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Finite density signatures of confining and chiral dynamics in QCD thermodynamics and fluctuations of conserved charges

Yi Lu1,*, Fei Gao2,†, Yu-xin Liu1,3,4,‡, and Jan M. Pawlowski5,6,§

  • *Contact author: qwertylou@pku.edu.cn
  • †Contact author: fei.gao@bit.edu.cn
  • ‡Contact author: yxliu@pku.edu.cn
  • §Contact author: J.Pawlowski@thphys.uni-heidelberg.de
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Phys. Rev. D 113, 054019 – Published 12 March, 2026

DOI: https://doi.org/10.1103/s1kg-cl9p

Abstract

We evaluate thermodynamic observables such as pressure, baryon number, entropy and energy density, as well as the second and fourth order baryon number cumulants in the phase structure of QCD. The intertwined confinement and chiral dynamics is resolved within functional QCD, aiming for quantitative accuracy at larger densities. Specifically it is shown that the self-consistent resolution of the confining gluonic background is crucial in particular for even the qualitative properties of the cumulants. Our results are in quantitative agreement with lattice and functional QCD benchmarks at vanishing and small chemical potentials. Moreover, they offer novel insights into the dynamics at larger chemical potentials including the regime of the critical end point. A welcome by-product of this analysis is the computation of the Polyakov loop potential in finite density QCD, which, alongside the aforementioned observables, can be used as input and benchmark for effective theory computations at finite density.

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Phys. Rev. D 113, 054019– Published 12 March, 2026
  • Received 22 April 2025
  • Accepted 23 February 2026
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