Emanuel Diaconescu

A vertex formalism for degenerate torus actions.


In this talk we will construct a vertex formalism for the residual Gromov-Witten theory of nontoric Calabi-Yau threefolds with degenerate torus action. As an application of this formalism we will present a construction of the Gromov-Witten partition function of local nontoric del Pezzo surfaces.