BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Memento EPFL//
BEGIN:VEVENT
SUMMARY: Two constructible functions on the Hilbert scheme of points.
DTSTART:20121220T151500
DTEND:20121220T170000
DTSTAMP:20260407T105914Z
UID:e756562e2296df62c4e0fb44da903731f942121afd09b7dba9c2325a
CATEGORIES:Conferences - Seminars
DESCRIPTION:Andrew Morrison\, ETHZ\nWe discuss the values of two natural f
 unctions on the Hilbert scheme of points on a threefold.\n\nThe first is g
 iven by the dimension of the tangent space. Unlike the Hilbert scheme of p
 oints on a surface the moduli scheme in three dimensions is not smooth so 
 the dimension of the tangent space can jump. However we will see that the 
 dimension always jumps by a multiple of two preserving the parity of the c
 onstructible function. During the proof we will also see that the commutin
 g variety always has a tangent space of even dimension.\n\nThe second inte
 ger valued function is the Behrend function. This function associates to a
  scheme with a symmetric obstruction theory a Donaldson-Thomas type invari
 ant. In the case of the Hilbert scheme of n points on a threefold we show 
 that this function is constant with value (-1)^n. This implies that the co
 mponents of this Hilbert scheme are generically reduced.
LOCATION:CM 1 100 http://plan.epfl.ch/?lang=fr&room=cm1100
STATUS:CANCELLED
END:VEVENT
END:VCALENDAR