Critical Opalescence around the QCD Critical Point and Second-order Relativistic Hydrodynamic Equations Compatible with Boltzmann Equation

摘要

The dynamical density fluctuations around QCD critical point (CP) areanalyzed using relativistic dissipative fluid dynamics, and we show that thesound mode around the QCD CP is strongly attenuated whereas the thermalfluctuation stands out there. We speculate that if possible suppression ordisappearance of a Mach cone, which seems to be created by the partonic jets atRHIC, is observed as the incident energy of the heavyion collisions isdecreased, it can be a signal of the existence of the QCD CP. We have presentedthe Israel-Stewart type fluid dynamic equations that are derived rigorously onthe basis of the (dynamical) renormalization group method in the second part ofthe talk, which we omit here because of a lack of space.