Topological Orbifold Models and Quantum Cohomology Rings
نویسنده
چکیده
We discuss the toplogical sigma model on an orbifold target space. We describe the moduli space of classical minima for computing correlation functions involving twisted operators, and show, through a detailed computation of an orbifold of CP by the dihedral group D4, how to compute the complete ring of observables. Through this procedure, we compute all the rings from dihedral CP orbifolds; we note a similarity with rings derived from perturbed D−series superpotentials of the A−D−E classification of N = 2 minimal models. We then consider CP/D4, and show how the techniques of topological-antitopological fusion might be used to compute twist field correlation functions for nonabelian orbifolds.
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