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UID:20260502T121218EDT-6433LHuV1I@132.216.98.100
DTSTAMP:20260502T161218Z
DESCRIPTION:Title: Distances in trees and inequalities for matroids\n\nAbst
 ract: The distance matrix of a tree appears in a range of contexts\, from 
 phylogenetics to physical chemistry. I will describe a new result about th
 e spectrum of this matrix\, one that gives affirmative answers to some que
 stions about matroid positivity properties. Those are both strengthenings 
 of Mason’s conjectures about the log-concavity of sequence of numbers of i
 ndependent sets of a matroid\, proposed by Dowling in 1980 and much more r
 ecently by Giansiracusa\, Rincón\, Schleis\, Ulirsch. At the heart is a ch
 aracterization of the gross substitutes property from economics in terms o
 f the Lorentzian property of a certain generating function.\n\nLocation: P
 K-4323 of UQAM’s Président-Kennedy Building.\n
DTSTART:20260501T150000Z
DTEND:20260501T160000Z
SUMMARY:Graham Denham (University Of Western Ontario)
URL:/channels/channels/event/graham-denham-university-
 western-ontario-372797
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