Geodesic Completeness in General Cosmological Scenarios

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Bibliographic Details
Main Author:	Kinney, William H.
Format:	Preprint
Published:	2026
Subjects:	General Relativity and Quantum Cosmology Cosmology and Nongalactic Astrophysics
Online Access:	Acceder al recurso
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_version_	1866913055672107008
author	Kinney, William H.
author_facet	Kinney, William H.
contents	The well-known Borde-Guth-Vilenkin Theorem shows that inflationary spacetimes are generically geodesically past-incomplete, necessitating the existence of a pre-inflationary boundary of some sort, possibly singular. I discuss the generalization of the BGV theorem to spacetimes beyond inflation, including inhomogeneous and cyclic models. As an example, I show that the cyclic model proposed by Ijjas and Steinhardt is geodesically incomplete.
format	Preprint
id	arxiv_https___arxiv_org_abs_2604_20809
institution	arXiv
publishDate	2026
record_format	arxiv
spellingShingle	Geodesic Completeness in General Cosmological Scenarios Kinney, William H. General Relativity and Quantum Cosmology Cosmology and Nongalactic Astrophysics The well-known Borde-Guth-Vilenkin Theorem shows that inflationary spacetimes are generically geodesically past-incomplete, necessitating the existence of a pre-inflationary boundary of some sort, possibly singular. I discuss the generalization of the BGV theorem to spacetimes beyond inflation, including inhomogeneous and cyclic models. As an example, I show that the cyclic model proposed by Ijjas and Steinhardt is geodesically incomplete.
title	Geodesic Completeness in General Cosmological Scenarios
topic	General Relativity and Quantum Cosmology Cosmology and Nongalactic Astrophysics
url	https://arxiv.org/abs/2604.20809

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