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arXiv · hep-th/9712257

Branes: from free fields to general backgrounds

J. Fuchs·C. Schweigert
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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. Non-trivial automorphisms $ω$ correspond to D-brane 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 D-brane 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 D-brane and the moduli of the flat connection on it.

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J. Fuchs, C. Schweigert. 1998-01-28. Branes: from free fields to general backgrounds. https://doi.org/10.1016/s0550-3213(98)00352-6

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