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Challenges for Inflationary Cosmology

Robert H. Brandenberger
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Abstract

Inflationary cosmology has provided a predictive and phenomenologically very successful scenario for early universe cosmology. Attempts to implement inflation using scalar fields, however, lead to models with serious conceptual problems. I will discuss some of the problems, explain why string theory could provide solutions to a subset of these problems, and give a brief overview of ``string gas cosmology'', one of the approaches to merge string theory and early universe cosmology.

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Robert H. Brandenberger. 2005-01-09. Challenges for Inflationary Cosmology. https://arxiv.org/abs/astro-ph/0411671

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