Dynamical Topology Change in M Theory

We study topology change in M theory compactifications on Calabi-Yau three-folds in the presence of G flux (the four form field strength). In particular, we discuss vacuum solutions in strongly coupled heterotic string theory in which the topology change is inevitable within a single spacetime background. For rather generic choices of initial conditions, the field equations drive the Kähler moduli outside the classical moduli space of a Calabi-Yau manifold. Consistency of the solution suggests that degenerate flop curves — just as wrapped M theory fivebranes — carry magnetic charges under the four form field strength. E-mail: [email protected] E-mail: [email protected] E-mail: [email protected] Address after September 1, 2000