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Supercooled Goldstone Bosons at 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. Lett. 135, 242303 – Published 12 December, 2025

DOI: https://doi.org/10.1103/wyn4-ncdc

Abstract

We discuss a universal nonequilibrium enhancement of long-wavelength Goldstone bosons induced by quenches to the broken phase in Model G—the dynamical universality class of an O(4) antiferromagnet and the chiral phase transition in QCD. Scaling arguments for the coarsening dynamics describing the formation of the chiral condensate predict a parametric enhancement in the infrared spectra of Goldstone bosons, a prediction confirmed by stochastic simulations of the transition. The details of the enhancement are determined by the nonlinear dynamics of a superfluid effective theory, which is a limit of Model G reflecting the broken O(4) symmetry. Our results translate to a parametric enhancement of low-momentum pions in heavy-ion collisions at the LHC, which are underpredicted in current hydrodynamic models without critical dynamics.

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Physics Subject Headings (PhySH)

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Quenching through the QCD chiral phase transition

Adrien Florio, Eduardo Grossi, Aleksas Mazeliauskas, Alexander Soloviev, and Derek Teaney
Phys. Rev. D 112, 114019 (2025)

Article Text

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Phys. Rev. Lett. 135, 242303– Published 12 December, 2025
  • Received 1 July 2025
  • Revised 10 October 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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