Thermal equivariance and its applications

I will describe how techniques from topological field theory and equivariant cohomology find a role in physical problems. I will define the notion of thermal equivariance which will involve gauging thermal diffeomorphisms, and argue that these constructions naturally lead to entropy being interpretable as a Noether current.  I will outline an application to constructing dissipative hydrodynamic effective actions, reproducing previously known facts about the admissible constitutive relations.