Seminars

Lorenzo Ruggeri

Tsinghua University, Beijing

Exact Results for SQFTs on Spaces with Conical Singularities

I will discuss exact results for SQFTs on spaces with conical singularities, both orbifolds with deficit angles and branched covers with surplus angles. To compute these results, I will show how, in both cases, the behaviour of SQFTs near the singularity is reproduced by the insertion of Gukov-Witten defects on a smooth space. This approach allows the computation of perturbative and, in dimensions four and above, instantonic contributions for a large class of spaces and for different ways to preserve supersymmetry. Moreover, contributions from fluxes are obtained from perturbative ones dimensionally reducing along a non-trivial fiber. Interestingly, spaces with the same parameters controlling the surplus or deficit angles have matching partition functions. I will conclude by highlighting possible directions for future research, including non-trivial checks of AdS/CFT and exact results on spaces with orbifold singularities $\mathbb{C}^2/\Gamma$, where $\Gamma$ is a finite subgroup of SU(2).