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arXiv · 0910.3246

Transient cosmic acceleration from interacting fluids

Julio C. Fabris·Bernardo Fraga·Nelson Pinto-Neto·Winfried Zimdahl
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Abstract

Recent investigations seem to favor a cosmological dynamics according to which the accelerated expansion of the Universe may have already peaked and is now slowing down again \cite{sastaro}. As a consequence, the cosmic acceleration may be a transient phenomenon. We investigate a toy model that reproduces such a background behavior as the result of a time-dependent coupling in the dark sector which implies a cancelation of the "bare" cosmological constant. With the help of a statistical analysis of Supernova Type Ia (SNIa) data we demonstrate that for a certain parameter combination a transient accelerating phase emerges as a pure interaction effect.

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Julio C. Fabris, Bernardo Fraga, Nelson Pinto-Neto, Winfried Zimdahl. 2009-10-18. Transient cosmic acceleration from interacting fluids. https://doi.org/10.1088/1475-7516/2010/04/008

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