arXiv: Statistical Mechanics最新文献_第7页

Duality in quantum transport models 量子输运模型中的对偶性

arXiv: Statistical Mechanics Pub Date : 2020-08-08 DOI: 10.21468/SciPostPhys.10.6.135

Rouven Frassek, C. Giardinà, J. Kurchan

引用次数: 6

Modification of quantum many-body relaxation by perturbations exhibiting a banded matrix structure 显示带状矩阵结构的扰动对量子多体弛豫的修正

arXiv: Statistical Mechanics Pub Date : 2020-08-06 DOI: 10.1103/PhysRevResearch.2.033210

Lennart Dabelow, P. Vorndamme, P. Reimann

引用次数: 4

Covariant formulation of nonlinear Langevin theory with multiplicative Gaussian white noises 具有乘性高斯白噪声的非线性朗之万理论的协变公式

arXiv: Statistical Mechanics Pub Date : 2020-07-31 DOI: 10.1103/physrevresearch.2.033381

Mingnan Ding, Z. Tu, Xiangjun Xing

引用次数: 10

Exactly solvable model of calorimetric measurements 量热测量的精确可解模型

arXiv: Statistical Mechanics Pub Date : 2020-07-31 DOI: 10.1103/physrevb.102.245401

Brecht Donvil, Paolo Muratore-Ginanneschi, D. Golubev

引用次数: 9

A systematic $1/c$-expansion of form factor sums for dynamical correlations in the Lieb-Liniger model 利布-利尼格模型中动态关联形式因子和的系统$1/c$展开

arXiv: Statistical Mechanics Pub Date : 2020-07-30 DOI: 10.21468/SCIPOSTPHYS.9.6.082

Etienne Granet, F. Essler

{"title":"A systematic $1/c$-expansion of form factor sums for dynamical correlations in the Lieb-Liniger model","authors":"Etienne Granet, F. Essler","doi":"10.21468/SCIPOSTPHYS.9.6.082","DOIUrl":"https://doi.org/10.21468/SCIPOSTPHYS.9.6.082","url":null,"abstract":"We introduce a framework for calculating dynamical correlations in the Lieb-Liniger model in arbitrary energy eigenstates and for all space and time, that combines a Lehmann representation with a $1/c$ expansion. The $n^{rm th}$ term of the expansion is of order $1/c^n$ and takes into account all $lfloor tfrac{n}{2}rfloor+1$ particle-hole excitations over the averaging eigenstate. Importantly, in contrast to a 'bare' $1/c$ expansion it is uniform in space and time. The framework is based on a method for taking the thermodynamic limit of sums of form factors that exhibit non integrable singularities. We expect our framework to be applicable to any local operator. \u0000We determine the first three terms of this expansion and obtain an explicit expression for the density-density dynamical correlations and the dynamical structure factor at order $1/c^2$. We apply these to finite-temperature equilibrium states and non-equilibrium steady states after quantum quenches. We recover predictions of (nonlinear) Luttinger liquid theory and generalized hydrodynamics in the appropriate limits, and are able to compute sub-leading corrections to these.","PeriodicalId":8473,"journal":{"name":"arXiv: Statistical Mechanics","volume":"80 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81235024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 27

Hydrodynamics in lattice models with continuous non-Abelian symmetries 连续非阿贝尔对称格模型中的流体力学

arXiv: Statistical Mechanics Pub Date : 2020-07-27 DOI: 10.21468/SCIPOSTPHYS.10.1.015

Paolo Glorioso, Luca V. Delacr'etaz, Xiao Chen, R. Nandkishore, A. Lucas

{"title":"Hydrodynamics in lattice models with continuous non-Abelian symmetries","authors":"Paolo Glorioso, Luca V. Delacr'etaz, Xiao Chen, R. Nandkishore, A. Lucas","doi":"10.21468/SCIPOSTPHYS.10.1.015","DOIUrl":"https://doi.org/10.21468/SCIPOSTPHYS.10.1.015","url":null,"abstract":"We develop a systematic effective field theory of hydrodynamics for many-body systems on the lattice with global continuous non-Abelian symmetries. Models with continuous non-Abelian symmetries are ubiquitous in physics, arising in diverse settings ranging from hot nuclear matter to cold atomic gases and quantum spin chains. In every dimension and for every flavor symmetry group, the low energy theory is a set of coupled noisy diffusion equations. Independence of the physics on the choice of canonical or microcanonical ensemble is manifest in our hydrodynamic expansion, even though the ensemble choice causes an apparent shift in quasinormal mode spectra. We use our formalism to explain why flavor symmetry is qualitatively different from hydrodynamics with other non-Abelian conservation laws, including angular momentum and charge multipoles. As a significant application of our framework, we study spin and energy diffusion in classical one-dimensional SU(2)-invariant spin chains, including the Heisenberg model along with multiple generalizations. We argue based on both numerical simulations and our effective field theory framework that non-integrable spin chains on a lattice exhibit conventional spin diffusion, in contrast to some recent predictions that diffusion constants grow logarithmically at late times. We show that the apparent enhancement of diffusion is due to slow equilibration caused by (non-Abelian) hydrodynamic fluctuations.","PeriodicalId":8473,"journal":{"name":"arXiv: Statistical Mechanics","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76695429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 31

Escape problem for active particles confined to a disk 被限制在圆盘上的活性粒子的逃逸问题

arXiv: Statistical Mechanics Pub Date : 2020-07-17 DOI: 10.1103/physrevresearch.2.043314

K. S. Olsen, L. Angheluta, E. Flekkøy

引用次数: 7

Bistabilities and domain walls in weakly open quantum systems 弱开放量子系统的双稳定性和畴壁

arXiv: Statistical Mechanics Pub Date : 2020-07-16 DOI: 10.21468/scipostphys.9.4.057

F. Lange, A. Rosch

{"title":"Bistabilities and domain walls in weakly open quantum systems","authors":"F. Lange, A. Rosch","doi":"10.21468/scipostphys.9.4.057","DOIUrl":"https://doi.org/10.21468/scipostphys.9.4.057","url":null,"abstract":"Weakly pumped systems with approximate conservation laws can be efficiently described by a generalized Gibbs ensemble if the steady state of the system is unique. However, such a description can fail if there are multiple steady state solutions, for example, a bistability. In this case domains and domain walls may form. In one-dimensional (1D) systems any type of noise (thermal or non-thermal) will in general lead to a proliferation of such domains. We study this physics in a 1D spin chain with two approximate conservation laws, energy and the $z$-component of the total magnetization. A bistability in the magnetization is induced by the coupling to suitably chosen Lindblad operators. We analyze the theory for a weak coupling strength $epsilon$ to the non-equilibrium bath. In this limit, we argue that one can use hydrodynamic approximations which describe the system locally in terms of space- and time-dependent Lagrange parameters. Here noise terms enforce the creation of domains, where the typical width of a domain wall goes as $sim 1/sqrt{epsilon}$ while the density of domain walls is exponentially small in $1/sqrt{epsilon}$. This is shown by numerical simulations of a simplified hydrodynamic equation in the presence of noise.","PeriodicalId":8473,"journal":{"name":"arXiv: Statistical Mechanics","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84566523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Lévy Flights in Steep Potential Wells: Langevin Modeling Versus Direct Response to Energy Landscapes 陡势井中的lsamvy飞行:Langevin模型与对能源景观的直接响应

arXiv: Statistical Mechanics Pub Date : 2020-07-07 DOI: 10.5506/aphyspolb.51.1965

P. Garbaczewski, M. Żaba

{"title":"Lévy Flights in Steep Potential Wells: Langevin Modeling Versus Direct Response to Energy Landscapes","authors":"P. Garbaczewski, M. Żaba","doi":"10.5506/aphyspolb.51.1965","DOIUrl":"https://doi.org/10.5506/aphyspolb.51.1965","url":null,"abstract":"We investigate the non-Langevin relative of the Levy-driven Langevin random system, under an assumption that both systems share a common (asymptotic, stationary, steady-state) target pdf. The relaxation to equilibrium in the fractional Langevin-Fokker-Planck scenario results from an impact of confining conservative force fields on the random motion. A non-Langevin alternative has a built-in direct response of jump intensities to energy (potential) landscapes in which the process takes place. We revisit the problem of Levy flights in superharmonic potential wells, with a focus on the extremally steep well regime, and address the issue of its (spectral) \"closeness\" to the Levy jump-type process confined in a finite enclosure with impenetrable (in particular reflecting) boundaries. The pertinent random system \"in a box/interval\" is expected to have a fractional Laplacian with suitable boundary conditions as a legitimate motion generator. The problem is, that in contrast to amply studied Dirichlet boundary problems, a concept of reflecting boundary conditions and the path-wise implementation of the pertinent random process in the vicinity of (or sharply at) reflecting boundaries are not unequivocally settled for Levy processes. This ambiguity extends to fractional motion generators, for which nonlocal analogs of Neumann conditions are not associated with path-wise reflection scenarios at the boundary, respecting the impenetrability assumption.","PeriodicalId":8473,"journal":{"name":"arXiv: Statistical Mechanics","volume":"35 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76581671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Light and heavy particles on a fluctuating surface: Bunchwise balance, irreducible sequences, and local density-height correlations 波动表面上的轻粒子和重粒子:束状平衡、不可约序列和局部密度高度相关性

arXiv: Statistical Mechanics Pub Date : 2020-07-06 DOI: 10.1103/physrevresearch.2.043279

S. Mahapatra, K. Ramola, M. Barma

{"title":"Light and heavy particles on a fluctuating surface: Bunchwise balance, irreducible sequences, and local density-height correlations","authors":"S. Mahapatra, K. Ramola, M. Barma","doi":"10.1103/physrevresearch.2.043279","DOIUrl":"https://doi.org/10.1103/physrevresearch.2.043279","url":null,"abstract":"We study the early time and coarsening dynamics in a system consisting of two species of particles ($light$ and $heavy$) coupled to a fluctuating surface (described by tilt fields). The dynamics of particles and tilts are coupled through local update rules, and lead to different ordered and disordered steady state phases depending on the microscopic rates. We introduce a generalised balance mechanism in non-equilibrium systems, namely $bunchwise~balance$, in which incoming and outgoing transition currents are balanced between groups of configurations. This allows us to exactly determine the steady state in a subspace of the phase diagram of this model. We introduce the concept of $irreducible~sequences$ of interfaces and bends in this model. These sequences are non-local, and we show that they provide a coarsening length scale in the ordered phases at late times. Finally, we propose a $local$ correlation function ($mathcal{S}$) that has a direct relation to the number of irreducible sequences, and is able to distinguish between several phases of this system through its coarsening properties. Starting from a totally disordered initial configuration, $mathcal{S}$ displays an initial linear rise and a broad maximum. As the system evolves towards the ordered steady states, $mathcal{S}$ further exhibits power law decays at late times that encode coarsening properties of the approach to the ordered phases. Focusing on early time dynamics, we posit coupled mean-field evolution equations governing the particles and tilts, which at short times are well approximated by a set of linearized equations, which we solve analytically. Beyond a timescale set by an ultraviolet (lattice) cutoff and preceding the onset of coarsening, our linearized theory predicts the existence of an intermediate diffusive (power-law) stretch, which we also find in simulations of the ordered regime of the system.","PeriodicalId":8473,"journal":{"name":"arXiv: Statistical Mechanics","volume":"34 10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77915762","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3