Exact Black String Solutions in Three Dimensions

A black hole solution to three dimensional general relativity with a negative cosmological constant has recently been found. We show that a slight modification of this solution yields an exact solution to string theory. This black hole is equivalent (under duality) to the previously discussed three dimensional black string solution. Since the black string is asymptotically flat and the black hole is asymptotically anti-de Sitter, this suggests that strings are not affected by...

Considering cylindrical topology we present the static solution for a charged black hole in conformal gravity. We show that unlike the general relativistic case there are two different solutions, both including a factor that when set to zero recovers the familiar static charged black string solution in Einstein's theory. This factor gives rise to a linear term in the potential that also features in the neutral case and may have significant ramifications for particle trajector...

Solutions to low energy string theory describing black holes and black strings are reviewed. Many of these solutions can be obtained by applying simple solution generating transformations to the Schwarzschild metric. In a few cases, the corresponding exact conformal field theory is known. Various properties of these solutions are discussed including their global structure, singularities, and Hawking temperature. (This review is based on lectures given at the 1992 Trieste Spri...

We construct an exact CFT as an SL(2,R)xSU(2)/U(1)^2 gauged WZW model, which describes a black hole in 4 dimensions. Another exact solution, describing a black membrane in 4D (in the sense that the event horizon is an infinite plane) is found as an SL(2,R)xU(1)^2/U(1) gauged WZW model. Finally, we construct an exact solution of a 4D black hole with electromagnetic field, as an SL(2,R)xSU(2)xU(1)/U(1)^2 gauged WZW model. This black hole carries both electric and axionic charge...

We present two different families of stationary black strings in three dimensions carrying electric and axion charges. Both solutions contain a singular region, which however is quite harmless for string frame geodesic observers, because the solutions are causally geodesically complete. In addition, we exhibit a variety of extremal limits of our solutions, and argue that there must exist a more general family continuously interpolating between them.

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 the inverse string tension, and hence represent exact conformal field theories on the world-sheet. Furthermore, since the dilaton for these two solutions is constant, they also solve the equations of motion of standard GR with a minimally cou...

In this review article we describe some of the recent progress towards the construction and analysis of three-charge configurations in string theory and supergravity. We begin by describing the Born-Infeld construction of three-charge supertubes with two dipole charges, and then discuss the general method of constructing three-charge solutions in five dimensions. We explain in detail the use of these methods to construct black rings, black holes, as well as smooth microstate ...

We review some recent results about exact classical solutions in string theory. In particular, we consider four dimensional extremal electric black holes which are related via dimensional reduction to the exact five dimensional fundamental string solutions. We also comment on the issue of \a' corrections to non-extremal black holes. (To appear in Proceedings of the Conference on Current Topics in Astrofundamental Physics, September 1994, Erice)

Static spherically symmetric asymptotically flat charged black hole solutions are constructed within the magnetic SU(3) sector of the 4-dimensional heterotic string effective action. They possess non-abelian hair in addition to the Coulomb magnetic field and are qualitatively similar to the Einstein-Yang-Mills colored SU(3) black holes except for the extremal case. In the extremality limit the horizon shrinks and the resulting geometry around the origin coincides with that of...

We show that the leading order solution describing an extremal electrically charged black hole in string theory is, in fact, an exact solution to all orders in $\a'$ when interpreted in a Kaluza-Klein fashion. This follows from the observation that it can be obtained via dimensional reduction from a five dimensional background which is proved to be an exact string solution.