Asymptotic Limit for the Speed of Sound in a System of Relativistically Interacting Particles

Abstract

A relativistic many-body theory is used to evaluate the equation of state to lowest order in the weak coupling constant for a dense system of electrons and neutrinos interacting through the universal Fermi interaction. The asymptotic limit for the speed of sound $v_s<~\frac{c}{\sqrt{3}}$ is obtained; it is conjectured that a large class of relativistic interactions leads to the same limit.