Speaker
Prof.
Mikhail Stephanov
(UIC)
Description
The search for the QCD critical point in heavy-ion collision
experiments requires dynamical modeling of the bulk evolution of the
QCD matter as well as of the fluctuations near the critical
point. Critical slowing down means that fluctuations are significantly
deviating from equilibrium near the critical point. We generalize
hydrodynamics to quasi-equilibrium conditions where the state of the
system is characterized by the off-equilibrium magnitude of
fluctuations in addition to the usual hydrodynamic variables --
conserved densities. We find that the key ingredient of the formalism
-– the extended entropy taking into account the off-equilibrium
fluctuations -- is remarkably similar to the 2PI action in quantum
field theory. We use the new formalism to demonstrate the major
effects of critical fluctuations on the bulk evolution: the strong
frequency dependence of the anomalously large bulk viscosity as well
as the stiffening of the equation of state with increasing frequency
or wave-number.
Primary authors
Prof.
Mikhail Stephanov
(UIC)
Dr
Yi Yin
(MIT)
