7 papers
Constraining Spatial Curvature with Priors from Swampland Conjectures
Simran Arora, Hun Jang, Shinji Mukohyama
We study a string-motivated theoretical prior on the quintessential dark energy model with exponential potential, \( V(ϕ) = V_0 e^{-λϕ} \), allowing for non-zero spatial curvature.…
Space- vs Time-dependence in taming the infrared instability of projectable Hořava Gravity
Shinji Mukohyama, Jury Radkovski, Sergey Sibiryakov
Minkowski spacetime exhibits infrared instability in projectable Ho\v rava gravity in (3+1) dimensions. To be phenomenologically viable, the instability should be either hidden by…
Propagation and polarization of gravitational waves on curved spacetime backgrounds in Einstein-Æther theory
Yu-Qi Dong, Shinji Mukohyama, Yu-Xiao Liu
We analyze the propagation and polarization properties of high-frequency gravitational waves in Einstein-Æther theory on vorticity-free and slowly-varying backgrounds at both leadi…
Macroscopic backreaction of the trace anomaly on classical vacuum backgrounds
Raúl Carballo-Rubio, Francesco Di Filippo, Shinji Mukohyama +1
We study the backreaction of quantum fields in the Boulware vacuum state on the Schwarzschild geometry, using the Riegert--Mottola--Vaulin renormalized stress-energy tensor derived…
On the regularity of deformed extremal horizons
Francesco Di Filippo, Shinji Mukohyama, José M. M. Senovilla
It has recently been argued that extremal black holes can act as amplifiers of new physics, due to horizon instabilities that enhance the effects of ultraviolet corrections. In thi…
Linear Higher-Order Maxwell-Einstein-Scalar Theories
Mohammad Ali Gorji, Shinji Mukohyama, Pavel Petrov +1
In the context of the Higher-Order Maxwell-Einstein-Scalar (HOMES) theories, which are invariant under spacetime diffeomorphisms and gauge symmetry, we study two broad subcl…