We consider string theory in the background of the two-dimensional black hole as described by the SL(2, R)/U(1) coset theory recently introduced by Witten. We study the spectrum of this conformal… (More)

In this note we prove an identity that equates the elliptic genus partition function of a supersymmetric sigma model on the N -fold symmetric product M/SN of a manifoldM to the partition function of… (More)

We propose a direct correspondence between the classical evolution equations of 5-d supergravity and the renormalization group (RG) equations of the dual 4-d large N gauge theory. Using standard… (More)

The holographic principle is studied in the context of a n + 1 dimensional radiation dominated closed Friedman-Robertson-Walker (FRW) universe. The radiation is represented by a conformal field… (More)

We argue that the topological string partition function, which has been known to correspond to a wave-function, can be interpreted as an exact “wave-function of the universe” in the mini-superspace… (More)

The dyonic 1/4-BPS states in 4D string theory with N = 4 spacetime supersymmetry are counted by a Siegel modular form. The pole structure of the modular form leads to a contour dependence in the… (More)

The light-like linear dilaton background represents a particularly simple timedependent 1/2 BPS solution of critical type IIA superstring theory in ten dimensions. Its lift to M-theory, as well as… (More)

We derive an exact expression for the Fourier coefficients of elliptic genera on Calabi-Yau manifolds which is well-suited to studying the AdS/CFT correspondence on AdS3 × S. The expression also… (More)

We give a derivation of the loop equation for two-dimensional gravity from the KdV equations and the string equation of the one matrix model. We find that the loop equation is equivalent to an… (More)

We investigate Penrose limits of two classes of non-local theories, little string theories and non-commutative gauge theories. Penrose limits of the near-horizon geometry of NS5-branes help to shed… (More)