$GL(3,2)$ Is Isomorphic to $PSL(2,7)$: Yet Another Proof,   H. F. Mattson, jr,   Syracuse University,  Wed, 3 February, 2010,   1:00 p.m. A-143


The several proofs in the literature of the isomorphism of the title are well summarized in the recent paper Ezra Brown & Nicholas Loehr, ``Why is $PSL(2,7) [isomorphic to] GL(3,2)$?' Amer. Math. Monthly 116 (2009) 727-732.

In the October Monthly. The purpose of this talk is to present another proof, inspired by, but not reliant on, the theory of error-correcting codes. Undergraduates with basic knowledge of linear algebra and the theory of groups should be able to fill in any gaps in the argument. Indeed, students need know barely more than the definitions in these topics.