We show that given a Frobenius algebra there is a unique notion of its second quantization, which is the sum over all symmetric group quotients of n–th tensor powers, where the quotients are given by symmetric group twisted Frobenius algebras. To this end, we consider the setting of Frobenius algebras given by functors from geometric categories whose objects are endowed with geometric group act...

We propose and give strong evidence for a duality relating Type II theories on CalabiYau spaces and heterotic strings on K3× T , both of which have N = 2 spacetime supersymmetry. Entries in the dictionary relating the dual theories are derived from an analysis of the soliton string worldsheet in the context of N = 2 orbifolds of dual N = 4 compactifications of Type II and heterotic strings. In ...