Hydro+: hydrodynamics with parametric slowing down and fluctuations near the critical point

Understand

The search for the QCD critical point in heavy-ion collision experiments requires dynamical simulations of the bulk evolution of QCD matter as well as of fluctuations.

• We consider two essential ingredients of such a simulation: a generic extension of hydrodynamics by a_parametrically_ slow mode or modes ("Hydro+") and a description of fluctuations out of equilibrium.
• By combining the two ingredients we are able to describe the bulk evolution and the fluctutations within the same framework.
• Critical slowing down means that equilibration of fluctuations could be as slow as hydrodynamic evolution and thus fluctuations could significantly deviate from equilibrium near the critical point.