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Generalized Chaplygin Gas, Accelerated Expansion and Dark Energy-Matter Unification

M. C. Bento·O. Bertolami·A. A. Sen
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Abstract

We consider the scenario emerging from the dynamics of a generalized $d$-brane in a $(d+1, 1)$ spacetime. The equation of state describing this system is given in terms of the energy density, $ρ$, and pressure, $p$, by the relationship $p = - A/ρ^α$, where $A$ is a positive constant and $0 < α\le 1$. We discuss the conditions under which homogeneity arises and show that this equation of state describes the evolution of a universe evolving from a phase dominated by non-relativistic matter to a phase dominated by a cosmological constant via an intermediate period where the effective equation of state is given by $p = αρ$.

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M. C. Bento, O. Bertolami, A. A. Sen. 2002-04-18. Generalized Chaplygin Gas, Accelerated Expansion and Dark Energy-Matter Unification. https://doi.org/10.1103/physrevd.66.043507

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