BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Drupal iCal API//EN X-WR-CALNAME:Events items teaser X-WR-TIMEZONE:America/Toronto BEGIN:VTIMEZONE TZID:America/Toronto X-LIC-LOCATION:America/Toronto BEGIN:DAYLIGHT TZNAME:EDT TZOFFSETFROM:-0500 TZOFFSETTO:-0400 DTSTART:20250309T070000 END:DAYLIGHT BEGIN:STANDARD TZNAME:EST TZOFFSETFROM:-0400 TZOFFSETTO:-0500 DTSTART:20241103T060000 END:STANDARD END:VTIMEZONE BEGIN:VEVENT UID:68ab26ba8feb2 DTSTART;TZID=America/Toronto:20250320T140000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20250320T150000 URL:/combinatorics-and-optimization/events/algebraic-an d-enumerative-combinatorics-seminar-allen SUMMARY:Algebraic and enumerative combinatorics seminar-Allen Knutson CLASS:PUBLIC DESCRIPTION:Summary \n\nTITLE: Schubert calculus by counting puzzles\n\nSp eaker\n Allen Knutson\n\nAffiliation\n Cornell\n\nLocation\n MC 5479\n\n  ABSTRACT: There are three rings-with-bases whose multiplicative\nstructur e constants are computed by the same rule: the cohomology ring\nof the Gra ssmannian Gr(k\,n)\, the representation ring of GL_k (made by\nstabilizing the previous in n)\, and one made by summing all\nrepresentation rings of the symmetric groups (made by stabiliizing the\nprevious in k). The most famous rules\, typically involving counting\nYoung tableaux\, are for the most stable version\, but the unstable\nversion admits the most generaliza tions\, to K-theory\, equivariant\ncohomology\, quantum cohomology\, and t o other homogeneous varieties.\nI'll explain how to compute the multiplica tion in many of these cases\nby counting \"puzzles\".\n\nThis work is join t with Terry Tao and Paul Zinn-Justin.\n\nTHERE WILL BE A PRE-SEMINAR PRES ENTING RELEVANT BACKGROUND AT THE\nBEGINNING GRADUATE LEVEL STARTING AT 1P M\,\n DTSTAMP:20250824T145034Z END:VEVENT END:VCALENDAR