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QCD vacuum energy and its implication for quark nugget stability

Yang Bai1,2 and Ting-Kuo Chen1

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Phys. Rev. D 113, 114024 – Published 15 June, 2026

DOI: https://doi.org/10.1103/sp4n-twcz

Abstract

In this work, we employ both theoretical and data-driven methods to derive the QCD vacuum energy, utilizing the GMOR relation, the low-energy theorem, and the equation of state from lattice QCD. The QCD vacuum energy is determined to be between around (163  MeV)4 and (190  MeV)4. With the assumptions of complete deconfinement, vanishing gluon condensate, full chiral-symmetry restoration, and the validity of perturbative QCD at baryon chemical potentials of order of the proton mass, a very specific kind of quark nugget is found to be less stable than ordinary nuclei.

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Phys. Rev. D 113, 114024– Published 15 June, 2026
  • Received 28 January 2026
  • Accepted 26 May 2026
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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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