55 citations · 127 across the 4 of their papers we have counts for
4 papers
Tracker and scaling solutions in DHOST theories
Noemi Frusciante, Ryotaro Kase, Kazuya Koyama +2
In quadratic-order degenerate higher-order scalar-tensor (DHOST) theories compatible with gravitational-wave constraints, we derive the most general Lagrangian allowing for tracker…
Absence of solid angle deficit singularities in beyond-generalized Proca theories
Lavinia Heisenberg, Ryotaro Kase, Shinji Tsujikawa
In Gleyzes-Langlois-Piazza-Vernizzi (GLPV) scalar-tensor theories, which are outside the domain of second-order Horndeski theories, it is known that there exists a solid angle defi…
Cosmology in generalized Horndeski theories with second-order equations of motion
Ryotaro Kase, Shinji Tsujikawa
We study the cosmology of an extended version of Horndeski theories with second-order equations of motion on the flat Friedmann-Lemaître-Robertson-Walker (FLRW) background. In addi…
Effective field theory of modified gravity on the spherically symmetric background: leading order dynamics and the odd-type perturbations
Ryotaro Kase, László Árpád Gergely, Shinji Tsujikawa
We consider perturbations of a static and spherically symmetric background endowed with a metric tensor and a scalar field in the framework of the effective field theory of modifie…