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Related papers: Upper bounds on the rate of quantum ergodicity

200 papers

The generic behavior of quantum systems has long been of theoretical and practical interest. Any quantum process is represented by a sequence of quantum channels. We consider general ergodic sequences of stochastic channels with arbitrary…

Quantum Physics · Physics 2022-07-08 Ramis Movassagh , Jeffrey Schenker

In this series, we investigate quantum ergodicity at small scales for linear hyperbolic maps of the torus ("cat maps"). In Part I of the series, we prove quantum ergodicity at various scales. Let $N=1/h$, in which $h$ is the Planck…

Mathematical Physics · Physics 2018-10-30 Xiaolong Han

Statistical mechanics is founded on the assumption that all accessible configurations of a system are equally likely. This requires dynamics that explore all states over time, known as ergodic dynamics. In isolated quantum systems, however,…

We discuss recent developments in the study of quantum wavefunctions and transport in classically ergodic systems. Surprisingly, short-time classical dynamics leaves permanent imprints on long-time and stationary quantum behavior, which are…

chao-dyn · Physics 2009-08-14 L. Kaplan

A simple argument shows that eigenstates of a classically ergodic system are individually ergodic on coarse-grained scales. This has implications for the quantization ambiguity in ergodic systems: the difference between alternative…

Quantum Physics · Physics 2009-08-14 L. Kaplan

We study the statistical and dynamical properties of the quantum triangle map, whose classical counterpart can exhibit ergodic and mixing dynamics, but is never chaotic. Numerical results show that ergodicity is a sufficient condition for…

Chaotic Dynamics · Physics 2022-05-19 Jiaozi Wang , Giuliano Benenti , Giulio Casati , Wen-ge Wang

We give an overview of the interplay between the behavior of high energy eigenfunctions of the Laplacian on a compact Riemannian manifold and the dynamical properties of the geodesic flow on that manifold. This includes the Quantum…

Analysis of PDEs · Mathematics 2024-01-02 Semyon Dyatlov

Does electron transfer (ET) kinetics within a single-electron trajectory description always coincide with the ensemble description? This fundamental question of ergodic behavior is scrutinized within a very basic semi-classical…

Mesoscale and Nanoscale Physics · Physics 2021-02-02 Igor Goychuk

The correlation between level velocities and eigenfunction intensities provides a new way of exploring phase space localization in quantized non-integrable systems. It can also serve as a measure of deviations from ergodicity due to quantum…

Chaotic Dynamics · Physics 2009-10-31 Arul Lakshminarayan , Nicholas R. Cerruti , Steven Tomsovic

We prove quantum ergodicity for certain orthonormal bases of $L^2(\mathbb{S}^2)$, consisting of joint eigenfunctions of the Laplacian on $\mathbb{S}^2$ and the discrete averaging operator over a finite set of rotations, generating a free…

Spectral Theory · Mathematics 2017-05-22 Shimon Brooks , Etienne Le Masson , Elon Lindenstrauss

Developing measures of quantum ergodicity and chaos stands as a foundational task in the study of quantum many-body systems. In this work, we propose metrics for these effects based on Hamiltonian learning that unify multiple advantages of…

Quantum Physics · Physics 2026-03-06 Nik O. Gjonbalaj , Christian Kokail , Susanne F. Yelin , Soonwon Choi

For a quantum-mechanical counting process we show ergodicity, under the condition that the underlying open quantum system approaches equilibrium in the time mean. This implies equality of time average and ensemble average for correlation…

Quantum Physics · Physics 2007-05-23 Burkhard Kuemmerer , Hans Maassen

Using the key properties of chaos, i.e. ergodicity and exponential instability, as a resource to control classical dynamics has a long and considerable history. However, in the context of controlling "chaotic" quantum unitary dynamics, the…

Quantum Physics · Physics 2025-12-17 Lukas Beringer , Mathias Steinhuber , Klaus Richter , Steven Tomsovic

In this thesis, we investigate quantum ergodicity for two classes of Hamiltonian systems satisfying intermediate dynamical hypotheses between the well understood extremes of ergodic flow and quantum completely integrable flow. These two…

Analysis of PDEs · Mathematics 2017-09-29 Sean Gomes

This undergraduate thesis is concerned with developing the tools of differential geometry and semiclassical analysis needed to understand the the quantum ergodicity theorem of Schnirelman (1974), Zelditch (1987), and Colin de Verdi\`ere…

Mathematical Physics · Physics 2014-10-14 Felix Wong

Resonance states in quantum chaotic scattering systems have a multifractal structure that depends on their decay rate. We show how classical dynamics describes this structure for all decay rates in the semiclassical limit. This result for…

Chaotic Dynamics · Physics 2025-01-20 Roland Ketzmerick , Florian Lorenz , Jan Robert Schmidt

Given a quantum Hamiltonian, we explain how the dynamical properties of the underlying classical system affect the behaviour of quantum eigenstates in the semi-classical limit. We study this problem via the notion of semiclassical measures.…

Mathematical Physics · Physics 2019-05-30 Gabriel Rivière

This paper is a physicist's review of the major conceptual issues concerning the problem of spectral universality in quantum systems. Here we present a unified, graph-based view of all archetypical models of such universality (billiards,…

Quantum Physics · Physics 2018-02-19 Wen Wei Ho , Djordje Radicevic

Exactly solvable models that exhibit quantum signatures of classical chaos are both rare as well as important - more so in view of the fact that the mechanisms for ergodic behavior and thermalization in isolated quantum systems and its…

Quantum Physics · Physics 2019-06-26 Shruti Dogra , Vaibhav Madhok , Arul Lakshminarayan

We propose a version of the Quantum Ergodicity theorem on large regular graphs of fixed valency. This is a property of delocalization of "most" eigenfunctions. We consider expander graphs with few short cycles (for instance random large…

Mathematical Physics · Physics 2015-11-03 Nalini Anantharaman , Etienne Le Masson