Daisuke Ida

Brane world cosmology

A simple model of the brane-world cosmology has been proposed, which is characterized by four parameters, namely, the bulk cosmological constant, the spatial curvature of the universe, the radiation strength arising from bulk space-time and the breaking parameter of 2-symmetry. The bulk space-time is assumed to be locally static five-dimensional analogue of the Schwarzschild-Anti-de Sitter space-time, and then the location of three-brane is determined by the metric junction. The resulting Friedmann equation recovers the standard cosmology, and a new term arises if 2-symmetry is not assumed, which behaves as a cosmological term in the early universe, next turns to a negative curvature term, and finally damps rapidly.

Uniqueness and non-uniqueness of static vacuum black holes in higher dimensions

We prove a uniqueness theorem for asymptotically flat static charged dilaton black hole solutions in higher dimensional space-times. We also construct infinitely many non-asymptotically flat regular static black holes on the same space-time manifold with the same spherical topology. An application to the uniqueness of a certain class of flat

Uniqueness and nonuniqueness of static black holes in higher dimensions.

p

Gravitational energy, dS / CFT correspondence and cosmic no hair

-branes is also given.

Uniqueness of (dilatonic) charged black holes and black p-branes in higher dimensions

We prove a uniqueness theorem for asymptotically flat static charged dilaton black-hole solutions in higher-dimensional space-times. We also construct infinitely many nonasymptotically flat regular static black holes on the same space-time manifold with the same spherical topology. An application to the uniqueness of a class of flat p-branes is also given.

Rotating black holes at future colliders. II. Anisotropic scalar field emission

The gravitational energy is examined in asymptotically de Sitter space-times. The positivity will be shown for certain cases. The de Sitter/CFT(dS/CFT) correspondence recently proposed and cosmic no-hair conjecture are testified in the aspect of the gravitational energy. From the holographic renormalization group point of view, the two conjectures are deeply connected with each other.

No black-hole theorem in three-dimensional gravity

We prove the uniqueness of higher dimensional (dilatonic) charged black holes in static and asymptotically flat spacetimes for arbitrary vector-dilaton coupling constant. An application to the uniqueness of a wide class of black p-branes is also given.

Boundary value problem for five-dimensional stationary rotating black holes

This is the sequel to the first paper of the series, where we have discussed the Hawking radiation from five-dimensional rotating black holes for spin 0, 1/2, and 1 brane fields in the low frequency regime. We consider the emission of a brane-localized scalar field from rotating black holes in general space-time dimensions without relying on the low frequency expansions.

Brane-World and Holography

A common property of known black-hole solutions in (2+1)-dimensional gravity is that they require a negative cosmological constant. To explain this, it is shown in this Letter that a (2+1)-dimensional gravity theory which satisfies the dominant energy condition forbids the existence of a black hole.

Anti-de Sitter no hair, AdS / CFT and the brane world

We study the boundary value problem for stationary rotating black hole solutions to the five-dimensional vacuum Einstein equation. Assuming the existence of two additional commuting rotational Killing vector fields and sphericity of the horizon topology, we show that a black hole with a regular event horizon is uniquely characterized by its mass and a pair of angular momenta.