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arXiv · 1110.6205

Spherical `Top-Hat' Collapse in general Chaplygin gas dominated universes

R. A. A. Fernandes·J. P. M. de Carvalho·A. Yu. Kamenshchik·U. Moschella·A. da Silva
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Abstract

We expand previous works on the spherical `top-hat' collapse (SC-TH) framework in generalized Chaplygin gas (gCg) dominated universes. Here we allow the collapse in all energetic components within the system. We analyze the non-linear stages of collapse for various choices of parameter αof the gCg model introducing an exact formulation for the so-called effective sound speed, $c_{eff}^2$. We show that, within the SC-TH framework, the growth of the structure becomes faster with increasing values of α.

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R. A. A. Fernandes, J. P. M. de Carvalho, A. Yu. Kamenshchik, U. Moschella, A. da Silva. 2012-02-08. Spherical `Top-Hat' Collapse in general Chaplygin gas dominated universes. https://doi.org/10.1103/physrevd.85.083501

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