# Sound waves and vortices in a polarized relativistic fluid

## TL;DR

This paper extends the effective theory of ideal fluids to include non-zero polarization, analyzing how polarization influences sound waves, vortices, and the stability and causality of the fluid.

## Contribution

It introduces a new theoretical framework for polarized relativistic fluids and explores the effects of polarization on fluid dynamics and stability.

## Key findings

- Polarization modifies sound wave and vortex behavior.
- Presence of polarization impacts fluid stability.
- Causality considerations are affected by polarization.

## Abstract

We extend the effective theory approach to the ideal fluid limit where the polarization of the fluid is non-zero. After describing and motivating the equations of motion, we expand them around the hydrostatic limit, obtaining the sound wave and vortex degrees of freedom. We discuss how the presence of polarization affects the stability and causality of the ideal fluid limit.