Speaker
Benjamin Withers
Description
As an effective theory constructed in a gradient expansion, relativistic hydrodynamics is fixed by symmetries up to a set of transport coefficients. I will utilise bootstrap techniques to rule out theories that are inconsistent with microscopic causality. What remains is a universal convex geometry in the space of transport coefficients, "the hydrohedron”. I will also discuss the necessary role played by non-hydrodynamic degrees of freedom in achieving causality. Based on 2212.07434 and 2305.07703.
