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arXiv · hep-th/0504168

Shift Symmetry and Inflation in Supergravity

Philippe Brax·Jerome Martin
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Abstract

We consider models of inflation in supergravity with a shift symmetry. We focus on models with one moduli and one inflaton field. The presence of this symmetry guarantees the existence of a flat direction for the inflaton field. Mildly breaking the shift symmetry using a superpotential which depends not only on the moduli but also on the inflaton field allows one to lift the inflaton flat direction. Along the inflaton direction, the eta-problem is alleviated. Combining the KKLT mechanism for moduli stabilization and a shift symmetry breaking superpotential of the chaotic inflation type, we find models reminiscent of ``mutated hybrid inflation'' where the inflationary trajectory is curved in the moduli--inflaton plane. We analyze the phenomenology of these models and stress their differences with both chaotic and hybrid inflation.

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Philippe Brax, Jerome Martin. 2005-04-20. Shift Symmetry and Inflation in Supergravity. https://doi.org/10.1103/physrevd.72.023518

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