Kinetic approach to polarization-vorticity coupling and hydrodynamics with spin

Abstract: Recently introduced equilibrium Wigner functions for spin-one-half particles are used in the semiclassical kinetic equations to study the relation between spin polarization and vorticity. It is found, in particular, that such a framework does not necessarily imply that the thermal-vorticity and spin polarization tensors are equal. Subsequently, a procedure to formulate the hydrodynamic framework for particles with spin-one-half, based on the semiclassical expansion, is outlined.