Hydrodynamics, spin currents and torsion

Understand

We construct the canonical constitutive relations for a fluid description of a system with a spin current, valid in an arbitrary number of dimensions in the absence of parity breaking or time reversal breaking terms.

• Our study encompasses the hydrostatic partition function, the entropy current, Kubo formula, conformal invariance, and the effect of charge.
• At some stages of the computation we turn on a background torsion tensor which naturally couples to the spin current.