2022/09/01 by Wei-jie Fu · 73 citations
paper · doi:10.1088/1572-9494/ac86be
published in Communications in Theoretical Physics 74(9), 097304 (IOP Publishing)
crossref created 2022/08/04 · crossref issued 2022/09/01 · crossref published 2022/09/01 · crossref published-print 2022/09/01 · crossref published-online 2022/09/12 · crossref deposited 2025/10/18 · crossref indexed 2026/08/07
Abstract In this paper, we present an overview on recent progress in studies of QCD at finite temperature and densities within the functional renormalization group (fRG) approach. The fRG is a nonperturbative continuum field approach, in which quantum, thermal and density fluctuations are integrated successively with the evolution of the renormalization group (RG) scale. The fRG results for the QCD phase structure and the location of the critical end point (CEP), the QCD equation of state (EoS), the magnetic EoS, baryon number fluctuations confronted with recent experimental measurements, various critical exponents, spectral functions in the critical region, the dynamical critical exponent, etc, are presented. Recent estimates of the location of the CEP from first-principle QCD calculations within fRG and Dyson–Schwinger equations, which pass through lattice benchmark tests at small baryon chemical potentials, converge in a rather small region at baryon chemical potentials of about 600 MeV. A region of inhomogeneous instability indicated by a negative wave function renormalization is found with μ B ≳ 420 MeV. It is found that the non-monotonic dependence of the kurtosis of the net-proton number distributions on the beam collision energy observed in experiments could arise from the increasingly sharp crossover in the regime of low collision energy.