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arXiv · 2309.11703

Causality and classical dispersion relations

Raphael E. Hoult·Pavel Kovtun
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Abstract

We explore the consequences of relativistic causality and covariant stability for short-wavelength dispersion relations in classical systems. For excitations described by a finite number of partial differential equations, as is the case in relativistic hydrodynamics, we give causality and covariant stability constraints on the excitation's frequency at large momenta.

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Raphael E. Hoult, Pavel Kovtun. 2024-02-28. Causality and classical dispersion relations. https://doi.org/10.1103/physrevd.109.046018

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