometry even if one allows for any flux choice satisfying the tadpole constraint. this result implies the finiteness of self - dual flux vacua in f - theory.
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arxiv:2112.08383
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in this paper, we consider finite isospin chiral perturbation theory including the effects of the axial anomaly ( through the wess - zumino - witten term ) in a strong magnetic field. we firstly prove that in a strong external magnetic field ( $ h _ { \ rm ext } $ ) or more precisely the schwinger limit, where photon back - reactions are suppressed, only neutral pions can condense and the condensation of charged pions is forbidden. secondly, we find that the $ \ pi ^ { 0 } $ domain wall is an example of a phase that can exist in a strong magnetic field and suggest the existence of a new phase transition line from the normal vacuum state to the $ \ pi ^ { 0 } $ domain wall state. this phase transition exists for non - zero pion masses if the baryon chemical potential exceeds a critical value $ 16 \ pi f _ { \ pi } ^ { 2 } m _ { \ pi } / eh _ { \ rm ext } $. the phase transition line persists away from the schwinger limit when the photons can back - react to the external magnetic field.
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arxiv:1504.06349
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a lower bound on the amount of energy needed to carry out an elementary logical operation on a qubit system, with a given accuracy and in a given time, has been recently postulated. this paper is an attempt to formalize this bound and explore the conditions under which it may be expected to hold. this is a work in progress and any contributions will be appreciated.
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arxiv:quant-ph/0209065
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the well studied blazar 3c 279 underwent a giant $ \ gamma $ - ray outburst in 2014 march - april. the measured $ \ gamma $ - ray flux ( 1. 21 $ \ pm $ 0. 10 $ \ times $ 10 $ ^ { - 5 } $ ph cm $ ^ { - 2 } $ s $ ^ { - 1 } $ in 0. 1 - 300 gev energy range ) is the highest detected from 3c 279 by fermi large area telescope. hour scale $ \ gamma $ - ray flux variability are observed, with a flux doubling time as short as 1. 19 $ \ pm $ 0. 36 hours detected during one flare. the $ \ gamma $ - ray spectrum is found to be curved at peak of the flare suggesting low probability of detecting very high energy ( vhe ; e $ > $ 100 gev ) emission, which is further confirmed by the very energetic radiation imaging telescope array system observations. the $ \ gamma $ - ray flux increased by more than an order in comparison to low activity state and the flare consists of multiple sub - structures having fast rise and slow decay profile. the flux enhancement is seen in all the wavebands though at a lesser extent compared to $ \ gamma $ - rays. during the flare, a considerable amount of the kinetic jet power gets converted to $ \ gamma $ - rays and the jet becomes radiatively efficient. a one zone leptonic emission model is used to reproduce the flare and we find increase in the bulk lorentz factor as a major cause of the outburst. from the observed fast variability, lack of vhe detection, and the curved $ \ gamma $ - ray spectrum, we conclude that the location of the emission region cannot be far out from the broad line region ( blr ) and contributions from both blr and torus photons are required to explain the observed $ \ gamma $ - ray spectrum.
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arxiv:1501.07363
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we present the result of calculations of the witten index for a supersymmetric lattice model on lattices of various type and size. because the model remains supersymmetric at finite lattice size, the witten index can be calculated using row - to - row transfer matrices and the calculations are similar to calculations of the partition function at negative activity - 1. the witten index provides a lower bound on the number of ground states. we find strong numerical evidence that the witten index grows exponentially with the number of sites of the lattice, implying that the model has extensive entropy in the ground state.
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arxiv:cond-mat/0509581
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in this paper, we initiate the study of the weighted paging problem with predictions. this continues the recent line of work in online algorithms with predictions, particularly that of lykouris and vassilvitski ( icml 2018 ) and rohatgi ( soda 2020 ) on unweighted paging with predictions. we show that unlike unweighted paging, neither a fixed lookahead nor knowledge of the next request for every page is sufficient information for an algorithm to overcome existing lower bounds in weighted paging. however, a combination of the two, which we call the strong per request prediction ( sprp ) model, suffices to give a 2 - competitive algorithm. we also explore the question of gracefully degrading algorithms with increasing prediction error, and give both upper and lower bounds for a set of natural measures of prediction error.
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arxiv:2006.09509
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the theoretical prediction that magnetic reconnection spontaneously drives turbulence has been supported by magnetohydrodynamic ( mhd ) and kinetic simulations. while reconnection with externally driven turbulence is accepted as an effective mechanism for particle acceleration, the acceleration during the reconnection with self - driven turbulence is studied for the first time in this work. by using high - resolution 3d mhd simulations of reconnection with self - generated turbulence, we inject test particles into the reconnection layer to study their acceleration process. we find that the energy gain of the particles takes place when they bounce back and forth between converging turbulent magnetic fields. the particles can be efficiently accelerated in self - driven turbulent reconnection with the energy increase by about 3 orders of magnitude in the range of the box size. the acceleration proceeds when the particle gyroradii become larger than the thickness of the reconnection layer. we find that the acceleration in the direction perpendicular to the local magnetic field dominates over that in the parallel direction. the energy spectrum of accelerated particles is time - dependent with a slope that evolves toward - 2. 5. our findings can have important implications for particle acceleration in high - energy astrophysical environments.
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arxiv:2308.07572
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anomalous symmetries are known to strongly constrain the possible ir behavior along any renormalization group ( rg ) flow. recently, the extension of the notion of symmetry in qft has provided new types of anomalies with a corresponding new class of constraints on rg flows. in this paper, we derive the constraints imposed on rg flows from anomalies that can only be activated in the presence of specific background fluxes even though they do not necessarily correspond to a symmetry. we show that such anomalies can only be matched by gapped theories that exhibit either spontaneous symmetry breaking or symmetry fractionalization. in addition, we exhibit previously unstudied examples of these flux background anomalies that arise in $ 4d $ qcd and $ 4d $ susy qcd.
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arxiv:2311.00093
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the paper is concerned with the existence and uniqueness of a strong solution to a two - dimensional backward stochastic navier - stokes equation with nonlinear forcing, driven by a brownian motion. we use the spectral approximation and the truncation and variational techniques. the methodology features an interactive analysis on basis of the regularity of the deterministic navier - stokes dynamics and the stochastic properties of the it \ ^ o - type diffusion processes.
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arxiv:1104.5567
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the stability of networks is greatly influenced by their degree distributions and in particular by their broadness. networks with broader degree distributions are usually more robust to random failures but less robust to localized attacks. to better understand the effect of the broadness of the degree distribution we study here two models where the broadness is controlled and compare their robustness against localized attacks ( la ) and random attacks ( ra ). we study analytically and by numerical simulations the cases where the degrees in the networks follow a bi - poisson distribution $ p ( k ) = \ alpha e ^ { - \ lambda _ 1 } \ frac { \ lambda _ 1 ^ k } { k! } + ( 1 - \ alpha ) e ^ { - \ lambda _ 2 } \ frac { \ lambda _ 2 ^ k } { k! }, \ alpha \ in [ 0, 1 ] $, and a gaussian distribution $ p ( k ) = a \ cdot exp { ( - \ frac { ( k - \ mu ) ^ 2 } { 2 \ sigma ^ 2 } ) } $ with a normalization constant $ a $ where $ k \ geq 0 $. in the bi - poisson distribution the broadness is controlled by the values of $ \ alpha $, $ \ lambda _ 1 $ and $ \ lambda _ 2 $, while in the gaussian distribution it is controlled by the standard deviation, $ \ sigma $. we find that only for $ \ alpha = 0 $ or $ \ alpha = 1 $, namely degrees obeying a pure poisson distribution, la and ra are the same but for all other cases networks are more vulnerable under la compared to ra. for gaussian distribution, with an average degree $ \ mu $ fixed, we find that when $ \ sigma ^ 2 $ is smaller than $ \ mu $ the network is more vulnerable against random attack. however, when $ \ sigma ^ 2 $ is larger than $ \ mu $ the network becomes more vulnerable against localized attack. similar qualitative results are also shown for interdependent networks.
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arxiv:1504.06900
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in cellular networks, resource allocation is performed in a centralized way, which brings huge computation complexity to the base station ( bs ) and high transmission overhead. this paper investigates the distributed resource allocation scheme for cellular networks to maximize the energy efficiency of the system in the uplink transmission, while guaranteeing the quality of service ( qos ) for cellular users. particularly, to cope the fast varying channels in wireless communication environment, we propose a robust federated reinforcement learning ( frl _ suc ) framework to enable local users to perform distributed resource allocation in items of transmit power and channel assignment by the guidance of the local neural network trained at each user. analysis and numerical results show that the proposed frl _ suc framework can lower the transmission overhead and offload the computation from the central server to the local users, while outperforming the conventional multi - agent reinforcement learning algorithm in terms of ee, and is more robust to channel variations.
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arxiv:2204.09602
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science saru, inc. ( japanese : 会 社 サイエンスsaru, hepburn : kabushiki - gaisha saiensu saru ), stylized as science saru, is a japanese animation studio headquartered in kichijoji, musashino, tokyo. established on february 4, 2013, by producer eunyoung choi and director masaaki yuasa, the studio has produced four feature films and five animated series, as well as co - productions, a compilation film, and episodes of series for other studios. science saru ' s first animation was the " food chain " episode of the american animated series adventure time ( 2014 ) ; its most recent projects are the animated feature film inu - oh ( 2021 ), two short films for the animated anthology project star wars : visions ( 2021 ), and the animated series the heike story ( 2021 ), yurei deco ( 2022 ), scott pilgrim takes off ( 2023 ), and dandadan ( 2024 ). the studio ' s work has received critical acclaim both within japan and internationally, winning awards from annecy, the japan academy film prize, the mainichi film awards, and the japan media arts festival. science saru utilizes a hybrid animation production method which combines hand - drawn animation and digital animation ( including flash animation ), a technique not previously used in japanese animation. the studio is currently led by eunyoung choi. = = name = = the studio ' s name science saru translates into english as " science monkey ". company co - founder masaaki yuasa frequently drew himself as a monkey in self - portraits, but wanted his company to be smarter than a monkey ; as a result, he added the word science in front of saru with the intent of having a company that possesses both instinct and intelligence. co - founder eunyoung choi further described the meaning behind the name : " we thought about a lot of possible names for the studio... science is like logic, business, numbers, plans, technology, and new tools. on the other hand, ' saru ' means monkey in japanese. as animators, we put in creativity, intuition, art, enjoying moments and being playful … a kind of ' monkeying around '. we want to keep these personalities in science saru. thus, we wanted to create a balance. ' science ' is in english, which highlights being international, and ' saru ' in japanese maintains traditional anime. " = = history = =
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https://en.wikipedia.org/wiki/Science_Saru
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recent experiments have shown that the striking structure formation in dewetting films of evaporating colloidal nanoparticle suspensions occurs in an ultrathin ` postcursor ' layer that is left behind by a mesoscopic dewetting front. various phase change and transport processes occur in the postcursor layer, that may lead to nanoparticle deposits in the form of labyrinthine, network or strongly branched ` finger ' structures. we develop a versatile dynamical density functional theory to model this system which captures all these structures and may be employed to investigate the influence of evaporation / condensation, nanoparticle transport and solute transport in a differentiated way. we highlight, in particular, the influence of the subtle interplay of decomposition in the layer and contact line motion on the observed particle - induced transverse instability of the dewetting front.
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arxiv:1001.2661
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recently there has been remarkable progress in the complex langevin method, which aims at solving the complex action problem by complexifying the dynamical variables in the original path integral. in particular, a new technique called the gauge cooling was introduced and the full qcd simulation at finite density has been made possible in the high temperature ( deconfined ) phase or with heavy quarks. here we provide a rigorous justification of the complex langevin method including the gauge cooling procedure. we first show that the gauge cooling can be formulated as an extra term in the complex langevin equation involving a gauge transformation parameter, which is chosen appropriately as a function of the configuration before cooling. the probability distribution of the complexified dynamical variables is modified by this extra term. however, this modification is shown not to affect the fokker - planck equation for the corresponding complex weight as far as observables are restricted to gauge invariant ones. thus we demonstrate explicitly that the gauge cooling can be used as a viable technique to satisfy the convergence conditions for the complex langevin method. we also discuss the " gauge cooling " in 0 - dimensional systems such as vector models or matrix models.
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arxiv:1508.02377
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in the forum section of the november, 1993 notices of the american mathematical society, john franks discussed the electronic journal of the future. since then, the new york journal of mathematics, the first electronic general mathematics journal, has begun publication. in this article, we explore the issues of electronic journal publishing in the context of this new project. we also discuss future developments.
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arxiv:math/9708203
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we study mott phases and superfluid - insulator ( si ) transitions of ultracold bosonic atoms in a two - dimensional square optical lattice at commensurate filling and in the presence of a synthetic periodic vector potential characterized by a strength $ p $ and a period $ l = qa $, where $ q $ is an integer and $ a $ is the lattice spacing. we show that the schr \ " odinger equation for the non - interacting bosons in the presence of such a periodic vector potential can be reduced to an one - dimensional harper - like equation which yields $ q $ energy bands. the lowest of these bands have either single or double minima whose position within the magnetic brillouin zone can be tuned by varying $ p $ for a given $ q $. using these energies and a strong - coupling expansion technique, we compute the phase diagram of these bosons in the presence of a deep optical lattice. we chart out the $ p $ and $ q $ dependence of the momentum distribution of the bosons in the mott phases near the si transitions and demonstrate that the bosons exhibit several re - entrant field - induced si transitions for any fixed period $ q $. we also predict that the superfluid density of the resultant superfluid state near such a si transition has a periodicity $ q $ ( $ q / 2 $ ) in real space for odd ( even ) $ q $ and suggest experiments to test our theory.
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arxiv:1005.4476
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