Total Positivity in Three Flavors

Come on down to the Total Positivity ice cream parlor! We've got the century-old theory that brings together linear algebra, combinatorics, theoretical physics, and more! And today we're serving it ice-cold in three delicious flavors: GL(n), Pólya Frequency Series, and Loop Groups. Each scoop will be served with a delicious sauce (factorization theorem) and sprinkles (combinatorial applications). Please note: ice cream will not actually be served, but I promise this talk will be sweet!