BEGIN:VCALENDAR
VERSION:2.0
PRODID:researchseminars.org
CALSCALE:GREGORIAN
X-WR-CALNAME:researchseminars.org
BEGIN:VEVENT
SUMMARY:Arkadij Bojko (Academia Sinica)
DTSTART:20240502T083000Z
DTEND:20240502T093000Z
DTSTAMP:20260422T161058Z
UID:HKUST-AG/44
DESCRIPTION:Title: <a href="https://researchseminars.org/talk/HKUST-AG/44/
 ">Wall-crossing for Calabi-Yau fourfolds and applications</a>\nby Arkadij 
 Bojko (Academia Sinica) as part of Algebra and Geometry Seminar @ HKUST\n\
 nLecture held in 3598.\n\nAbstract\nMy work focuses on proving wall-crossi
 ng for sheaves and pairs on Calabi-Yau fourfolds. It is desirable that the
  end result can have many concrete applications to existing conjectures. F
 or this purpose\, I introduce a new structure into the picture - formal fa
 milies of vertex algebras. Apart from being a natural extension of the ver
 tex algebras introduced by Joyce\, they allow to wall-cross with insertion
 s instead of the plain virtual fundamental classes.  Many fundamental hurd
 les needed to be overcome to prove wall-crossing in this setting. They inc
 luded constructing Calabi-Yau four obstruction theories on (enhanced) mast
 er spaces and showing that the invariants counting semistable torsion-free
  sheaves are well-defined. At the end\, I will use the complete package to
  address existing conjectures with applications to 3-fold DT/PT correspond
 ences.\n
LOCATION:https://researchseminars.org/talk/HKUST-AG/44/
END:VEVENT
END:VCALENDAR