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arXiv · 1205.3768

FRW type of cosmology with a Chaplygin gas

D. Panigrahi·S. Chatterjee
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Abstract

The evolution of a universe modelled as a mixture of generalised Chaplygin gas and ordinary matter field is studied for a Robertson Walker type of spacetime. This model could interpolate periods of a radiation dominated, matter dominated and a cosmological constant dominated universe. Depending on the arbitrary constants appearing in our theory the instant of flip changes. Interestingly we also get a bouncing model when the signature of one of the constants changes. The velocity of sound may become imaginary under certain situations pointing to a perturbative state and consequently the possibility of structure formation. We also discuss the whole situation in the backdrop of wellknown Raychaudhury equation and a comparison is made with the previous results.

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D. Panigrahi, S. Chatterjee. 2012-10-04. FRW type of cosmology with a Chaplygin gas. https://doi.org/10.1142/s0218271812500794

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