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arXiv · gr-qc/0703121

Causality and the speed of sound

George Ellis·Roy Maartens·Malcolm MacCallum
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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.

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George Ellis, Roy Maartens, Malcolm MacCallum. 2007-05-29. Causality and the speed of sound. https://doi.org/10.1007/s10714-007-0479-2

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