51 citations · 265 across the 23 of their papers we have counts for
23 papers
Exact solutions for static spherically symmetric spacetime with a perfect fluid in Rastall theory
Yoshimune Tomikawa, Ichika Obara, Takumi Orimo
In general relativity, exact Liouvillian solutions for a static and spherically symmetric spacetime with a perfect fluid and the equation of state are known only for $…
Quasilocal inequalities for attractive gravity probe surface
Tetsuya Shiromizu, Keisuke Izumi, Hirotaka Yoshino +1
We discuss the local and quasilocal properties of the loosely trapped surface (LTS) and the attractive gravity probe surface (AGPS), which have been proposed to characterize the st…
Loosely trapped surface for slowly rotating black hole
Keisuke Izumi, Tetsuya Shiromizu, Daisuke Yoshida +2
We construct the marginal loosely trapped surface (marginal LTS) for the Kerr spacetime with a small Kerr parameter perturbatively, where the LTS condition is saturated. An LTS is…
Attractive gravity probe surface in Einstein-Maxwell system
Kangjae Lee, Keisuke Izumi, Tetsuya Shiromizu +2
We derive areal inequalities for five types of attractive gravity probe surfaces, which were proposed by us in order to characterize the strength of gravity in different ways inclu…
Asymptotic behavior of null geodesics near future null infinity IV: Null-access theorem for generic asymptotically flat spacetime
Masaya Amo, Keisuke Izumi, Yoshimune Tomikawa +2
In our previous papers [arXiv:2106.03150, arXiv:2110.10917, arXiv:2208.00822], we analyzed the asymptotic behavior of future directed null geodesics near future null infinity and t…
A generalization of photon sphere based on escape/capture cone
Masaya Amo, Keisuke Izumi, Hirotaka Yoshino +2
In asymptotically flat spacetimes, bearing the null geodesics reaching the future null infinity in mind, we propose new concepts, the "dark horizons" as generalizations of the phot…
Attractive gravity probe surfaces in higher dimensions
Keisuke Izumi, Yoshimune Tomikawa, Tetsuya Shiromizu +1
A generalization of the Riemannian Penrose inequality in -dimensional space () is done. We introduce a parameter () indicating the streng…
Asymptotic behavior of null geodesics near future null infinity. III. Photons towards inward directions
Masaya Amo, Keisuke Izumi, Yoshimune Tomikawa +2
A new sufficient condition for photons emitted near future null infinity to reach future null infinity is derived by studying null geodesics in the Bondi coordinates in asymptotica…
Four types of attractive gravity probe surfaces
Kangjae Lee, Tetsuya Shiromizu, Keisuke Izumi +2
We reexamine the concept of the attractive gravity probe surface recently proposed as an indicator for strength of gravity. Then, we propose three new variant concepts and show ref…
Asymptotic behavior of null geodesics near future null infinity II: curvatures, photon surface and dynamically transversely trapping surface
Masaya Amo, Tetsuya Shiromizu, Keisuke Izumi +2
Bearing in mind our previous study on asymptotic behavior of null geodesics near future null infinity, we analyze the behavior of geometrical quantities such as a certain extrinsic…
On uniqueness of static spacetime with conformal scalar in higher dimensions
Keisuke Izumi, Yoshimune Tomikawa, Tetsuya Shiromizu
We discuss the uniqueness of asymptotically flat and static spacetimes in the -dimensional Einstein-conformal scalar system. This theory potentially has a singular point in the…
Divergence equations and uniqueness theorem of static spacetimes with conformal scalar hair
Takeshi Shinohara, Yoshimune Tomikawa, Keisuke Izumi +1
We reexamine the Israel-type proof of the uniqueness theorem of the static spacetime outside the photon surface in the Einstein-conformal scalar system. We derive in a systematic f…
Asymptotic behavior of null geodesics near future null infinity: Significance of gravitational waves
Masaya Amo, Keisuke Izumi, Yoshimune Tomikawa +2
We investigate the behavior of null geodesics near future null infinity in asymptotically flat spacetimes. In particular, we focus on the asymptotic behavior of null geodesics that…
Area bound for surfaces in generic gravitational field
Keisuke Izumi, Yoshimune Tomikawa, Tetsuya Shiromizu +1
We define an attractive gravity probe surface (AGPS) as a compact 2-surface with positive mean curvature satisfying (for a constant ) in t…
Loosely trapped surface and dynamically transversely trapping surface in Einstein-Maxwell system
Kangjae Lee, Tetsuya Shiromizu, Hirotaka Yoshino +2
We study the properties of the loosely trapped surface (LTS) and the dynamically transversely trapping surface (DTTS) in Einstein-Maxwell systems. These concepts of surfaces were p…
Formation of dynamically transversely trapping surfaces and the stretched hoop conjecture
Hirotaka Yoshino, Keisuke Izumi, Tetsuya Shiromizu +1
A dynamically transversely trapping surface (DTTS) is a new concept of an extension of a photon sphere that appropriately represents a strong gravity region and has close analogy w…
Transversely trapping surfaces: Dynamical version
Hirotaka Yoshino, Keisuke Izumi, Tetsuya Shiromizu +1
We propose new concepts, a dynamically transversely trapping surface (DTTS) and a marginally DTTS, as indicators for a strong gravity region. A DTTS is defined as a two-dimensional…
Extension of photon surfaces and their area: Static and stationary spacetimes
Hirotaka Yoshino, Keisuke Izumi, Tetsuya Shiromizu +1
We propose a new concept, the transversely trapping surface (TTS), as an extension of the static photon surface characterizing the strong gravity region of a static/stationary spac…
Area bound for a surface in a strong gravity region
Tetsuya Shiromizu, Yoshimune Tomikawa, Keisuke Izumi +1
For asymptotically flat spacetimes, using the inverse mean curvature flow, we show that any compact -surface, , whose mean curvature and its derivative for outward directio…
On uniqueness of static spacetimes with non-trivial conformal scalar field
Yoshimune Tomikawa, Tetsuya Shiromizu, Keisuke Izumi
We discuss the uniqueness of the static spacetimes with non-trivial conformal scalar field. Then, we can show that the spacetime is unique to be the Bocharova-Bronnikov-Melnikov-Be…
On uniqueness of static black hole with conformal scalar hair
Yoshimune Tomikawa, Tetsuya Shiromizu, Keisuke Izumi
We discuss the uniqueness of the static black hole in the Einstein gravity with a conformally coupled scalar field. In particular, we prove the uniqueness of the region outside of…
New definition of wormhole throat
Yoshimune Tomikawa, Keisuke Izumi, Tetsuya Shiromizu
We present a new definition of the wormhole throat including the flare-out condition and the traversability for general dynamical spacetimes in terms of null geodesic congruences.…
Wormhole on DGP brane
Yoshimune Tomikawa, Tetsuya Shiromizu, Keisuke Izumi
We analyze a spacetime structure on a new brane configuration constructed recently in the Dvali-Gabadadze-Porrati braneworld context. The brane, embedded on a five-dimensional bubb…