Shinya Tomizawa

Topology Changing Process of Coalescing Black Holes on Eguchi-Hanson Space (2009)

Kimura, Masashi, Ishihara, Hideki, Tomizawa, Shinya, Yoo, Chul-Moon

We numerically study the event horizons of two kinds of five-dimensional coalescing black hole solutions with different asymptotic structures: the five-dimensional Kastor-Traschen solution (5DKT) and...

Coset for Hopf fibration and Squashing (2009)

Hatsuda, Machiko, Tomizawa, Shinya

We provide a simple derivation of metrics for fundamental geometrical deformations such as Hopf fibration, squashing and Z_k quotient which play essential roles in recent studies on the AdS4/CFT3. A...

A uniqueness theorem for charged rotating black holes in five-dimensional minimal supergravity (2009)

Tomizawa, Shinya, Yasui, Yukinori, Ishibashi, Akihiro

We show a uniqueness theorem for charged rotating black holes in the bosonic sector of five-dimensional minimal supergravity. More precisely, under the assumptions of the existence of two commuting...

Charged Rotating Kaluza-Klein Black Holes Generated by G2(2) Transformation (2008)

Tomizawa, Shinya, Yasui, Yukinori, Morisawa, Yoshiyuki

Applying the G_{2(2)} generating technique for minimal D=5 supergravity to the Rasheed black hole solution, we present a new rotating charged Kaluza-Klein black hole solution to the five-dimensional...

Charged Black Holes in a Rotating Gross-Perry-Sorkin Monopole Background (2008)

Tomizawa, Shinya, Ishibashi, Akihiro

We present a new class of stationary charged black hole solutions to five-dimensional Einstein-Maxwell-Chern-Simons theories. We construct the solutions by utilizing so called the squashing...

Rotating Kaluza-Klein Multi-Black Holes with Godel Parameter (2008)

Matsuno, Ken, Ishihara, Hideki, Nakagawa, Toshiharu, Tomizawa, Shinya

We obtain new five-dimensional supersymmetric rotating multi-Kaluza-Klein black hole solutions with the Godel parameter in the Einstein-Maxwell system with a Chern-Simons term. These solutions have...

Squashed Kerr-Godel Black Holes - Kaluza-Klein Black Holes with Rotations of Black Hole and Universe - (2008)

Tomizawa, Shinya, Ishihara, Hideki, Matsuno, Ken, Nakagawa, Toshiharu

Applying squashing transformation to Kerr-Godel black hole solutions, we present a new type of a rotating Kaluza-Klein black hole solution to the five-dimensional Einstein-Maxwell theory with a...

Multi-Black Rings on Eguchi-Hanson Space (2008)

Tomizawa, Shinya

We construct new supersymmetric multi-black ring solutions on the Eguchi-Hanson base space as solutions of the five-dimensional minimal supergravity. The space-time has an asymptotically locally...

Charged Rotating Kaluza-Klein Black Holes in Five Dimensions (2007)

Nakagawa, Toshiharu, Ishihara, Hideki, Matsuno, Ken, Tomizawa, Shinya

We construct a new charged rotating Kaluza-Klein black hole solution in the five-dimensional Einstein-Maxwell theory with a Chern-Simon term. The features of the solutions are also investigated. The...

Boundary Value Problem for Black Rings (2007)

Morisawa, Yoshiyuki, Tomizawa, Shinya, Yasui, Yukinori

We study the boundary value problem for asymptotically flat stationary black ring solutions to the five-dimensional vacuum Einstein equations. Assuming the existence of two additional commuting axial...

Horizons of Coalescing Black Holes on Eguchi-Hanson Space (2007)

Yoo, Chul-Moon, Ishihara, Hideki, Kimura, Masashi, Matsuno, Ken, Tomizawa, Shinya

Using the numerical method, we study dynamics of coalescing black holes on the Eguchi-Hanson base space. Effects of a difference in spacetime topology on the black hole dynamics is discussed. We...

Coalescence of Rotating Black Holes on Eguchi-Hanson Space (2007)

Matsuno, Ken, Ishihara, Hideki, Kimura, Masashi, Tomizawa, Shinya

We obtain new charged rotating multi-black hole solutions on the Eguchi-Hanson space in the five-dimensional Einstein-Maxwell system with a Chern-Simons term and a positive cosmological constant. In...

Boosted Black Holes on Kaluza-Klein Bubbles (2007)

Iguchi, Hideo, Mishima, Takashi, Tomizawa, Shinya

We construct an exact stationary solution of black hole -- bubble sequence in the five dimensional Kaluza-Klein theory by using solitonic solution generating techniques. The solution describes two...

Supersymmetric Black Rings on Eguchi-Hanson Space (2007)

Tomizawa, Shinya, Ishihara, Hideki, Kimura, Masashi, Matsuno, Ken

We construct new supersymmetric black ring solutions on the Eguchi-Hanson base space as solutions of five-dimensional minimal supergravity. The solutions have the same two angular momentum components...

Rotating Black Holes on Kaluza-Klein Bubbles (2007)

Tomizawa, Shinya, Iguchi, Hideo, Mishima, Takashi

Using the solitonic solution generating techniques, we generate a new exact solution which describes a pair of rotating black holes on a Kaluza-Klein bubble as a vacuum solution in the...

Cosmological Black Holes on Taub-NUT space in Five-Dimensional Einstein-Maxwell Theory (2007)

Ida, Daisuke, Ishihara, Hideki, Kimura, Masashi, Matsuno, Ken, Morisawa, Yoshiyuki, Tomizawa, Shinya

The cosmological black hole solution on the Gibbons-Hawking space has been constructed. We also investigate the properties of this solution in the case of a single black hole. Unlike the...

Topology Change of Coalescing Black Holes on Eguchi-Hanson Space (2006)

Ishihara, Hideki, Kimura, Masashi, Tomizawa, Shinya

We construct multi-black hole solutions in the five-dimensional Einstein-Maxwell theory with a positive cosmological constant on the Eguchi-Hanson space, which is an asymptotically locally Euclidean...

Relationship Between Solitonic Solutions of Five-Dimensional Einstein Equations (2006)

Tomizawa, Shinya, Iguchi, Hideo, Mishima, Takashi

We give the relation between the solutions generated by the inverse scattering method and the B\"acklund transformation applied to the vacuum five-dimensional Einstein equations. In particular, we...

Black Holes on Eguchi-Hanson Space in Five-Dimensional Einstein-Maxwell Theory (2006)

Ishihara, Hideki, Kimura, Masashi, Matsuno, Ken, Tomizawa, Shinya

We construct a pair of black holes on the Eguchi-Hanson space as a solution in the five-dimensional Einstein-Maxwell theory.

Kaluza-Klein Multi-Black Holes in Five-Dimensional Einstein-Maxwell Theory (2006)

Ishihara, Hideki, Kimura, Masashi, Matsuno, Ken, Tomizawa, Shinya

We construct the Kaluza-Klein multi-black hole solutions on the Gibbons-Hawking multi-instanton space in the five-dimensional Einstein-Maxwell theory. We study geometric properties of the multi-black...

Vaccum solutions of five-dimensional Einstein equations generated by inverse scattering method II : Production of black ring solution (2006)

Tomizawa, Shinya, Nozawa, Masato

We study vacuum solutions of five-dimensional Einstein equations generated by the inverse scattering method. We reproduce the black ring solution which was found by Emparan and Reall by taking the...

Vacuum solutions of five dimensional Einstein equations generated by inverse scattering method (2005)

Tomizawa, Shinya, Morisawa, Yoshiyuki, Yasui, Yukinori

We study stationary and axially symmetric two solitonic solutions of five dimensional vacuum Einstein equations by using the inverse scattering method developed by Belinski and Zakharov. In this...

Energy density bounds for black strings (2005)

Tomizawa, Shinya

The conserved charge called Y-ADM mass density associated with asymptotically translational Killing-Yano tensor gives us an appropriate physical meaning about the energy density of $p$ brane...

Limit structure of Future Null Infinity tangent -topology of the event horizon and gravitational wave tail- (2005)

Tomizawa, Shinya, Siino, Masaru

We investigated the relation between the behavior of gravitational wave at late time and the limit structure of future null infinity tangent which will determine the topology of the event horizon far...

Positivity Bounds for the Y-ADM Mass Density (2004)

Kastor, David, Shiromizu, Tetsuya, Tomizawa, Shinya, Traschen, Jennie

Killing-Yano tensors are natural generalizations of Killing vectors to arbitrary rank anti-symmetric tensor fields. It was recently shown that Killing-Yano tensors lead to conserved gravitational...

Kaluza-Klein bubble like structure and celestial sphere in inflationary universe (2004)

Shiromizu, Tetsuya, Tomizawa, Shinya, Uchida, Yuki, Mukohyama, Shinji

We consider five dimensional deSitter spacetimes with a deficit angle due to the presence of a closed 2-brane and identify one dimension as an extra dimension. From the four dimensional viewpoint we...

Twist of stationary black hole/ring in five dimensions (2004)

Tomizawa, Shinya, Uchida, Yuki, Shiromizu, Tetsuya

It is unlikely that uniqueness theorem holds for stationary black holes in higher dimensional spacetimes. However, we will examine the possibility that the higher multipole moments classify vacuum...

Spatial infinity in higher dimensional spacetimes (2004)

Shiromizu, Tetsuya, Tomizawa, Shinya

Motivated by recent studies on the uniqueness or non-uniqueness of higher dimensional black hole spacetime, we investigate the asymptotic structure of spatial infinity in n-dimensional spacetimes($n...

Kinematical bound in asymptotically translationally invariant spacetimes (2003)

Shiromizu, Tetsuya, Ida, Daisuke, Tomizawa, Shinya

We present positive energy theorems in asymptotically translationally invariant spacetimes which can be applicable to black strings and charged branes. We also address the bound property of the...