2021/09/13 by Gaoqing Cao, Lianyi He, Pengming Zhang · 3 citations
Physics and Astronomy · #Black Holes and Theoretical Physics #Particle physics theoretical and experimental studies #High-Energy Particle Collisions Research
paper · pdf · doi:10.1103/physrevd.104.054007
In this work, we self-consistently explore the possibility of charged pion superfluidity and cosmic trajectories in the early Universe under the framework of Polyakov-Nambu--Jona-Lasinio model. By taking the badly constrained lepton flavor asymmetries le and l_\ensuremathμ as free parameters, the upper boundaries of pion superfluidity phase are consistently found to be around the pseudocritical temperature at zero chemical potentials. So the results greatly support the choice of T=0.16 GeV as the upper boundary of pion superfluidity in the previous lattice QCD study. Take le+l_\ensuremathμ=\ensuremath-0.2 as an example, where we demonstrate the features of pion condensation and the associated cosmic trajectories with the evolution of the early Universe. While the trajectory of electric chemical potential reacts strongly at both the lower and upper boundaries of reentrant pion superfluidity, the trajectories of other chemical potentials only respond strongly at the upper boundary.