On the hyperbolicity and causality of the relativistic Euler system under the kinetic equation of state

摘要

We show that a pair of conjectures raised in [11] concerning the constructionof normal solutions to the relativistic Boltzmann equation are valid. Thisensures that the results in [11] hold for any range of positive temperaturesand that the relativistic Euler system under the kinetic equation of state ishyperbolic and the speed of sound cannot overcome $c/\sqrt{3}$.