SMS scnews item created by donnelly at Thu 11 Sep 2014 1944
Type: Seminar
Distribution: World
Expiry: 25 Sep 2014
Calendar1: 18 Sep 2014 1500-1600
CalLoc1: Carslaw 535A
Auth: donnelly@seurat.maths.usyd.edu.au

Computational Algebra Seminar: Saunders -- Exceptional Quotients of Permutation Groups

Neil Saunders (University of Bristol)

Thursday September 18, 3pm, Carslaw 535

"Exceptional Quotients of Permutation Groups"   

The minimal permutation degree of a finite group $G$ is the smallest
non-negative integer $n$ such that $G$ embeds inside $Sym(n)$. This
invariant is easy to define but very difficult to calculate in general.
Moreover, it doesn’t behave well under algebraic constructions such as
direct product and homomorphic image. For example, it is possible for the
minimal degree of a homomorphic image to be strictly larger than that of
the group -- such groups are called ’exceptional’.

In this talk, I will describe how this invariant maybe calculated by a 
greedy algorithm for nilpotent groups and report on recent work with
Britnell and Skyner on classifying exceptional groups of order p^5.