BEGIN:VCALENDAR
VERSION:2.0
PRODID:icalendar-ruby
CALSCALE:GREGORIAN
X-WR-CALNAME:Algebraic Topology Seminar
X-WR-TIMEZONE:Eastern Time (US & Canada)
BEGIN:VEVENT
DTSTAMP:20260616T124808Z
UID:tag:localist.com\,2008:EventInstance_45835540419113
DTSTART:20240311T083000Z
DTEND:20240311T100000Z
DESCRIPTION:Speaker:  Stephen McKean (Harvard University) \n\nTitle: Motivi
 c Euler characteristics and power structures\n\nAbstract: There is a quadr
 atic form-valued version of the compactly supported Euler characteristic c
 oming from motivic homotopy. A feature of this Euler characteristic is tha
 t it descends to a ring homomorphism out of the Grothendieck ring of varie
 ties. In characteristic 0\, this Euler characteristic was constructed by R
 öndigs and later Arcila-Maya—Bethea—Opie—Wickelgren—Zakharevich\,
  who used Bittner’s blow up presentation of K_0(Var). In characteristic 
 not 2\, Azouri gave a characterization in terms of the six functor formali
 sm. I will discuss a hybrid approach using a sort of universal property of
  K_0(Var). I will then discuss power structures on K_0(Var) and the Grothe
 ndieck—Witt ring of quadratic forms\, and conclude with a conjecture rel
 ating these two power structures. This is joint work in progress with Dori
  Bejleri
GEO:42.358262;-71.090045
LOCATION:Building 2\, 131
SUMMARY:Algebraic Topology Seminar
URL;VALUE=URI:https://calendar.mit.edu/event/copy-of-copy-of-algebraic-topo
 logy-seminar
CATEGORIES:Conferences/Seminars/Lectures
END:VEVENT
END:VCALENDAR