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Emergent Nonthermal Fluid from Jets in the Massive Schwinger Model Using Tensor Networks

Romuald A. Janik1,*, Maciej A. Nowak1,†, Marek M. Rams1,‡, and Ismail Zahed2,§

  • 1Institute of Theoretical Physics and Mark Kac Center for Complex Systems Research, Jagiellonian University, 30-348 Kraków, Poland
  • 2Center for Nuclear Theory, Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794–3800, USA

  • *Contact author: romuald.janik@gmail.com
  • †Contact author: maciej.a.nowak@uj.edu.pl
  • ‡Contact author: marek.rams@uj.edu.pl
  • §Contact author: ismail.zahed@stonybrook.edu
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Phys. Rev. Lett. 135, 211903 – Published 20 November, 2025

DOI: https://doi.org/10.1103/gvr2-gqys

Abstract

We analyze the correlation between the energy, momentum, and spatial entanglement produced by two luminal jets in the massive Schwinger model. Using tensor network methods, we show that for m/g>1/π, in the vicinity of the strong- to weak-coupling transition, a nearly perfect and chargeless effective fluid behavior appears around the midrapidity region with a universal energy-pressure relationship. The evolution of energy and pressure is strongly correlated with the rise of the spatial entanglement entropy, indicating a key role of quantum dynamics. Some of these observations may be used to analyze high multiplicity jet fragmentation events, energy-energy and energy-charge correlators at current collider energies.

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Phys. Rev. Lett. 135, 211903– Published 20 November, 2025
  • Received 4 March 2025
  • Revised 24 July 2025
  • Accepted 3 November 2025
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