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Thermal modifications of mesons and energy-energy correlators from real-time simulations of a U(1) lattice gauge theory

João Barata1, David Frenklakh2,*, and Swagato Mukherjee2

  • *Contact author: dfrenklak@bnl.gov
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Phys. Rev. D 112, 114505 – Published 4 December, 2025

DOI: https://doi.org/10.1103/x3sn-vq11

Abstract

We investigate thermal properties of a U(1) lattice gauge theory in 1+1 dimensions through real-time simulations. We extract the spectral functions directly coupling to the pseudoscalar and scalar mesons, demonstrating the thermal modifications of these states with increasing temperatures. Introducing the notion of energy-flow operators, we quantify the temporal buildup of correlations in the energy flows across the lattice. We demonstrate that energy-energy correlators fail to factorize to products of energy flows, both in the vacuum and at nonzero temperature, indicating the presence of nontrivial correlations in the quantum states. Our results constitute a first real-time ab initio study of bound-state thermal broadening and finite temperature energy-flow correlations in a gauge theory, providing a benchmark for future studies of hadronic matter under extreme conditions.

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Phys. Rev. D 112, 114505– Published 4 December, 2025
  • Received 28 July 2025
  • Accepted 12 November 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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