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TZID:Europe/Vienna
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DTSTART:20200329T030000
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DTSTART:20191027T020000
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DTSTAMP:20260406T074258Z
UID:5c3337d560ff7441768214@ist.ac.at
DTSTART:20191107T133000
DTEND:20191107T153000
DESCRIPTION:Speaker: Nadir Fasola\nhosted by Tamas Hausel\nAbstract: Nested
  instantons have been recently introduced in physics as objects describing
  the parabolic reduction of gauge connections at punctures on Riemann surf
 aces and are understood in terms of moduli spaces of stable representation
 s of certain quivers. The relevant physical quantities compute some of the
 ir virtual invariants\, which in some case have a connection to the cohomo
 logy of character varieties. We will study the moduli spaces of stable rep
 resentations of a class of nested instantons quivers and show how these ar
 e isomorphic to moduli spaces of (suitably defined) flags of framed torsio
 n-free sheaves on the projective plane\, reducing in rank one to nested Hi
 lbert schemes of points on the complex plane. The existence of a perfect o
 bstruction theory and the quiver description enable us to compute virtual 
 invariants of flags of sheaves and to generalize their computation to nest
 ed Hilbert schemes of points on (smooth) toric surfaces.
LOCATION:Heinzel Seminar Room / Office Bldg West (I21.EG.101)\, ISTA
ORGANIZER:boosthui@ist.ac.at
SUMMARY:Nadir Fasola: Flags of sheaves\, quivers and nested instantons
URL:https://talks-calendar.ista.ac.at/events/2143
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