117 citations · 203 across the 8 of their papers we have counts for
8 papers
Kinetic equation for Lifshitz scalar
Shinji Mukohyama, Yota Watanabe
Employing the method of Wigner functions on curved spaces, we study classical kinetic (Boltzmann-like) equations of distribution functions for a real scalar field with the Lifshitz…
Stable cosmology in chameleon bigravity
Antonio De Felice, Shinji Mukohyama, Michele Oliosi +1
The recently proposed chameleonic extension of bigravity theory, by including a scalar field dependence in the graviton potential, avoids several fine-tunings found to be necessary…
Solving the flatness problem with an anisotropic instanton in Hořava-Lifshitz gravity
Sebastian F. Bramberger, Andrew Coates, João Magueijo +3
In Hořava-Lifshitz gravity a scaling isotropic in space but anisotropic in spacetime, often called anisotropic scaling with the dynamical critical exponent z=3, lies at the base of…
Where does curvaton reside? Differences between bulk and brane frames
François Larrouturou, Shinji Mukohyama, Ryo Namba +1
Some classes of inflationary models naturally introduce two distinct metrics/frames, and their equivalence in terms of observables has often been put in question. D-brane inflation…
Is the DBI scalar field as fragile as other -essence fields?
Shinji Mukohyama, Ryo Namba, Yota Watanabe
Caustic singularity formations in shift-symmetric -essence and Horndeski theories on a fixed Minkowski spacetime were recently argued. In dimensions, this singularity is the…
Ghost inflation and de Sitter entropy
Sadra Jazayeri, Shinji Mukohyama, Rio Saitou +1
In the setup of ghost condensation model the generalized second law of black hole thermodynamics can be respected under a radiatively stable assumption that couplings between the f…
Derivative-dependent metric transformation and physical degrees of freedom
Guillem Domènech, Shinji Mukohyama, Ryo Namba +3
We study metric transformations which depend on a scalar field and its first derivatives and confirm that the number of physical degrees of freedom does not change under such t…
Hamiltonian analysis of nonprojectable Hořava-Lifshitz gravity with symmetry
Shinji Mukohyama, Ryo Namba, Rio Saitou +1
We study the nature of constraints and count the number of degrees of freedom in the nonprojectable version of the extension of Hořava-Lifshitz gravity, using the standard m…