41 citations · 62 across the 4 of their papers we have counts for
8 papers · 1 filter
Past extendibility and initial singularity in Friedmann-Lemaître-Robertson-Walker and Bianchi I spacetimes
Kimihiro Nomura, Daisuke Yoshida
We study past-directed extendibility of Friedmann-Lemaître-Robertson-Walker (FLRW) and Bianchi type I spacetimes with a scale factor vanishing in the past. We give criteria for det…
Theories with limited extrinsic curvature and a nonsingular anisotropic universe
Yuki Sakakihara, Daisuke Yoshida, Kazufumi Takahashi +1
We propose a class of theories that can limit scalars constructed from the extrinsic curvature. Applied to cosmology, this framework allows us to control not only the Hubble parame…
Stability of magnetic black holes in general nonlinear electrodynamics
Kimihiro Nomura, Daisuke Yoshida, Jiro Soda
We study the perturbative stability of magnetic black holes in a general class of nonlinear electrodynamics, where the Lagrangian is given by a general function of the field streng…
Cuscuton gravity as a classically stable limiting curvature theory
Jerome Quintin, Daisuke Yoshida
Finding effective theories of modified gravity that can resolve cosmological singularities and avoid other physical pathologies such as ghost and gradient instabilities has turned…
Ghost-free resummation of gravitational interactions of a 2-form gauge field
Kazufumi Takahashi, Daisuke Yoshida
We find that the recently-proposed ghost-free interaction of a 2-form gauge field in four dimensions, which contains derivative couplings in a nonperturbative manner, can be regard…
Stable cosmological solutions in degenerate theory of gravity
Ryotaro Kase, Rampei Kimura, Atsushi Naruko +1
We study cosmological applications of extended vector-tensor theories, whose Lagrangians contain up to two derivatives with respect to metric and vector field. We derive background…