Relativistic hydrodynamics from quantum field theory on the basis of the generalized Gibbs ensemble method

TL;DR

This paper derives relativistic hydrodynamics from quantum field theory using the generalized Gibbs ensemble, providing a microscopic foundation and explicit equations for both nondissipative and dissipative dynamics.

Contribution

It introduces a method to derive relativistic hydrodynamics directly from quantum field theory without relying on frame choices, using the generalized Gibbs ensemble approach.

Findings

Microscopic derivation of nondissipative hydrodynamics

First-order dissipative hydrodynamic equations derived

Framework applicable without frame dependence

Abstract

We derive relativistic hydrodynamics from quantum field theories by assuming that the density operator is given by a local Gibbs distribution at initial time. We decompose the energy-momentum tensor and particle current into nondissipative and dissipative parts, and analyze their time evolution in detail. Performing the path-integral formulation of the local Gibbs distribution, we microscopically derive the generating functional for the nondissipative hydrodynamics.We also construct a basis to study dissipative corrections. In particular, we derive the first-order dissipative hydrodynamic equations without a choice of frame such as the Landau-Lifshitz or Eckart frame.