Carrollian fluids and spontaneous breaking of boost symmetry

TL;DR

This paper explores the unique role of boost symmetry breaking in Carrollian fluids, revealing how their thermodynamic and dissipative properties differ from relativistic fluids and deriving their equilibrium currents from first principles.

Contribution

It demonstrates that in Carrollian field theories, the boost Goldstone field is fundamental, enabling a first-principles derivation of fluid properties and connecting to the relativistic limit.

Findings

Boost Goldstone field is central in Carrollian fluids.

Derived equilibrium currents and dissipative effects from first principles.

Established the connection between Carrollian fluids and the zero-speed-of-light limit.

Abstract

In the hydrodynamic regime, field theories typically have their boost symmetry spontaneously broken due to the presence of a thermal rest frame although the associated Goldstone field does not acquire independent dynamics. We show that this is not the case for Carrollian field theories where the boost Goldstone field plays a central role. This allows us to give a first-principles derivation of the equilibrium currents and dissipative effects of Carrollian fluids. We also demonstrate that the limit of vanishing speed of light of relativistic fluids is a special case of this class of Carrollian fluids. Our results shine light on the thermodynamic properties and thermal partition functions of Carrollian field theories.