Bianchi type I expanding universe in Weyl-invariant massive gravity

Abstract

We will study the cosmological evolutions of a Weyl-invariant de Rham, Gabadadze, and Tolley (dRGT) massive gravity theory with a general fiducial metric. In the unitary gauge, this model is equivalent to a massive gauge field coupled to the dRGT massive gravity model. The massive gravity terms will serve as an effective cosmological constant for all metric spaces if the fiducial metric is treated as an auxiliary field. A further discussion will also be addressed on the bimetric theory. In particular, we will discuss the role played by the Weyl vector boson in Bianchi type I expanding space.