相关论文: String--Kaluza--Klein Cosmology

The dynamics of a string near a Kaluza-Klein black hole are studied. Solutions to the classical string equations of motion are obtained using the world sheet velocity of light as an expansion parameter. The electrically and magnetically…

We provide a new five dimensional black string--like solution by means of the embedding of a four dimensional regular black hole into a compact extra dimension. We enunciate a list of constraints in order to that the five dimensional black…

Singularity-free cosmological solutions may be obtained from the string action at tree level if the dimension of the space-time is greater than 10 and if brane configurations are taken into account. The behaviour of the dilaton field in…

We study charged black hole solutions in Einstein-Gauss-Bonnet theory with the dilaton field which is the low-energy effective theory of the heterotic string. The spacetime is D-dimensional and assumed to be static and spherically symmetric…

This brief report presents analytical solutions to the equations of motion of a null string. The background spacetime is a magnetically charged Kaluza-Klein black hole. The string coordinates are expanded with the world-sheet velocity of…

We study black hole solutions in the Einstein gravity with Gauss-Bonnet term, the dilaton and a positive "cosmological constant" in various dimensions. Physically meaningful black holes with a positive cosmological term are obtained only…

We examine an exact solution which represents a charged black hole in a Kaluza-Klein universe in the five-dimensional Einstein-Maxwell theory. The spacetime approaches to the five-dimensional Kasner solution that describes expanding three…

We study spherically symmetric, asymptotically flat black hole solutions in the low-energy effective heterotic string theory, which is the Einstein gravity with Gauss-Bonnet term and the dilaton, in various dimensions. We derive the field…

We present a review of black holes and black string solutions available in the $d$-dimensional Einstein and Einstein-Maxwell model in the presence of a cosmological constant. Due to the cosmological constant, the equations do not admit…

We determine the different possible space-time metrics inside an infinite rotating hollow cylinder with given energy density and longitudinal and azimuthal stresses, the metric outside the cylinder being chosen of the spinning cosmic string…

We derive and study a class of cosmological and wormhole solutions of low-energy effective string field theory. We consider a general four-dimensional string effective action where moduli of the compactified manifold and the electromagnetic…

We consider a class of extremal and non-extremal four-dimensional black-hole solutions occuring in toroidally compactified heterotic string theory, whose ten-dimensional interpretation involves a Kaluza-Klein monopole and a five-brane. We…

We generalize the vacuum static black strings with negative cosmological constant recently discussed in literature, by including an electromagnetic field. These higher-dimensional configurations have no dependence on the `compact' extra…

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,…

We investigate thermodynamical properties of four and five dimensional black hole solutions of toroidally compactified string theory. We derive an analog of Smarr's formula and verify it directly using the metric.

We study configurations consisting of a pair of non-extremal black holes in four dimensions, both with the same mass, and with charges of the same magnitude but opposite sign---diholes, for short. We present such exact solutions for…

We consider the third order Lovelock equations without the cosmological constant term in an empty $n(\geq 8)$-dimensional Kaluza-Klein spacetime $\mathcal{M}^{4}\times \mathcal{K}^{n-4}$, where $\mathcal{K}^{n-4}$ is a constant curvature…

An internal singularity of a string four-dimensional black hole with second order curvature corrections is discussed. A restriction to a minimal size of a neutral black hole is obtained in the frame of the model considered. Vacuum…

We present a new expression for the five-dimensional static Kaluza-Klein black hole solution with squashed $S^3$ horizons and three different charge parameters. This black hole solution belongs to $D = 5$ $N = 2$ supergravity theory, its…

We calculate dimensional reduction of gravitational flux tube solutions in the scheme of Kaluza-Klein theory. The fifth dimension is compacified to a region of Planck size. Assuming the width of the tube to be also Planck size we obtain…