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arXiv · 0710.0999

Particle Production in an expanding universe dominated by dark energy fluid

A. B. Batista·J. C. Fabris·M. J. S. Houndjo
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Abstract

We investigate the fate of particle production in an expanding universe dominated by a perfect fluid with equation of state $p = αρ$. The rate of particle production, using the Bogolioubov coefficients, are determined exactly for any value of $α$ in the case of a flat universe. When the strong energy condition is satisfied, the rate of particle production decreases as time goes on, in agreement to the fact that the four-dimensional curvature decreases with the expansion; the opposite occurs when the strong energy condition is violated. In the phantomic case, the rate of particle production diverges in a finite time. This may lead to a backreaction effect, leading to the avoidance of the big rip singularity, specially if $- 1 > α> - {5/3}$.

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A. B. Batista, J. C. Fabris, M. J. S. Houndjo. 2007-10-04. Particle Production in an expanding universe dominated by dark energy fluid. https://doi.org/10.1134/s0202289308020035

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