Speaker: Karen Meagher, University of Regina Title: Derangement graphs and the intersection density of permutation groups Abstract: Two permutations are intersecting if they both map some $i$ to the same point, equivalently, permutations $\sigma$ and $\pi$ are intersecting if and only if $\pi^{-1}\sigma$ has a fixed point. A set of permutations is called intersecting if any two permutations in the set are intersecting. For any transitive group the stabilizer of a point is an intersecting set. The intersection density of a permutation…