Latest developments in anisotropic hydrodynamics

TL;DR

This paper reviews recent advances in anisotropic hydrodynamics, highlighting its consistency with second order viscous hydrodynamics and exact Boltzmann solutions, especially in higher-dimensional cases.

Contribution

It introduces a new set of equations for anisotropic hydrodynamics that are valid in (3+1) dimensions and simplify the description of pressure anisotropies.

Findings

Consistency with second order viscous hydrodynamics in multiple dimensions

Agreement with exact Boltzmann solutions in simplified cases

New equations that eliminate the need for next-to-leading order corrections

Abstract

We discuss the leading order of anisotropic hydrodynamics expansion. It has already been shown that in the (0+1) and (1+1)-dimensional cases it is consistent with the second order viscous hydrodynamics, and it provides a striking agreement with the exact solutions of the Boltzmann equation. Quite recently, a new set of equations has been proposed for the leading order of anisotropic hydrodynamics, which is consistent with the second order viscous hydrodynamics in the most general (3+1)-dimensional case, and does not require a next-to-leading treatment for describing pressure anisotropies in the transverse plane.