Seminario: On pointed Hopf algebras and racks

Mercoledì 20 Maggio 2015, ore 14:15 - Aula 2AB40 - Gastón Garcia

Mercoledì 20 Maggio 2015 alle ore 14:15 in Aula 2AB40, Gastón Garcia (La Plata) terrà una conferenza dal titolo "On pointed Hopf algebras and racks".

The study of finite dimensional pointed Hopf algebras over a fixed group G can be approached through the analysis of the Nichols algebras associated with simple Yetter-Drinfeld modules over the group G, which are parametrized by conjugacy classes in G and representations of the corresponding centralizer. The latter can be described in terms of racks and rack cocycles. In this direction it is crucial to establish criteria on a rack to make sure that the attached Nichols algebra is infinite dimensional for every cocycle. In this talk we will focus on the translation of existing results into criteria which allow inductive reasoning and how to apply them to conjugacy classes in simple groups of Lie type.
Based on a joint project with N. Andruskiewitsch and G. A. Garcia.