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Thermalization from quantum entanglement: Jet simulations in the massive Schwinger model

Adrien Florio1,2,*, David Frenklakh2,†, Sebastian Grieninger3,‡, Dmitri E. Kharzeev3,4,§, Andrea Palermo3,∥, and Shuzhe Shi5,6,¶

  • *Contact author: aflorio@physik.uni-bielefeld.de
  • †Contact author: dfrenklak@bnl.gov
  • ‡Contact author: sebastian.grieninger@stonybrook.edu
  • §Contact author: dmitri.kharzeev@stonybrook.edu
  • ∥Contact author: andrea.palermo@stonybrook.edu
  • Contact author: shuzhe-shi@tsinghua.edu.cn
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Phys. Rev. D 112, 094502 – Published 7 November, 2025

DOI: https://doi.org/10.1103/sgrx-jpp9

Abstract

We investigate the emergence of thermalization in a quantum-field-theoretic model mimicking the production of jets in QCD: the massive lattice Schwinger model coupled to external sources. Specifically, we compute the expectation values of local operators as functions of time and compare them to their thermal counterparts, quantify the overlap between the evolving density matrix and the thermal one, and compare the dynamics of the energy-momentum tensor to predictions from relativistic hydrodynamics. Through these studies, we find that the system approaches thermalization at late times and elucidate the mechanisms by which quantum entanglement drives thermalization in closed field-theoretic systems. Our results show how thermodynamic behavior emerges in real time from unitary quantum dynamics.

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Phys. Rev. D 112, 094502– Published 7 November, 2025
  • Received 9 July 2025
  • Accepted 6 October 2025
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