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arXiv · 1405.5688

Clustering GCG: a viable option for unified dark matter-dark energy?

Sumit Kumar·Anjan A. Sen
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Abstract

We study the clustering Generalized Chaplygin Gas (GCG) as a possible candidate for dark matter-dark energy unification. The vanishing speed of sound ($c_{s}^2 = 0$) for the GCG fluid can be obtained by incorporating higher derivative operator in the original K-essence Lagrangian. The evolution of the density fluctuations in the GCG+Baryon fluid is studied in the linear regime. The observational constraints on the model are obtained using latest data from SNIa, $H(z)$, BAO and also for the $fσ_{8}$ measurements. The matter power spectra for the allowed parameter values are well behaved without any unphysical features.

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Sumit Kumar, Anjan A. Sen. 2014-10-21. Clustering GCG: a viable option for unified dark matter-dark energy?. https://doi.org/10.1088/1475-7516%2F2014%2F10%2F036

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