中央研究院數學研究所

Algebraic Geometry Seminar

Virtual cycles on projective completions

2024/06/05 (Wed.) 15:30~16:30

Date : 2024/06/05 (Wed.) 15:30~16:30
Location : Seminar Room 638, Institute of Mathematics (NTU Campus)
Speaker : Jeongseok Oh (Seoul National University)
Organizer : Adeel Khan (AS)
Website : https://wiki.preschema.com/ag-seminar
Abstract : For a compact quasi-smooth derived scheme M with (-1)-shifted cotangent bundle N, there are at least two ways to localise the virtual cycle of N to M via torus and cosection localisations, introduced by Jiang-Thomas. We produce two virtual cycles on the projective completion of N and one on the projectivisation of N; and show the ones on the completion push down to Jiang-Thomas cycles and the one on the projectivisation computes the difference. Using similar ideas we give an expression of the difference of the quintic and t-twisted quintic GW invariants of Guo-Janda-Ruan.