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arXiv · hep-th/0205140

Accelerated Universe from Modified Chaplygin Gas and Tachyonic Fluid

H. B. Benaoum
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Abstract

A cosmological model with an exotic fluid is investigated. We show that the equation of state of this ``modified Chaplygin'' gas can describe the current accelerated expansion of the universe. We then reexpress it as FRW cosmological model containing a scalar field $ϕ$ and find its self--interacting potential. Moreover motivated by recent works of Sen [sen1, sen2] and Padmanbhan [pad] on tachyon field theory, a map for this exotic fluid as a normal scalar field $ϕ$ with Lagrangian ${\cal L}_ϕ = \frac{\dotϕ^2}{2} - U (ϕ)$ to the tachyonic field $T$ with Lagrangian ${\cal L}_{T} = - V(T) \sqrt{1 - \dot{T}^2}$ is obtained.

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H. B. Benaoum. 2002-05-14. Accelerated Universe from Modified Chaplygin Gas and Tachyonic Fluid. https://doi.org/10.3390/universe8070340

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