J. Gariel et G. Ledenmat, RELATIONSHIP BETWEEN 2 THEORIES OF DISSIPATIVE RELATIVISTIC HYDRODYNAMICS APPLIED TO COSMOLOGY, Physical review. D. Particles and fields, 50(4), 1994, pp. 2560-2566
We compare Israel's relativistic causal theory of transient effects wi
th the relativistic extended irreversible thermodynamics of Pavon, Jou
, and Casas-Vasquez, applying both to the case of cosmic fluid with bu
lk viscosity only. They are completely equivalent up to the first orde
r in the parameter characterizing the departure from equilibrium. We s
how, if certain relations between the main variables of the two theori
es hold, that they are also equivalent up to the second order in this
parameter. We also extend up to any order Israel's theory and give the
relations permitting again the equivalence between the two theories i
n this general case. Some cosmological consequences are discussed.