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arXiv · 1707.05830

Fibre Inflation and $α$-attractors

Renata Kallosh·Andrei Linde·Diederik Roest·Alexander Westphal·Yusuke Yamada
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Abstract

Fibre inflation is a specific string theory construction based on the Large Volume Scenario that produces an inflationary plateau. We outline its relation to $α$-attractor models for inflation, with the cosmological sector originating from certain string theory corrections leading to $α=2$ and $α=1/2$. Above a certain field range, the steepening effect of higher-order corrections leads first to the breakdown of single-field slow-roll and after that to the onset of 2-field dynamics: the overall volume of the extra dimensions starts to participate in the effective dynamics. Finally, we propose effective supergravity models of fibre inflation based on an ${\overline {D3}}$ uplift term with a nilpotent superfield. Specific moduli dependent $\overline {D3}$ induced geometries lead to cosmological fibre models but have in addition a de Sitter minimum exit. These supergravity models motivated by fibre inflation are relatively simple, stabilize the axions and disentangle the Hubble parameter from supersymmetry breaking.

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Renata Kallosh, Andrei Linde, Diederik Roest, Alexander Westphal, Yusuke Yamada. 2017-12-26. Fibre Inflation and $α$-attractors. https://doi.org/10.1007/jhep02(2018)117

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