Dirac-Born-Infeld-Einstein theory with Weyl invariance

TL;DR

This paper explores a Weyl invariant extension of Dirac-Born-Infeld gravity, demonstrating how it can facilitate vector inflation by removing scalar degrees of freedom and inducing vector field mass and couplings.

Contribution

It introduces a novel Weyl invariant Dirac-Born-Infeld gravity model that supports vector inflation and clarifies the role of metric choice in scalar degree removal.

Findings

Scalar degree of freedom is removed by metric choice.

Vector field acquires mass through the theory.

Nonminimal couplings between vector fields and curvature are induced.

Abstract

Weyl invariant gravity has been investigated as the fundamental theory of the vector inflation. Accordingly, we consider a Weyl invariant extension of Dirac-Born-Infeld type gravity. We find that an appropriate choice of the metric removes the scalar degree of freedom which is at the first sight required by the local scale invariance of the action, and then a vector field acquires mass. Then nonminimal couplings of the vector field and curvatures are induced. We find that the Dirac-Born-Infeld type gravity is a suitable theory to the vector inflation scenario.