Linearized dispersion relations in viscous relativistic hydrodynamics

PERNA, GUILLERMO; CALZETTA, ESTEBAN

PHYSICAL REVIEW D - PARTICLE AND FILDS

APS

Lugar: Ridge; Año: 2021 vol. 104 p. 1 - 20

0556-2821

We compute the dispersion relations for scalar, vector and tensor modes of a viscous relativistic fluid,linearized around an equilibrium solution, for a divergence type theory (which, in the linearized theory,includes Israel-Stewart theory and anisotropic hydrodynamics as particular cases) and contrast them to thecorresponding results derived from kinetic theory under the relaxation time approximation, and from causalfirst order theories.We conclude that all approaches give similar dynamics for the scalar and vector modes,while the particular divergence type theory presented here also contains propagating damped tensor waves,in agreement with kinetic theory. Nonhydrodynamic tensor modes are also a feature of holographic fluids.These results support the application of hydrodynamics in problems involving the interaction betweenfluids and gravitational waves.