MenuEvents for 11/30/2017 from all calendars
Noncommutative Geometry Seminar
Time: 2:00PM - 3:00PM
Location: *BLOC 220*
Speaker: Ronghui Ji, IUPUI
Title: From relative amenability to relative soficity for countable groups
Abstract: We define a relative soficity for a countable group with respect to a family of subgroups. A group is sofic if and only if it is relatively sofic with respect to the family consisting of only the trivial subgroup. When a group is relatively amenable with respect to a family of subgroups, then it is relatively sofic with respect to the family. We show that if a group is relatively sofic with respect to a family of sofic subgroups, then the group is sofic. This in particular generalizes a result of Elek and Szabo. An example of relatively amenable group G with respect to an infinite family of subgroups F is constructed so that G is not relatively amenable with respect to any finite subfamily of F.
Algebra and Combinatorics Seminar
Time: 2:45PM - 3:45PM
Location: BLOC 628
Speaker: Cesar Galindo, Universidad de los Andes
Title: Pointed finite tensor categories over abelian groups
Abstract: In this talk we will give a characterization of finite pointed tensor categories obtained as de-equivariantizations of finite-dimensional pointed Hopf algebras over abelian groups only in terms of the (cohomology class of the) associator of the pointed part. As an application, we will prove that every coradically graded pointed finite braided tensor category is a de-equivariantization of a finite dimensional pointed Hopf algebras over an abelian group. This talk is base on arXiv:1707.05230, joint work with Iván Angiono.
Geometry Seminar
Time: 3:00PM - 4:00PM
Location: BLOC 220
Speaker: Patricio Gallardo , Washington University, St. Louis
Title: Point and line to plane
Abstract: We will discuss higher dimensional generalizations of the moduli of n labeled points in the sphere. In particular, we will compare the standard generalizations, constructed using the minimal model program, with new constructions based on configuration spaces. Most of the results are joint work with E. Routis.
