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DTSTAMP:20221204T203809Z
UID:20221204T193809-1276843478@www.mn.uio.no
DTSTART:20221103T131500Z
DTEND:20221103T150000Z
LOCATION:NHA B1120
DESCRIPTION:I will explain how a recent “universal wall-crossing” framewor
k of Joyce works in equivariant K-theory, which I view as a multiplicativ
e refinement of equivariant cohomology. Enumerative invariants, possibly
of strictly semistable objects living on the walls, are controlled by a c
ertain (multiplicative version of) vertex algebra structure on the K-homo
logy groups of the ambient stack. In very special settings like refined V
afa-Witten theory, one can obtain some explicit formulas. For moduli stac
ks of quiver representations, this geometric vertex algebra should be dua
l in some sense to the quantum loop algebras that act on the K-theory of
stable loci.
SUMMARY:Henry Liu (Oxford) - Multiplicative vertex algebras and wall-cross
ing in equivariant K-theory
URL:https://www.mn.uio.no/math/english/research/groups/algebra/events/semi
nars/2022/liu.html
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