Supersymmetric topological inflation model

We propose a topological inflation model in supergravity. In this model, the vacuum expectation value (VEV) of a scalar field takes a value much larger than the gravitational scale M(G)similar or equal to2.4x10(18) GeV, which is large enough to cause topological inflation. On the other hand, expansions of the Kahler potential and the superpotential beyond the gravitational scale are validated by the introduction of a Nambu-Goldstone-like shift symmetry. Thus, topological inflation inevitably takes place in our model.