Foundation of Hydrodynamics for Systems with Strong Interactions

TL;DR

This paper develops a quantum-based hydrodynamical framework for strongly interacting dense systems like nuclei and quark-gluon plasma, emphasizing the roles of quantum effects, mean-field interactions, and thermal fluctuations.

Contribution

It introduces a hydrodynamical formulation derived from quantum equations for many-body systems with strong interactions, highlighting different stress tensor contributions.

Findings

Quantum and mean-field stress tensors dominate at low and moderate temperatures.

Hydrodynamical equations incorporate quantum, mean-field, and thermal effects.

Framework applicable to dense, strongly interacting systems like nuclear matter.

Abstract

For a dense and strongly interacting system, such as a nucleus or a strongly-coupled quark-gluon plasma, the foundation of hydrodynamics can be better found in the quantum description of constituents moving in the strong mean fields generated by all other particles. Using the result that the Schroedinger equation and the Klein-Gordon equation can be written in hydrodynamical forms, we find that the probability currents of the many-body system in the mean-field description obey a hydrodynamical equation with stress tensors arising from many contributions: quantum effects, mean-field interactions, and thermal fluctuations. The influence of various contributions to the hydrodynamical motion is expected to vary with the temperature, as the quantum and mean-field stress tensors playing more important roles at low and moderate temperatures.