Wolfgang Lerche (CERN Geneva):
Superpotentials, N=1 Special Geometry and Mirror Symmetry
I will present recent progress in computing non-perturbatively exact
superpotentials of certain N=1 supersymmetric string compactifications.
The efficient and systematic method relies on a non-trivial
generalization of mirror symmmetry to Calabi-Yau manifolds with
D-branes on top of them. The approach puts the computation of N=1
superpotentials W on a footing similar to the familiar computation of
the prepotential F in N=2 theories; the main new physical ingredient is
that besides the usual closed string instantons, also disk instantons
from the open string sector contribute. The whole framework may be
viewed as the N=1 counterpart of the well-known N=2 "special geometry".