24 citations · 79 across the 8 of their papers we have counts for
5 papers · 1 filter
Ghost-free scalar-fermion interactions
Rampei Kimura, Yuki Sakakihara, Masahide Yamaguchi
We discuss a covariant extension of interactions between scalar fields and fermions in a flat space-time. We show, in a covariant theory, how to evade fermionic ghosts appearing be…
Ghost free boson-fermion co-existence system
Rampei Kimura, Yuki Sakakihara, Masahide Yamaguchi
We study co-existence system of both bosonic and fermionic degrees of freedom. For such system with up to first derivatives in Lagrangian, we find Ostrogradsky-type ghost-free cond…
Primordial fluctuations from inflation in dRGT bimetric theory of gravity
Yuki Sakakihara, Takahiro Tanaka
We investigate primordial gravitational waves and curvature perturbations in de Rham-Gabadadze-Tolley (dRGT) bimetric gravity. We evaluate the power-spectra in the leading order in…
Primordial Gravitational Waves in Bimetric Gravity
Yuki Sakakihara, Jiro Soda
We study primordial tensor power-spectra generated during inflation in bimetric gravity. More precisely, we examine a homogeneous expanding spacetime in a minimal bimetric model wi…
On Cosmic No-hair in Bimetric Gravity and the Higuchi Bound
Yuki Sakakihara, Jiro Soda, Tomohiro Takahashi
We study the cosmic no-hair in the presence of spin-2 matter, i.e. in bimetric gravity. We obtain stable de Sitter solutions with the cosmological constant in the physical sector a…