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arXiv · 1408.6205

Geodesic completeness and homogeneity condition for cosmic inflation

Aindriu Conroy·Alexey S. Koshelev·Anupam Mazumdar
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Abstract

There are two disjointed problems in cosmology within General Relativity (GR), which can be addressed simultaneously by studying the nature of geodesics around $t\rightarrow 0$, where $t$ is the physical time. One is related to the past geodesic completeness of the inflationary trajectory due to the presence of a cosmological singularity, and the other one is related to the homogeneity condition required to inflate a local space-time patch of the universe. We will show that both the problems have a common origin, arising from how the causal structure of null and timelike geodesics are structured within GR. In particular, we will show how a non-local extension of GR can address both problems, while satisfying the null energy condition for the matter sources.

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Aindriu Conroy, Alexey S. Koshelev, Anupam Mazumdar. 2014-08-26. Geodesic completeness and homogeneity condition for cosmic inflation. https://doi.org/10.1103/physrevd.90.123525

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