Hydrodynamics of nuclear matter in the chiral limit

TL;DR

This paper develops a hydrodynamic framework for nuclear matter in the chiral limit, incorporating fluid dynamics and pion behavior, revealing pion velocity vanishes at the phase transition for Nf=2.

Contribution

It constructs a comprehensive hydrodynamic model including low-energy degrees of freedom like pions and baryonic charges using the Poisson bracket method.

Findings

Pion velocity vanishes at the second order phase transition for Nf=2.

Hydrodynamic equations include relativistic fluid dynamics and pion propagation.

The model describes both fluid and pionic degrees of freedom in nuclear matter.

Abstract

Using the Poisson bracket method, we construct the hydrodynamics of nuclear matter in the chiral limit, which describes the dynamics of all low-energy degrees of freedom, including the fluid-dynamical and pionic ones. The hydrodynamic equations contain, beside five Euler equations of relativistic fluid dynamics, Nf^2-1 second order equations describing propagating pions and Nf^2-1 first order equations describing the advection of the baryonic vector isospin charges. We present hydrodynamic arguments showing that the pion velocity vanishes at the second order phase transition at Nf=2.