Causality and the speed of sound
General Relativity and Quantum Cosmology
2008-11-26 v2 Astrophysics
High Energy Physics - Theory
Abstract
A usual causal requirement on a viable theory of matter is that the speed of sound be at most the speed of light. In view of various recent papers querying this limit, the question is revisited here. We point to various issues confronting theories that violate the usual constraint.
Keywords
Cite
@article{arxiv.gr-qc/0703121,
title = {Causality and the speed of sound},
author = {George Ellis and Roy Maartens and Malcolm MacCallum},
journal= {arXiv preprint arXiv:gr-qc/0703121},
year = {2008}
}
Comments
v2: additional discussion on models that appear to have superluminal signal speeds; version to appear in GRG