BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Kirsten Wickelgren (Duke) DTSTART:20210322T203000Z DTEND:20210322T213000Z DTSTAMP:20260423T024542Z UID:MITTop/34 DESCRIPTION:Title: An excess intersection formula\nby Kirsten Wickelgren (Duke) as part o f MIT topology seminar\n\n\nAbstract\nOne expects the intersection of a d and n-d dimensional subscheme or submanifold of an n-dimensional one to be 0 dimensional. When this is not the case\, such intersections are often c alled excess intersections\, and arise when considering questions such as 'How many conics are tangent to 5 conics in the plane?' We consider cohomo logy classes in oriented Chow and Hermitian K-theory associated to excess intersections\, and use some recent duality results of Eisenbud and Ulrich to give an excess intersection formula. We compute some examples giving a rithmetic refinements of counts classically valid only over algebraically closed fields. This is joint work with Tom Bachmann.\n LOCATION:https://researchseminars.org/talk/MITTop/34/ END:VEVENT END:VCALENDAR