Speaker
Kenji Morita
(Kyoto University)
Description
The speed of sound $c_s^2 = (\partial P /\partial \varepsilon)_{\text{adiabatic}}$ plays an important role in the hydrodynamic evolution of the hot and dense matter.
We calculate the behavior of $c_s^2$ in a chiral quark-meson model at finite temperature and baryon density and discuss possible consequences of the chiral phase transition which belongs to 3d $O(4)$ universality class. By comparing the results from the no-sea mean-field approximation, the mean field approximation with fermion vacuum polarization and the case where fluctuations are fully incorporated via functional renormalization group (FRG) approach, we show that the chiral phase transition does not produce a minimum in $c_s^2$.
Our result may imply that such minimum of $c_s^2$ observed in lattice QCD at finite temperature is entirely attributed to the deconfinement phenomenon.
Primary author
Kenji Morita
(Kyoto University)
Co-author
Krzysztof Redlich
(University of Wroclaw)
