Branes: from free fields to general backgrounds
Abstract
Motivated by recent developments in string theory, we study the structure of boundary conditions in arbitrary conformal field theories. A boundary condition is specified by two types of data: first, a consistent collection of reflection coefficients for bulk fields on the disk; and second, a choice of an automorphism ω of the fusion rules that preserves conformal weights and can be implemented on the spaces of chiral blocks. Nontrivial automorphisms ω correspond to Dbrane configurations for arbitrary conformal field theories. The choice of the fusion rule automorphism ω amounts to fixing the dimension and certain global topological features of the Dbrane world volume and the background gauge field on it. We present evidence that for fixed choice of ω the boundary conditions are classified as the irreducible representations of some commutative associative algebra, a generalization of the fusion rule algebra. Each of these irreducible representations corresponds to a choice of the moduli for the world volume of the Dbrane and the moduli of the flat connection on it.
 Publication:

Nuclear Physics B
 Pub Date:
 October 1998
 DOI:
 10.1016/S05503213(98)003526
 arXiv:
 arXiv:hepth/9712257
 Bibcode:
 1998NuPhB.530...99F
 Keywords:

 High Energy Physics  Theory
 EPrint:
 56 pages, LaTeX2e. Typos corrected