Helical Inflation and Cosmic Strings

S. -H. Henry Tye; Sam S. C. Wong

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arXiv · 1404.6988

Helical Inflation and Cosmic Strings

S. -H. Henry Tye·Sam S. C. Wong

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Abstract

Recent BICEP2 detection of low-multipole B-mode polarization anisotropy in the cosmic microwave background radiation supports the inflationary universe scenario and suggests a large inflaton field range. The latter feature can be achieved with axion fields in the framework of string theory. We present such a helical model which naturally becomes a model with a single cosine potential, and which in turn reduces to the (quadratic) chaotic inflation model in the super-Planckian limit. The slightly smaller tensor/scalar ratio $r$ of models of this type provides a signature of the periodic nature of an axion potential. We present a simple way to quantify this distinctive feature. As axions are intimately related to strings/vortices and strings are ubiquitous in string theory, we explore the possibility that cosmic strings may be contributing to the B-mode polarization anisotropy observed.

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S. -H. Henry Tye, Sam S. C. Wong. 2014-06-26. Helical Inflation and Cosmic Strings. https://arxiv.org/abs/1404.6988

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