Integers in the open string

Abstract

We show that the $Y_{ab}^c$ of Pradisi-Sagnotti-Stanev are indeed integers, and we prove a conjecture of Borisov-Halpern-Schweigert. We indicate some of the special features which arise when the order of the modular matrix T is odd. Our arguments are general, applying to arbitrary ``parent'' RCFT assuming only that T has odd order.

8 pp, plain tex

References in corpus (4)

• Boundary Conditions in Rational Conformal Field Theories
• Conformal boundary conditions and three-dimensional topological field theory
• Klein Bottles and Simple Currents
• Permutation orbifolds

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