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arXiv · 1904.09961

Nonsingular bouncing cosmology from general relativity

F. R. Klinkhamer·Z. L. Wang
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Abstract

We investigate a particular type of classical nonsingular bouncing cosmology, which results from general relativity if we allow for degenerate metrics. The simplest model has a matter content with a constant equation-of-state parameter and we get the modified Hubble diagrams for both the luminosity distance and the angular diameter distance. Based on these results, we present a Gedankenexperiment to determine the length scale of the spacetime defect which has replaced the big bang singularity. A possibly more realistic model has an equation-of-state parameter which is different before and after the bounce. This last model also provides an upper bound on the defect length scale.

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F. R. Klinkhamer, Z. L. Wang. 2019-04-22. Nonsingular bouncing cosmology from general relativity. https://doi.org/10.1103/physrevd.100.083534

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