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arXiv · 1505.00228

Criticality and Big Brake singularities in the tachyonic evolutions of closed Friedmann universes with cold dark matter

Zsolt Horváth·Zoltán Keresztes·Alexander Yu. Kamenshchik·László Á. Gergely
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Abstract

The evolution of a closed Friedmann universe filled by a tachyon scalar field with a trigonometric potential and cold dark matter (CDM) is investigated. A subset of the evolutions consistent to 1$σ$ confidence level with the Union 2.1 supernova data set is identified. The evolutions of the tachyon field are classified. Some of them evolve into a de Sitter attractor, while others proceed through a pseudo-tachyonic regime into a sudden future singularity. Critical evolutions leading to Big Brake singularities in the presence of CDM are found and a new type of cosmological evolution characterized by singularity avoidance in the pseudo-tachyon regime is presented.

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Zsolt Horváth, Zoltán Keresztes, Alexander Yu. Kamenshchik, László Á. Gergely. 2015-05-01. Criticality and Big Brake singularities in the tachyonic evolutions of closed Friedmann universes with cold dark matter. https://doi.org/10.1103/physrevd.91.103513

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