This review is devoted to open strings, and in particular to the often surprising features of
their spectra. It follows and summarizes developments that took place mainly at the …

We study the spectrum of open strings on AdS2 branes in AdS3 in an NS–NS background,
using the SL (2, R) WZW model. When the brane carries no fundamental string charge, the …

A bstract String theory on AdS 3× S 3× 𝕋 4 with minimal k= 1 NS-NS flux can be described in
terms of a free field worldsheet theory in the hybrid formalism. We construct various D …

We present a comprehensive analysis of branes in the euclidean 2D black hole (cigar). In
particular, exact boundary states and annulus amplitudes are provided for D0-branes which …

We exhibit a simple class of exactly marginal “double-trace” deformations of two-
dimensional conformal field theories (CFTs) which have AdS 3 duals, in which the …

A bstract We show that the geometric interpretation of D-branes in WZW models as twisted
conjugacy classes persists in the λ-deformed theory. We obtain such configurations by …

We construct boundary states for the AdS2 D-branes in AdS3. We show that, in the semi-
classical limit, the boundary states correctly reproduce geometric configurations of these …

We study D-branes that preserve a diagonal SL (2) affine Lie algebra in string theory on
AdS3. We find three classes of solutions, corresponding to the following representations of …

In the SL (2) conformal field theory, we write down and analyze the analytic expression of
the three-point functions of generic primary fields with definite SL (2) weights. Using these …

In this thesis we explore the holographic duality between string theory on AdS3 spacetimes
and two-dimensional conformal field theories through worldsheet methods. Specifically, we …