Supersymmetric moduli stabilization and high-scale inflation

Wilfried Buchmuller,Clemens Wieck,Martin Wolfgang Winkler

doi:10.1016/j.physletb.2014.07.024

Wilfried Buchmuller, Clemens Wieck + Show 1 more

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https://doi.org/10.1016/j.physletb.2014.07.024

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Journal: Physics Letters B	Publication Date: Jul 22, 2014
Citations: 36	License type: cc-by

Affiliation: Deutsches Elektronen-Synchrotron DESY

Abstract

We study the back-reaction of moduli fields on the inflaton potential in generic models of F-term inflation. We derive the moduli corrections as a power series in the ratio of Hubble scale and modulus mass. The general result is illustrated with two examples, hybrid inflation and chaotic inflation. We find that in both cases the decoupling of moduli dynamics and inflation requires moduli masses close to the scale of grand unification. For smaller moduli masses the CMB observables are strongly affected.

Highlights

Supergravity F-term inflation is an attractive theoretical framework for describing the anisotropies of the cosmic microwave background radiation [1]
In chaotic inflation the leading order correction is suppressed by an additional power of H/mρ compared to hybrid inflation
The inflaton potential receives corrections due to a shift of the modulus minimum which can be written as a power series in the ratio of Hubble scale during inflation and modulus mass

Summary

Introduction

Supergravity F-term inflation is an attractive theoretical framework for describing the anisotropies of the cosmic microwave background radiation [1]. In the simple setup by KKLT the modulus mass and the barrier protecting the vacuum are proportional to the gravitino mass This leads to a tension between high-scale inflation and lowenergy supersymmetry breaking. As a possible alternative we study supersymmetric moduli stabilization, in the sense that all moduli masses are large and independent of the gravitino mass Examples of this type are ‘racetrack models’ where the height of the barrier protecting metastable Minkowski space can be arbitrarily large, independent of the scale of supersymmetry breaking [10]. In small-field inflation, such as hybrid inflation, this produces a linear term in the inflaton at leading order This is analogous to the effect of supersymmetry breaking which induces a linear term proportional to the gravitino mass [15]. The modulus-induced terms can have severe consequences for CMB observables in the case of a large Hubble scale during inflation, which is suggested by the recently released B-mode polarization data [20]

Supersymmetric moduli stabilization and inflation

Hybrid inflation

Chaotic inflation

Conclusion