Vector Field in Cosmic Inflation: Construction and Analysis of Stable Models

Abstract

We investigate the possibility of using a vector field to drive anisotropic cosmic inflation in contrast with the isotropic accelerated expansion driven by scalar field. The realization of such vector field models during inflation provides a promising link to the observed large scale Cosmic Microwave Background anomalies. Despite being a close upgraded step from the scalar field, the vector field models are troubled with instabilities due to the presence of ghost. In this work, we construct and analyze stable vector field models in simple form using ideas from chaotic inflation. We obtain stable evolution of slow-roll inflationary period driven by a vector field and present also different graceful exit scenarios.