Finite simple groups as expanders

Proc Natl Acad Sci U S A. 2006 Apr 18;103(16):6116-9. doi: 10.1073/pnas.0510337103. Epub 2006 Apr 6.

Abstract

We prove that there exist k in and 0 < epsilon in such that every non-abelian finite simple group G, which is not a Suzuki group, has a set of k generators for which the Cayley graph Cay(G; S) is an epsilon-expander.