2019 journal article

Stochastic hydrodynamics and long time tails of an expanding conformal charged fluid

Phys.Rev.C, 99(5), 054902.

co-author countries: United States of America 🇺🇸
Source: ORCID
Added: August 15, 2019

We investigate the impact of hydrodynamic fluctuations on correlation functions in a scale invariant fluid with a conserved $\text{U}(1)$ charge. The kinetic equations for the two-point functions of pressure, momentum, and heat energy densities are derived within the framework of stochastic hydrodynamics. The leading nonanalytic contributions to the energy-momentum tensor as well as the $\text{U}(1)$ current are determined from the solutions to these kinetic equations. In the case of a static homogeneous background we show that the long time tails obtained from hydrokinetic equations reproduce the one-loop results derived from statistical field theory. We use these results to establish bounds on transport coefficients. We generalize the stochastic equation to a background flow undergoing Bjorken expansion. We compute the leading fractional power $\mathcal{O}({(\ensuremath{\tau}T)}^{\ensuremath{-}3/2})$ correction to the $\text{U}(1)$ current and compare with the first-order gradient term.