Tachyonic thermal excitations and causality

Ernst Trojan; George V. Vlasov

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arXiv · 1106.5857

Tachyonic thermal excitations and causality

Ernst Trojan·George V. Vlasov

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Abstract

We consider an ideal Fermi gas of tachyonic thermal excitations as a continuous medium and establish when it satisfies the causality condition. At high temperature the sound speed is always subluminal $c_s<1$, but there is no stable form of tachyon matter below the critical temperature $T_c<0.23m$ that depends on the tachyon mass $m$. The pressure $P$ and energy density $E$ cannot be arbitrary small, but $P$ can exceed $E$, and $P=2.36E$ when $T\rightarrow T_c$.

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Ernst Trojan, George V. Vlasov. 2011-10-08. Tachyonic thermal excitations and causality. https://arxiv.org/abs/1106.5857

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