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DTSTART:20070311T020000
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BEGIN:VEVENT
DTSTAMP:20260316T104615
DTSTART;TZID=America/Detroit:20260414T160000
DTEND;TZID=America/Detroit:20260414T170000
SUMMARY:Lecture / Discussion:Colloquium: Total positivity: combinatorics\, geometry\, and representation theory
DESCRIPTION:An invertible matrix is called totally positive if all of its minors are positive. Over the past several decades\, this classical notion has evolved into a rich and far-reaching theory. In a foundational 1994 work\, Lusztig extended total positivity to arbitrary split real reductive groups and their flag varieties\, uncovering remarkable connections with combinatorics\, geometry\, and representation theory. Since then\, total positivity has emerged in a wide range of contexts\, from cluster algebras and higher Teichmüller theory to the geometry\nunderlying the amplituhedron.\n\nIn this talk\, I will give an overview of the basic theory of total positivity and describe some recent developments. I will explain how the subject is intertwined with combinatorial structures such as Bruhat order and shellable posets\, with representation theory through Lusztig's canonical basis\, and with topology through the study of regular CW complexes and with an unexpected appearance of the Poincaré econjecture. I will also discuss recent progress on the conjectures of Björner\, of Fomin-Zelevinsky\, as well as further conjectures of Postnikov\, Galashin-Karp-Lam\, and Williams. This talk is based on my joint works with Huanchen Bao and with Kaitao Xie.
UID:144881-21896089@events.umich.edu
URL:https://events.umich.edu/event/144881
CLASS:PUBLIC
STATUS:CONFIRMED
CATEGORIES:Mathematics
LOCATION:
CONTACT:
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BEGIN:VEVENT
DTSTAMP:20251119T183929
DTSTART;TZID=America/Detroit:20260421T160000
DTEND;TZID=America/Detroit:20260421T170000
SUMMARY:Lecture / Discussion:Application workshop
DESCRIPTION:TBA
UID:140091-21886601@events.umich.edu
URL:https://events.umich.edu/event/140091
CLASS:PUBLIC
STATUS:CONFIRMED
CATEGORIES:Mathematics
LOCATION:East Hall - 1360
CONTACT:
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BEGIN:VEVENT
DTSTAMP:20260310T061642
DTSTART;TZID=America/Detroit:20260908T160000
DTEND;TZID=America/Detroit:20260908T170000
SUMMARY:Lecture / Discussion:Colloquium: TBA
DESCRIPTION:TBA
UID:146386-21898980@events.umich.edu
URL:https://events.umich.edu/event/146386
CLASS:PUBLIC
STATUS:CONFIRMED
CATEGORIES:Mathematics
LOCATION:East Hall - 1360
CONTACT:
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BEGIN:VEVENT
DTSTAMP:20251028T082420
DTSTART;TZID=America/Detroit:20261110T160000
DTEND;TZID=America/Detroit:20261110T170000
SUMMARY:Lecture / Discussion:2026 Van Eenan Lectures: Ronnie Sircar
DESCRIPTION:TBA
UID:141176-21888297@events.umich.edu
URL:https://events.umich.edu/event/141176
CLASS:PUBLIC
STATUS:CONFIRMED
CATEGORIES:Mathematics
LOCATION:East Hall - 1360
CONTACT:
END:VEVENT
BEGIN:VEVENT
DTSTAMP:20251028T082420
DTSTART;TZID=America/Detroit:20261111T160000
DTEND;TZID=America/Detroit:20261111T170000
SUMMARY:Lecture / Discussion:2026 Van Eenan Lectures: Ronnie Sircar
DESCRIPTION:TBA
UID:141176-21888405@events.umich.edu
URL:https://events.umich.edu/event/141176
CLASS:PUBLIC
STATUS:CONFIRMED
CATEGORIES:Mathematics
LOCATION:East Hall
CONTACT:
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BEGIN:VEVENT
DTSTAMP:20251028T082420
DTSTART;TZID=America/Detroit:20261112T160000
DTEND;TZID=America/Detroit:20261112T170000
SUMMARY:Lecture / Discussion:2026 Van Eenan Lectures: Ronnie Sircar
DESCRIPTION:TBA
UID:141176-21888406@events.umich.edu
URL:https://events.umich.edu/event/141176
CLASS:PUBLIC
STATUS:CONFIRMED
CATEGORIES:Mathematics
LOCATION:East Hall
CONTACT:
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