We define a localised Euler class for isotropic sections, and isotropic cones, in SO(N) bundles. We use this to give an algebraic definition of Borisov-Joyce's sheaf counting invariants on Calabi-Yau 4-folds. When a torus acts, we prove a localisation result. This talk is based on the joint work with Richard. P. Thomas.

28 Oct 2020
3:15pm - 4:15pm
Where
https://hkust.zoom.us/j/9584764665 (Passcode: dt4fold)
Speakers/Performers
Dr. Jeongseok OH
Korea Institute for Advanced Study (KIAS)
Organizer(S)
Department of Mathematics
Contact/Enquiries
Payment Details
Audience
Alumni, Faculty and staff, PG students, UG students
Language(s)
English
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