36 citations
Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.
- Yamaguchi UniversityJP29 papers
- National Institute of TechnologyJP4 papers
- RIKEN Nishina CenterJP4 papers
- Kyushu UniversityJP3 papers
- National Institute of Technology, Kagoshima CollegeJP3 papers
- The University of OsakaJP3 papers
- Ibaraki UniversityJP2 papers
- Institute of Space and Astronautical ScienceJP2 papers
- Japan Aerospace Exploration AgencyJP2 papers
- National Astronomical Observatory of JapanJP2 papers
- National Institute of Information and Communications TechnologyJP2 papers
- Osaka Metropolitan UniversityJP2 papers
17 papers · 1 filter
Electric and dilatonic fields of a charged massive particle at rest in the field of a charged dilaton black hole
Nahomi Kan, Kiyoshi Shiraishi
We study linear-perturbation equations for the two-body system of a charged dilaton black hole, of which dilaton coupling constant is , and a static particle with mass , elec…
Spinorial Wheeler-DeWitt wave functions inside black hole horizons
Nahomi Kan, Takuma Aoyama, Kiyoshi Shiraishi
We revisit the solutions of the Wheeler-DeWitt (WDW) equation inside the horizons of spherical black holes and planar topological black holes in arbitrary dimensions. For these sys…
Classical and quantum bicosmology with noncommutativity
Nahomi Kan, Takuma Aoyama, Kiyoshi Shiraishi
Recently, Falomir, Gamboa, Mendez, Gondolo and Maldonado proposed a bicosmology scenario [1-4] for solving some cosmological problems related to inflation, dark matter, and thermal…
Third quantization for scalar and spinor wave functions of the Universe in an extended minisuperspace
Nahomi Kan, Takuma Aoyama, Taiga Hasegawa +1
We consider the third quantization in quantum cosmology of a minisuperspace extended by the Eisenhart-Duval lift. We study the third quantization based on both Klein-Gordon type an…
Eisenhart--Duval lift for minisuperspace quantum cosmology
Nahomi Kan, Takuma Aoyama, Taiga Hasegawa +1
We study covariant equations in quantum cosmology of an extended minisuperspace obtained by the Eisenhart--Duval lift. We find that a Dirac-type equation is naturally introduced in…
Isothermal spheres in general relativity and Horava-type gravity
Nahomi Kan, Kiyoshi Shiraishi
We construct a toy model for isothermal spheres in Horava gravity, which includes Einstein's gravity if a parameter is appropriately chosen. The equations for the isothermal sphere…
Calculations in induced gravity from higher-derivative field theories
Nahomi Kan, Kiyoshi Shiraishi
In this paper, we investigate Einstein's gravity induced from higher-derivative scalar field theories. We develop an approach utilizing an effective theory of multiple fields for t…
Equivalent Hamiltonian approach to quantum cosmology of integrable models
Nahomi Kan, Masashi Kuniyasu, Kiyoshi Shiraishi +1
We propose an approach to quantum cosmology of integrable models. To analyze the models with two dynamical variables, we introduce equivalent Hamiltonians in reduced phase spaces,…
Accelerating cosmologies in an integrable model with noncommutative minisuperspace variables
Nahomi Kan, Masashi Kuniyasu, Kiyoshi Shiraishi +1
We study classical and quantum noncommutative cosmology with a Liouville-type scalar degree of freedom. The noncommutativity is imposed on the minisuperspace variables through a de…
Classical and quantum cosmology of -essentially modified and pure gravity
Nahomi Kan, Kiyoshi Shiraishi, Mai Yashiki
We present a gravitational action with a modified higher order term of a combination of scalar curvature and Lagrangian density of a scalar field. This type of models has been cons…
An ostentatious model of cosmological scalar-tensor theory
Nahomi Kan, Kiyoshi Shiraishi
We consider a novel model of gravity with a scalar field described by the Lagrangian with higher order derivative terms in a cosmological context. The model has the same solution f…
Analytical Study of Charged Boson Stars with Large Scalar Self-couplings
Nahomi Kan, Kiyoshi Shiraishi
We give good approximate analytic solutions for spherical charged boson stars in the large scalar-self-coupling limit in general relativity. We show that if the charge and mass…
GR-GSG Hybrid Gravity
Nahomi Kan, Takuya Maki, Kiyoshi Shiraishi
We propose a model of gravity in which a General Relativity metric tensor and an effective metric generated from a single scalar formulated in Geometric Scalar Gravity are mixed. W…
Analytical Approximation for Newtonian Boson Stars in Four and Five Dimensions -- A Poor Person's Approach to Rotating Boson Stars
Nahomi Kan, Kiyoshi Shiraishi
In this paper, we study rotating boson stars in the large coupling limit as well as in the Newtonian limit. We investigate the equilibrium solutions in four and five dimensions by…
Generic Scalar Potentials in Geometric Scalar Gravity
Nahomi Kan, Kiyoshi Shiraishi
We discuss a generic form of the scalar potential appearing in the geometric scalar theory of gravity. We find the conditions on the potential by considering weak and strong gravit…
Critical Combinations of Higher Order Terms in Einstein-Maxwell theory and Compactification
Nahomi Kan, Kiyoshi Shiraishi
We discuss the role of a particular combination of higher derivative terms in higher dimensional theories, especially in the background of spontaneous compactification. We find tha…
A Model of BPS Black Holes in a Discrete Space
Nahomi Kan, Koichiro Kobayashi, Kiyoshi Shiraishi
We examine a model of BPS black holes lying on a discrete extra space. The geometry is obtained from the discretization of the harmonic equation. We study the scattering amplitudes…