Evidence for a Continuous Hadron--Quark Transition in Cold Dense Matter
Abstract
Statistical evidence for a continuous hadron-quark transition is found in this work. Confronting microscopic descriptions connecting the Parity Doublet Model and the Nambu--Jona-Lasinio model with observationally constrained non-parametric equations of state, Bayesian model comparison decisively favors a boundary-free crossover over the conventional first-order Maxwell construction (Δln𝒵 ∼ +7.20) and fixed-boundary crossover ($Δ\ln\mathcal{Z} \sim +5.16 $). The preferred crossover decouples the intermediate stiffening from the intrinsic stiffness of each phase, allowing both sectors to exhibit physical self-consistency. The chiral-invariant nucleon mass is large, M0 = 834+28−92 MeV, as expected for a substantial baryon mass surviving chiral restoration. While the quark sector accommodates a small pairing gap ΔCFL = 88+83−59 MeV consistent with perturbative QCD limits, avoiding the excessively large gaps ΔCFL ≳ 200 MeV required by the other constructions. These results demonstrate that a realistic unified description represents a continuous transition deviating substantially from isolated effective models of hadrons and quarks. Exploring genuine phase boundaries is therefore necessary through the emergence of spinodal instabilities within unified frameworks.
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BibTeX
@misc{huang2026evidence,
title = {{Evidence for a Continuous Hadron--Quark Transition in Cold Dense Matter}},
author = {Yong-Jia Huang and Bikai Gao},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.22450},
eprint = {2609.22450},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.22450},
note = {CC0},
}
RIS
TY - UNPB
TI - Evidence for a Continuous Hadron--Quark Transition in Cold Dense Matter
AU - Yong-Jia Huang
AU - Bikai Gao
PY - 2026
DA - 2026/09/18
PB - arXiv
DO - 10.48550/arxiv.2609.22450
UR - https://arxiv.org/abs/2609.22450
AB - Statistical evidence for a continuous hadron-quark transition is found in this work. Confronting microscopic descriptions connecting the Parity Doublet Model and the Nambu--Jona-Lasinio model with observationally constrained non-parametric equations of state, Bayesian model comparison decisively favors a boundary-free crossover over the conventional first-order Maxwell construction (Δln𝒵 ∼ +7.20) and fixed-boundary crossover ($Δ\ln\mathcal{Z} \sim +5.16 $). The preferred crossover decouples the intermediate stiffening from the intrinsic stiffness of each phase, allowing both sectors to exhibit physical self-consistency. The chiral-invariant nucleon mass is large, M_0 = 834^+28_−92 MeV, as expected for a substantial baryon mass surviving chiral restoration. While the quark sector accommodates a small pairing gap Δ_CFL = 88^+83_−59 MeV consistent with perturbative QCD limits, avoiding the excessively large gaps Δ_CFL ≳ 200 MeV required by the other constructions. These results demonstrate that a realistic unified description represents a continuous transition deviating substantially from isolated effective models of hadrons and quarks. Exploring genuine phase boundaries is therefore necessary through the emergence of spinodal instabilities within unified frameworks.
ER -