Approaching Stable Quark Matter
arXiv:2410.19678 · doi:10.1140/epjc/s10052-026-15340-9
Abstract
The determination of whether the ground state of baryon matter in Quantum Chromodynamics (QCD) is the ordinary nucleus or a quark matter state remains a long-standing question in physics. A critical parameter in this investigation is the bag parameter , which quantifies the QCD vacuum energy and can be computed using nonperturbative methods such as Lattice QCD (LQCD). By combining the equation of state derived from perturbative QCD (pQCD) with the bag parameter to fit the LQCD-simulated data for isospin-dense matter, we address the stability of quark matter within the LQCD+pQCD framework. Our findings suggest that the current data imposes an upper bound on MeV, approaching a conclusive statement on quark matter stability. Given the lower bound on from the quark condensate contribution to the vacuum energy, the stable 2-flavor quark matter remains possible, whereas the stable 2+1-flavor quark matter is excluded, assuming complete deconfinement and chiral-symmetry restoration and the reliability of pQCD at baryon chemical potentials around the proton mass. Additionally, we derive more general thermodynamic bounds on the quark matter energy-per-baryon and , which, while weaker, provide complementary insights.
31 pages, 14 figures, matches the published version
References in corpus (19)
- The equation of state in (2+1)-flavor QCD
- The QCD Equation of State with almost Physical Quark Masses
- Equation of state and QCD transition at finite temperature
- Cold Quark Matter
- Gluon condensate in charmonium sum rules with 3-loop corrections
- How perturbative QCD constrains the Equation of State at Neutron-Star densities
- Quark matter may not be strange
- Direct determination of the strange and light quark condensates from full lattice QCD
- Matching Excluded Volume Hadron Resonance Gas Models and Perturbative QCD to Lattice Calculations
- QCD equation of state with 2+1 flavors of improved staggered quarks
- Equation of State in 2+1 Flavor QCD at High Temperatures
- QCD Parameters Correlations from Heavy Quarkonia
- SU(2) chiral perturbation theory low-energy constants from 2+1 flavor staggered lattice simulations
- Equation of State of Cold Quark Matter to
- Stability windows for proto-quark stars
- Lattice QCD at finite temperature : present status
- QCD inequalities for the nucleon mass and the free energy of baryonic matter
- Enhanced contribution of the pairing gap to the QCD equation of state at large isospin chemical potential
- Correlations between the strange quark condensate, strange quark mass, and kaon PCAC relation