24 citations · 57 across the 5 of their papers we have counts for
6 papers
Dimensional (In)dependence of Lorentzian Quantum Cosmology
Masazumi Honda, Hiroki Matsui, Kota Numajiri +2
We study transition amplitudes of the quantum universe in -dimensional spacetime within the de Sitter minisuperspace approximation in Einstein gravity. Using the Lorentzian path…
Jackiw-Teitelboim Gravity and Lorentzian Quantum Cosmology
Masazumi Honda, Hiroki Matsui, Kota Numajiri +1
We directly evaluate the probability amplitudes in Jackiw-Teitelboim (JT) gravity using the Lorentzian path integral formulation. By imposing boundary conditions on the scale facto…
Boulware Vacuum vs. Regularity: Thoughts on Anomaly-Induced Effective Action
Kota Numajiri, Kazumasa Okabayashi, Shinji Mukohyama
We examine the vacuum state and its corresponding renormalized stress-energy tensor (RSET) in static horizonless regular spacetime in both two and four dimensions. Using the local…
Compact star in noninteger power model of gravity
Yong-Xiang Cui, Zu Yan, Kota Numajiri +2
We investigate compact stars in the noninteger power (NIP) model of gravity theory, which includes the higher-curvature correction to the Einstein-Hilbert action. The mass-r…
Revisiting compact star in gravity: Roles of chameleon potential and energy conditions
Kota Numajiri, Yong-Xiang Cui, Taishi Katsuragawa +1
We reexamine the static and spherical symmetric compact star configuration in the model of the gravity theory. With asymptotic solutions for the additional scalar degr…
Compact Star in General Gravity: Inevitable Degeneracy Problem and Non-Integer Power Correction
Kota Numajiri, Taishi Katsuragawa, Shin'ichi Nojiri
We investigate a compact star in the general gravity. Developing a novel formulation in the spherically symmetric and static space-time with the matter, we confirm that an a…