63 citations · 106 across the 5 of their papers we have counts for
5 papers
Pole inflation in Jordan frame supergravity
Ken'ichi Saikawa, Masahide Yamaguchi, Yasuho Yamashita +1
We investigate inflation models in Jordan frame supergravity, in which an inflaton non-minimally couples to the scalar curvature. By imposing the condition that an inflaton would h…
Constraint on ghost-free bigravity from gravitational Cherenkov radiation
Rampei Kimura, Takahiro Tanaka, Kazuhiro Yamamoto +1
We investigate gravitational Cherenkov radiation in a healthy branch of background solutions in the ghost-free bigravity model. In this model, because of the modification of disper…
Bigravity from gradient expansion
Yasuho Yamashita, Takahiro Tanaka
We discuss how the ghost-free bigravity coupled with a single scalar field can be derived from a braneworld setup. We consider DGP two-brane model without radion stabilization. The…
Appearance of Boulware-Deser ghost in bigravity with doubly coupled matter
Yasuho Yamashita, Antonio De Felice, Takahiro Tanaka
We discuss the ghost freeness in the case when we add matter coupled to two metrics to the ghost-free bigravity. In this paper we show that the Boulware-Deser ghost generally reviv…
Mapping de Rham-Gabadadze-Tolley bigravity into braneworld setup
Yasuho Yamashita, Takahiro Tanaka
We discuss whether or not bigravity theory can be embedded into the braneworld setup. As a candidate, we consider Dvali-Gabadadze-Porrati two-brane model with the Goldberger-Wise r…