Arkadij Bojko (SIMIS & Fudan University) - Universal Virasoro constraints for linear theories

Virasoro constraints were recently formulated for moduli of sheaves. The main difference compared to Gromov-Witten theory lies in the linearity of the former which allowed us (B.-Lim-Moreira) to derive sheaf-theoretic constraints from the geometric vertex algebras of Joyce. Our approach applies to more general linear categories. For both sheaves and representations of quivers, I will explain that Virasoro costraints determine primary states of the vertex algebra. This is already sufficient to illustrate the formulation for any linear theory, and it leads to the proof of many results via wall-crossing.