## Lethbridge Number Theory and Combinatorics Seminar: Joy Morris

- Date: 02/06/2017
- Time: 12:00

University of British Columbia

Oriented Regular Representations

An oriented graph is a digraph with at most one arc between any pair of vertices.

We say that the action of a group on a set of points is regular if it is sharply transitive; that is, there is exactly one group element mapping any point to any other point. An oriented regular representation (ORR) for a group G is an oriented graph whose automorphism group is isomorphic to the regular action of G on the vertices. In 1980, Babai asked which groups admit an ORR. I will discuss this problem, and present joint work with Pablo Spiga in which we showed that every non-solvable group admits an ORR.

Location: B660 University Hall

Web page: http://www.cs.uleth.ca/~nathanng/ntcoseminar/