BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250716T154926EDT-3488NNFTV7@132.216.98.100 DTSTAMP:20250716T194926Z DESCRIPTION:Macdonald polynomials\, diffusivity\, and Kerov conjecture.\n\n Pioneers of the study of totally positive (all minors non-negative) matric es\, Krein\, Schoenberg\, Karlin\, were motivated by analytic questions\, but the topic has later percolated to the domain of representation theory and algebraic combinatorics. This talk is about one story illustrating thi s interplay of algebra and analysis. In 1952 Edrei et al. used Nevanlinna theory to prove the classification of the totally positive infinite upper triangular Toeplitz matrices. In 1960s-1980s this problem was connected to the representation theory of the infinite symmetric group by Thoma\, Vers hik\, Kerov. In 1992 Kerov has conjectured a generalization of this theore m based on the notion of Macdonald polynomials. Over the years several spe cial cases related to different representation-theoretic settings were pro ved. I will talk about a recent proof of the general case\, that required a new approach. One of the key difficulties was to find a replacement of t he Nevanlinna theory argument. The new argument is based on certain diffus ivity on the branching graph of Macdonald polynomials.\n DTSTART:20180223T190000Z DTEND:20180223T200000Z LOCATION:Room VCH-3830\, CA\, Université Laval SUMMARY:Konstantin Matveev\, Brandeis University URL:/mathstat/channels/event/konstantin-matveev-brande is-university-285190 END:VEVENT END:VCALENDAR