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Quenching through the QCD chiral phase transition

Adrien Florio1,2,*, Eduardo Grossi3,†, Aleksas Mazeliauskas4,‡, Alexander Soloviev5,§, and Derek Teaney6,∥

  • *Contact author: aflorio@physik.uni-bielefeld.de
  • †Contact author: eduardo.grossi@unifi.it
  • ‡Contact author: a.mazeliauskas@thphys.uni-heidelberg.de
  • §Contact author: alexander.soloviev@fmf.uni-lj.si
  • ∥Contact author: derek.teaney@stonybrook.edu
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Phys. Rev. D 112, 114019 – Published 12 December, 2025

DOI: https://doi.org/10.1103/plfm-z5xx

Abstract

We present a detailed numerical and analytical study of the out-of-equilibrium dynamics of Model G, the dynamical universality class relevant to the chiral phase transition. We perform numerical 3D stochastic (Langevin) simulations of the O(4) critical point for large lattices in the chiral limit. We quench the system from the high-temperature unbroken phase to the broken phase and study the nonequilibrium dynamics of pion fields. Strikingly, the nonequilibrium evolution of the two-point functions exhibits a regime of growth, a parametrically large enhancement, and a subsequent slow relaxation to equilibrium. We analyze our numerical results using dynamic critical scaling and mean-field theory. The growth of the two-point functions is determined by the nonlinear dynamics of an ideal non-Abelian superfluid, which is a limit of Model G that reflects the broken chiral symmetry. We also relate the nonequilibrium two-point functions to a long-lived parametric enhancement of soft pion yields relative to thermal equilibrium following a quench.

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See Also

Supercooled Goldstone Bosons at the QCD Chiral Phase Transition

Adrien Florio, Eduardo Grossi, Aleksas Mazeliauskas, Alexander Soloviev, and Derek Teaney
Phys. Rev. Lett. 135, 242303 (2025)

Article Text

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Phys. Rev. D 112, 114019– Published 12 December, 2025
  • Received 1 July 2025
  • Accepted 11 November 2025
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