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arXiv · 0909.0866

More about the Tolman-Oppenheimer-Volkoff equations for the generalized Chaplygin gas

V. Gorini·A. Yu. Kamenshchik·U. Moschella·O. F. Piattella·A. A. Starobinsky
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Abstract

We investigate the Tolman-Oppenheimer-Volkoff equations for the generalized Chaplygin gas with the aim of extending the findings of V. Gorini, U. Moschella, A. Y. Kamenshchik, V. Pasquier, and A. A. Starobinsky [Phys. Rev. D {\bf 78}, 064064 (2008)]. We study both the standard case, where we reproduce some previous results, and the phantom case. In the phantom case we show that even a superluminal group velocity arising for $α> 1$ cannot prevent the divergence of the pressure at a finite radial distance. Finally, we investigate how a modification of the generalized Chaplygin gas equation of state, required by causality arguments at densities very close to $Λ$, affects the results found so far.

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V. Gorini, A. Yu. Kamenshchik, U. Moschella, O. F. Piattella, A. A. Starobinsky. 2009-12-03. More about the Tolman-Oppenheimer-Volkoff equations for the generalized Chaplygin gas. https://doi.org/10.1103/physrevd.80.104038

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