50 citations · 541 across the 47 of their papers we have counts for
13 papers · 1 filter
Stable circular orbits in Kaluza-Klein black hole spacetimes
Shinya Tomizawa, Takahisa Igata
Reducing motion of particles to a two-dimensional potential problem, we show that there are stable circular orbits around a squashed Kaluza-Klein black hole with a spherical horizo…
Stable bound orbits in black lens backgrounds
Shinya Tomizawa, Takahisa Igata
In contrast to five-dimensional Schwarzschild-Tangherlini and Myers-Perry backgrounds, we show that there are stable bound orbits of massive/massless particles in five-dimensional…
Stable circular orbits in higher-dimensional multi-black hole spacetimes
Takahisa Igata, Shinya Tomizawa
We consider the dynamics of particles, particularly focusing on circular orbits in the higher-dimensional Majumdar-Papapetrou (MP) spacetimes with two equal mass black holes. It is…
Stable bound orbits around a supersymmetric black lens
Shinya Tomizawa, Takahisa Igata
In higher-dimensional Schwarzschild black hole spacetimes, there are no stable bound orbits of particles. In contrast to this, it is shown that there are stable bound orbits in a f…
Scale invariance and constants of motion
Takahisa Igata
Scale invariance in the theory of classical mechanics can be induced from the scale invariance of background fields. In this paper we consider the relation between the scale invari…
Integrability of Particle System around a Ring Source as the Newtonian Limit of a Black Ring
Takahisa Igata, Hideki Ishihara, Hirotaka Yoshino
The geodesic equation in the five-dimensional singly rotating black ring is non-integrable unlike the case of the Myers-Perry black hole. In the Newtonian limit of the black ring,…
Stable Bound Orbits of Massless Particles around a Black Ring
Takahisa Igata, Hideki Ishihara, Yohsuke Takamori
We study the geodesic motion of massless particles in singly rotating black ring spacetimes. We find stable stationary orbits of massless particles in toroidal spiral shape in the…
Stationary Closed Strings in Five-dimensional Flat Spacetime
Takahisa Igata, Hideki Ishihara, Keisuke Nishiwaki
We investigate stationary rotating closed Nambu-Goto strings in five-dimensional flat spacetime. The stationary string is defined as a worldsheet that is tangent to a timelike Kill…
Chaos in Geodesic Motion around a Black Ring
Takahisa Igata, Hideki Ishihara, Yohsuke Takamori
We study bound orbits of a free particle around a singly rotating black ring. We find there exists chaotic motion of a particle which is gravitationally bound to the black ring by…
Stable Bound Orbits around Black Rings
Takahisa Igata, Hideki Ishihara, Yohsuke Takamori
We examine bound orbits of particles around singly rotating black rings. We show that there exist stable bound orbits in toroidal spiral shape near the axis of the ring, and also e…
Toroidal Spiral Strings in Higher-dimensional Spacetime
Takahisa Igata, Hideki Ishihara
We report on our progress in research of separability of the Nambu-Goto equation for test strings with a symmetric configuration in a shape of toroidal spiral in a five-dimensional…
Dynamics of Toroidal Spiral Strings around Five-dimensional Black Holes
Takahisa Igata, Hideki Ishihara
We examine the separability of the Nambu-Goto equation for test strings in a shape of toroidal spiral in a five-dimensional Kerr-AdS black hole. In particular, for a `{\it Hopf loo…
Toroidal Spiral Nambu-Goto Strings around Higher-Dimensional Black Holes
Takahisa Igata, Hideki Ishihara
We present solutions of the Nambu-Goto equation for test strings in a shape of toroidal spiral in five-dimensional spacetimes. In particular, we show that stationary toroidal spira…