相关论文: Multidimensional Sigma-Model with Black Holes and …

A multidimensional gravitational model containing scalar fields and antisymmetric forms is considered. The manifold is chosen in the form M = M_0 x M_1 x ... x M_n, where M_i are Einstein spaces (i > 0). The sigma-model approach and exact…

Starting with the D-dimensional Einstein-dilaton-antisymmetric form equations and assuming a block-diagonal form of a metric we derive a $(D-d)$-dimensional $\sigma$-model with the target space $SL(d,R)/SO(d) \times SL(2,R)/SO(2) \times R$…

Two solutions of stringy gravity in three and four dimensions which admit interpretation as a black hole and a black string, respectively, are discussed. It is demonstrated that they are exact WZWN nonlinear sigma models to all orders in…

We discuss the worldsheet sigma-model whose target space is the $d+1$ dimensional Euclidean Schwarzschild black hole. We argue that in the limit where the Hawking temperature of the black hole, $T$, approaches the Hagedorn temperature,…

The Lorentz harmonic formulation of D-dimensional bosonic p-brane theory with $D\geq (p+1)(p+2)/2$ coupled to an antisymmetric tensor field of rank d=(p+1) provides the dynamical ground for the description of d=(p+1) dimensional Gravity. It…

The properties of the effective sigma-model for D-dimensional Einstein gravity based on multidimensional geometries is analyzed. Besides pure geometry, additional minimally coupled scalars and (p+2)-forms are considered which yield an…

We construct new configurations of oppositely charged, static black hole pairs (diholes) in four dimensions which are solutions of low energy string/M-theory. The black holes are extremal and have four different charges. We also consider…

Black hole generalized p-brane solutions for a wide class of intersection rules are presented. The solutions are defined on a manifold that contains a product of n - 1 Ricci-flat internal spaces. They are defined up to moduli functions H_s…

We point out that in the limit of large number of dimensions a wide class of non-extremal neutral black holes has a universal near horizon limit. The limiting geometry is the two-dimensional black hole of string theory with a…

We study intersecting D-branes in type 0 string theories and show that the D$p_{\pm}$-brane bound states obey similar intersecting rules as the D$p$-branes of the type II theories. The D$5_{\pm}$-D$1_{\pm}$ brane system is studied in…

We obtain a generalized Schwarzschild (GS-) and a generalized Reissner-Nordstrom (GRN-) black hole geometries in (3+1)-dimensions, in a noncommutative string theory. In particular, we consider an effective theory of gravity on a curved…

We study O($N+1$) nonlinear $\sigma$-model in $(p+1+N)$-dimensional curved spacetime with negative cosmological constant, and find a new $\sigma$-lump solution with half-integer winding and divergent energy. When the spatial structure of…

We explore the interplay between black holes in supergravity and quantum field theories on the world-volumes of D-branes. A brief summary of black hole entropy calculations for D-brane black holes is followed by a detailed study of particle…

We study D-branes of N=2 supersymmetric sigma models. Supersymmetric nonlinear sigma models with 2-dimensional target space have D0,D1,D2-branes, which are realized as A-,B-type supersymmetric boundary conditions on the worldsheet. When we…

We present a new set of analytic solutions of general relativity with a negative cosmological constant, which describe black strings and black p-branes in arbitrary number of dimensions, $D$. The solutions are supported by minimally…

We analyze p-brane black hole solutions with `block-orthogonal' intersection rules. The post-Newtonian parameters beta and gamma corresponding to 4-dimensional section of the metric are calculated. A family of solutions with gamma=1 is…

A general class of solutions of string background equations is studied and its physical interpretations are presented. These solutions correspond to generalizations of the standard black p-brane solutions to surfaces with curvature k=-1,0.…

We develop the effective worldvolume theory for the dynamics of black branes with charges of the kind that arise in many supergravities and low-energy limits of string theory. Using this theory, we construct numerous new rotating black…

The supersymmetry arises in certain theories of fermions coupled to gauge fields and gravity in a spacetime of 11 dimensions. The dynamical brane background has mainly been studied for the class of purely bosonic solutions only, but recent…

Classical gravitating field theories reduced to three dimensions admit manifest gauge invariances and hidden symmetries, which together make up the invariance group G of the theory. If this group is large enough, the target space is a…