SEMINAR: Groups and Combinatorics Seminar: Recent studies on symmetric designs

Time and place: 3pm Friday 23 January in MLR1.

Speaker: Seyed Hassan Alavi (Buali Sina University)

Title: Recent studies on symmetric designs.

Abstract: A symmetric design (v,k,l) is an incidence structure consisting of a set of v points and a set of v blocks with an incidence relation such that every block is incident with exactly k points, and every pair of points is incident with exactly l blocks. An automorphism group of a symmetric design is a group of permutations on points of the design which maps blocks to blocks and preserves incidence and non-incidence. The main part of this talk is devoted to giving a survey on recent study of symmetric designs which admit a group of automorphisms acting primitively (resp. transitively) on the set of points (resp. blocks).