Canonical and phenomenological formulations of spin hydrodynamics
Abstract
Two formulations of relativistic hydrodynamics of particles with spin 1/2 are compared. The first approach, dubbed the canonical one, uses expressions for the energy-momentum and spin tensors that have properties that follow a direct application of Noether's theorem, which yields a totally antisymmetric spin tensor. The other one is based on a simplified form of the spin tensor and is commonly used in the current literature under the name of a phenomenological approach. We show that these two frameworks are equivalent, i.e., they can be directly connected by a suitably defined pseudogauge transformation, only if the first framework is initially improved by a suitable modification of the energy-momentum tensor (addition of a divergence-free term that cannot be interpreted as a pseudogauge). Our analysis uses arguments related to the positivity of entropy production. The latter turns out to be equivalent for the improved canonical and phenomenological frameworks.
Keywords
Cite
@article{arxiv.2202.12609,
title = {Canonical and phenomenological formulations of spin hydrodynamics},
author = {Asaad Daher and Arpan Das and Wojciech Florkowski and Radoslaw Ryblewski},
journal= {arXiv preprint arXiv:2202.12609},
year = {2023}
}
Comments
Published in Physical Review C, journal reference: Phys. Rev. C 108, 024902 (2023). This manuscript matches the published version. 12 pages with no figures