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arXiv · 1206.6374

Stable bounce and inflation in non-local higher derivative cosmology

Tirthabir Biswas·Alexey S. Koshelev·Anupam Mazumdar·Sergey Yu. Vernov
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Abstract

One of the greatest problems of primordial inflation is that the inflationary space-time is past-incomplete. This is mainly because Einstein's GR suffers from a space-like Big Bang singularity. It has recently been shown that ghost-free, non-local higher-derivative ultra-violet modifications of Einstein's gravity may be able to resolve the cosmological Big Bang singularity via a non-singular bounce. Within the framework of such non-local cosmological models, we are going to study both sub- and super-Hubble perturbations around an inflationary trajectory which is preceded by the Big Bounce in the past, and demonstrate that the inflationary trajectory has an ultra-violet completion and that perturbations do not suffer from any pathologies.

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Tirthabir Biswas, Alexey S. Koshelev, Anupam Mazumdar, Sergey Yu. Vernov. 2012-09-03. Stable bounce and inflation in non-local higher derivative cosmology. https://doi.org/10.1088/1475-7516%2F2012%2F08%2F024

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