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arXiv · 1103.2276

Acoustics of tachyon Fermi gas

Ernst Trojan·George V. Vlasov
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Abstract

We consider a Fermi gas of free tachyons as a continuous medium and find whether it satisfies the causality condition. There is no stable tachyon matter with the particle density below critical value $n_T$ and the Fermi momentum $k_F<\sqrt{\frac 32}m$ that depends on the tachyon mass $m$. The pressure $P$ and energy density $E$ cannot be arbitrary small, but the situation $P>E$ is not forbidden. Existence of shock waves in tachyon gas is also discussed. At low density $n_T<n<3.45n_T$ the tachyon matter remains stable but no shock wave do survive.

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Ernst Trojan, George V. Vlasov. 2011-06-03. Acoustics of tachyon Fermi gas. https://doi.org/10.1103/physrevd.83.124013

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