Shinya Tomizawa

Uniqueness theorem for charged rotating black holes in five-dimensional minimal supergravity

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 axial isometries and spherical topology of horizon cross sections, we prove that an asymptotically flat, stationary charged rotating black hole with finite temperature in the five-dimensional Einstein-Maxwell-Chern-Simons theory is uniquely characterized by the mass, charge, and two independent angular momenta and therefore is described by the Chong-Cvetic-Lue-Pope solution. We also discuss a generalization of our uniqueness theorem for spherical black holes to the case of black rings.

Charged rotating Kaluza-Klein black holes in five dimensions

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 spacetime is asymptotically locally flat, i.e., it asymptotes to a twisted S{sup 1} bundle over the four-dimensional Minkowski spacetime. The solution describe a non-BPS black hole rotating in the direction of the extra dimension. The solutions have the limits to the supersymmetric black hole solutions, a new extreme non-BPS black hole solution and a new rotating non-BPS black hole solution with a constant twisted S{sup 1} fiber.

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

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 generation of the solutions, we use five dimensional Minkowski spacetime as a seed. It is shown that if we restrict ourselves to the case of one angular momentum component, the generated solution coincides with a black ring solution with a rotating two sphere which was found by Mishima and Iguchi recently.

Vacuum solutions of five dimensional Einstein equations generated by inverse scattering method. II. Production of the black ring solution

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 Euclidean Levi-Civita metric plus one-dimensional flat space as a seed. This transformation consists of two successive processes; the first step is to perform the three-solitonic transformation of the Euclidean Levi-Civita metric with one-dimensional flat space as a seed. The resulting metric is the Euclidean C-metric with extra one-dimensional flat space. The second is to perform the two-solitonic transformation by taking it as a new seed. Our result may serve as a stepping stone to find new exact solutions in higher dimensions.

Kaluza-Klein multi-black holes in five-dimensional Einstein-Maxwell theory

We construct Kaluza–Klein multi-black hole solutions on the Gibbons–Hawking multi-instanton space in the five-dimensional Einstein–Maxwell theory. We study the geometric properties of the multi-black hole solutions. In particular, unlike the Gibbons–Hawking multi-instanton solutions, each nut-charge is able to take a different value due to the existence of a black hole on it. The spatial cross section of each horizon is admitted to have the topology of a different lens space in addition to S3.

Kaluza-Klein-Kerr-Godel Black Holes Kaluza-Klein Black Holes with Rotations of Black Hole and Universe

Applying squashing transformation to the Kerr-Godel black hole solution, we present a new type of a rotating Kaluza-Klein black hole solution in the five-dimensional minimal supergravity. The new solution generated by the squashing transformation has no closed timelike curve outside the black hole horizons. The spacetime is asymptotically locally flat. One of the remarkable features is that the solution has two independent rotation parameters along an extra dimension associated with the black holes rotation and Godels rotation. The spacetime also admits the existence of two disconnected ergoregions, an inner ergoregion and an outer ergoregion. These two ergoregions can rotate in opposite directions as well as in the same direction. Subject Index: 450, 451

Rotating Kaluza-Klein multi-black holes with Gödel parameter

We obtain new five-dimensional supersymmetric rotating multi-Kaluza-Klein black hole solutions with the Goedel parameter in the Einstein-Maxwell system with a Chern-Simons term. These solutions have no closed timelike curve outside the black hole horizons. At infinity, the space-time is effectively four-dimensional. Each horizon admits various lens space topologies L(n;1)=S{sup 3}/Z{sub n} in addition to a round S{sup 3}. The space-time can have outer ergoregions disjointed from the black hole horizons, as well as inner ergoregions attached to each horizon. We discuss the rich structures of ergoregions.

Black holes on Eguchi-Hanson space in five-dimensional Einstein-Maxwell theory

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

Kinematical bound in asymptotically translationally invariant space-times

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

Uniqueness theorem for charged dipole rings in five-dimensional minimal supergravity

We show a uniqueness theorem for charged dipole rotating black rings in the bosonic sector of five-dimensional minimal supergravity, generalizing our previous work [arXiv:0901.4724] on the uniqueness of charged rotating black holes with topologically spherical horizon in the same theory. More precisely, assuming the existence of two commuting axial Killing vector fields and the same rod structure as the known solutions, we prove that an asymptotically flat, stationary charged rotating black hole with nondegenerate connected event horizon of cross-section topology