English

Quantum chaos in many-body systems of indistinguishable particles

Quantum Physics 2026-04-15 v1 High Energy Physics - Theory Chaotic Dynamics

Abstract

In quantum systems with a classical limit, advanced semiclassical methods provide the crucial link between phase-space structures, reflecting the distinction between chaotic, mixed or integrable classical dynamics, and the corresponding quantum properties. Well established techniques dealing with ergodic wave interference in the usual semiclassical limit 0\hbar \to 0, where the classical limit is given by Hamiltonian mechanics of particles, constitute a now standard part of the toolkit of theoretical physics. During the last years, these ideas have been extended into the field theoretical domain of systems composed of NN indistinguishable particles, aka quantum fields, displaying a different type of semiclassical limit eff=1/N0\hbar_{\rm eff}=1/N \to 0 and accounting for genuine many-body quantum interference. The foundational concept behind this idea of many-body interference, the many-body version of the van Vleck-Gutzwillers semiclassical propagator, is explained in detail. Based on this the corresponding semiclassical many-body theory is reviewed. It provides a unified framework for understanding a variety of quantum chaotic phenomena addressed, including random-matrix spectral correlations in many-body systems, the universal morphology of many-body eigenstates, interference effects kin to mesoscopic weak localization, and the key to the scrambling of many-body correlations characterized by out-of-time-order correlators.

Keywords

Cite

@article{arxiv.2604.12745,
  title  = {Quantum chaos in many-body systems of indistinguishable particles},
  author = {Juan-Diego Urbina and Klaus Richter},
  journal= {arXiv preprint arXiv:2604.12745},
  year   = {2026}
}

Comments

Chapter for the Quantum Chaos volume in 'Comprehensive Quantum Mechanics', to be published by Elsevier (Main editor: R. Mann; volume editors: S. Gnutzmann and K. {\.Z}yczkowski)