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Density perturbations in an Universe dominated by the Chaplygin gas

J. C. Fabris·S. V. B. Goncalves·P. E. de Souza
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Abstract

We study the fate of density perturbations in an Universe dominate by the Chaplygin gas, which exhibit negative pressure. We show that it is possible to obtain the value for the density contrast observed in large scale structure of the Universe by fixing a free parameter in the equation of state of this gas. The negative character of pressure must be significant only very recently.

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J. C. Fabris, S. V. B. Goncalves, P. E. de Souza. 2001-03-22. Density perturbations in an Universe dominated by the Chaplygin gas. https://doi.org/10.1023/a%3A1015266421750

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