相关论文: An Equivalence Between Momentum and Charge in Stri…

The past year has seen enormous progress in string theory. It has become clear that all of the different string theories are different limits of a single theory. Moreover, in certain limits, one obtains a new, eleven-dimensional structure…

We examine the two-dimensional spacetimes that emerge from string theory. We find all the solutions with no tachyons, and show that the only non-trivial solution is the black hole spacetime. We examine the role of duality in this picture.…

We investigate the qualitative new features of charged dilatonic black holes which emerge when both the Yang-Mills and Gauss-Bonnet curvature corrections are included in the effective action. We consider perturbative effects by an expansion…

In addition to the boosted static solution there are two other classes of stationary string-like solutions of the vacuum Einstein equation in (4+1)-dimensions. Each class is characterized by three parameters of mass, tension, and momentum…

We construct a solution of the classical equations of motion arising in the low energy effective field theory for heterotic string theory. This solution describes a black hole in four dimensions carrying mass $M$, charge $Q$ and angular…

The motion of a string in curved spacetime is discussed in detail. The basic formalism for string motion in Minkowski spacetime and in curved spacetime is presented. The description applies to cosmic strings as well as to fundamental…

I discuss various aspects of background independence in the context of string theory, for which so far we have no manifestly background independent formulation. After reviewing the role of background independence in classical Einstein…

While in string theory the subject of sources in imaginary time has received some attention, we demonstrate the power of imaginary sources by proving that they constitute in several field theories a complete basis for all smooth and time…

The specific model studied is in the context of the modified measure formulation the string or branes where tension appear as an additional dynamical degree of freedom . We then consider the signed reparametrization invariant volume element…

We explore via linearized perturbation theory the Gregory-Laflamme instability of rotating black strings with equal magnitude angular momenta. Our results indicate that the Gregory-Laflamme instability persists up to extremality for all…

We consider black-string-type solutions in five-dimensional Einstein-Gauss-Bonnet gravity. Numerically constructed solutions under static, axially symmetric and translationally invariant metric ansatz are presented. The solutions are…

String theory on 2-d charged black holes corresponding to (SL(2)xU(1)_L)/U(1) exact asymmetric quotient CFTs are investigated. These backgrounds can be embedded, in particular, in a two dimensional heterotic string. In the extremal case,…

We consider string theory in a time dependent orbifold with a null singularity. The singularity separates a contracting universe from an expanding universe, thus constituting a big crunch followed by a big bang. We quantize the theory both…

Some shortcomings in regard to our lack of conceptual understanding of string theory are displayed and prescription to untangle them is proposed. String theory should be a fundamental dynamics of four dimensional symmetric space-times.…

If string theory describes nature, then charged black holes are not described by the Reissner-Nordstrom solution. This solution must be modified to include a massive dilaton. In the limit of vanishing dilaton mass, the new solution can be…

The aim of this paper is to use correspondence between solutions in the $c=1$ matrix model collective field theory and coupled dilaton-gravity to a massless scalar field. First, we obtain the incoming and outgoing fluctuations for the…

Non-uniform black strings coupled to a gauge field are constructed by a perturbative method in a wide range of spacetime dimensions. At the linear order of perturbations, we see that the Gregory-Laflamme instability vanishes at the point…

This is a very brief survey of some results in the geometry of string duality delivered at a lecture given at ICM 1998, Berlin. String Duality is the statement that one kind of string theory compactified on one space is equivalent in some…

We prove that a large class of leading order string solutions which generalize both the plane-wave and fundamental string backgrounds are, in fact, exact solutions to all orders in \alpha'. These include, in particular, the traveling waves…

We study aspects of d-dimensional black holes with two electric charges, corresponding to fundamental strings with generic momentum and winding on an internal circle. The perturbative alpha' corrections to such black holes and their…