Time: 2017.12.05, 15:15–17:00
Location: Seminarraum 9, Oskar-Morgenstern-Platz 1, 2.Stock
Title: "Infinite symmetric group and combinatorial cobordisms."
Speaker: Yurii Neretin (Universität Wien)
Abstract: It is known that for infinite-dimensional groups $$G\supset K$$ double coset spaces $$K\setminus G/K$$ quite often admit natural multiplications (which can be considered as degenerations of convolutions at infinite-dimensional limits). We consider the case when $$G$$ is the product of 3 copies of infinite symmetric group and $$K$$ are subgroups in the diagonal $$K_0$$. It will be explained that unitary representations of $$G$$ generate in a natural way representations of certain category, whose morphisms are triangulated two-dimensional surfaces with special colorings and product of morphisms is similar to concatenation of cobordisms.