This paper is devoted to recent progress made towards the understanding of closed bosonic
and fermionic string perturbation theory, formulated in a Lorentz-covariant way on Euclidean …

We review recent developments in the construction of heterotic and type II string field
theories and their various applications. These include systematic procedures for determining …

These lectures consisted of an elementary introduction to conformal field theory, with some
applications to statistical mechanical systems, and fewer to string theory. Contents: 1 …

We consider toy models of holography arising from 3d Chern-Simons theory. In this context
a duality to an ensemble average over 2d CFTs has been recently proposed. We put forward …

We study the theory of c= 1 torus and ℤ 2-orbifold models on general Riemann surfaces.
The operator content and occurrence of multi-critical points in this class of theories is …

We show that certain type II string amplitudes at genus g are given by the topological
partition function F g discussed recently by Bershadsky, Cecotti, Ooguri and Vafa. These …

Recurrent relations for orthogonal polynomials, arising in the study of the one-matrix model
of two-dimensional gravity, are shown to be equivalent to the equations of the Toda-chain …

The goal of these lectures is to present an informal but precise introduction to a body of
concepts and methods of interest in number theory and string theory revolving around …

We show that after integrating over the zero mode in Liouville correlation functions, the
remaining functional integral resembles a free theory and may be evaluated by formally …

A bstract We study the multi-charged moments for two disjoint intervals in the ground state of
two 1+ 1 dimensional CFTs with central charge c= 1 and global U (1) symmetry: the …