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DTSTAMP:20260424T143433Z
UID:1714042800@ist.ac.at
DTSTART:20240425T130000
DTEND:20240425T150000
DESCRIPTION:Speaker: Young-Hoon Kiem\nhosted by Tamas Hausel / Jakub Löwit
 \nAbstract: Modern enumerative geometry is about integrals of cohomology c
 lasses against virtual fundamental classes of moduli spaces. When the perf
 ect obstruction theory of a moduli space admits a cosection\, the virtua
 l fundamental class is localized to the zero locus of the cosection. When 
 the cosection can be enhanced to a (-1)-shifted closed 1-form\, the zero l
 ocus admits a (-2)-shifted symplectic structure and hence a virtual fundam
 ental class due to a recent construction of Oh-Thomas. I will talk about a
  joint work with Hyeonjun Park where we prove that the two virtual fundame
 ntal classes coincide up to sign. When applied to a shifted form of Lagra
 nge multipliers method\, the result gives us an immediate proof of the q
 uantum Lefschetz principle by Chang-Li. 
LOCATION:Heinzel Seminar Room (I21.EG.101)\, Office Building West\, ISTA\, 
 ISTA
ORGANIZER:birgit.oosthuizen-noczil@ist.ac.at 
SUMMARY:Young-Hoon Kiem: Shifted Lagrange multipliers method
URL:https://talks-calendar.ista.ac.at/events/4750
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