F-term hybrid inflation in effective supergravity theories Original Research Article

We show that a particular class of effective low energy supergravity theories motivated by string theory can provide a promising framework for models of hybrid inflation in which the potential energy which drives inflation originates from the F-term of the effective supergravity theory. In the class of models considered the inflaton is protected from receiving mass during inflation by a generalisation of the Heisenberg symmetry present in no-scale supergravity models. The potential during inflation takes the positive definite form V ∼ |FS|2 + |FT|2 − 3, which allows the possibili that V ⪡ m322MP2 through the cancelation of the positive dilaton and moduli contribution against the negative term. We discuss a toy example where this is realised, then describe the application of this result to realistic models focusing on a particular example in which the μ problem and the strong CP problem are addressed.