The second in a two-volume set, for researchers into finite groups, geometry and algebraic combinatorics.

This second volume in a two-volume set provides a complete self-contained proof of the classification of geometries associated with sporadic simple groups: Petersen and tilde geometries. It contains a study of the representations of the geometries under consideration in GF(2)-vector spaces as well as in some non-Abelian groups. The central part is the classification of the amalgam of maximal parabolics, associated with a flag transitive action on a Petersen or tilde geometry. By way of their systematic treatment of group amalgams, the authors establish a deep and important mathematical result.

The second in a two-volume set, for researchers into finite groups, geometry and algebraic combinatorics.

This book is the first volume in a two-volume set, which will provide the complete proof of classification of two important classes of geometries, closely related to each other: Petersen and tilde geometries. There is an infinite family of tilde geometries associated with nonsplit extensions of symplectic groups over a field of two elements. Besides that there are twelve exceptional Petersen and tilde geometries. These exceptional geometries are related to sporadic simple groups, including the famous Monster group and this volume gives a construction for each of the Petersen and tilde geometries that provides an independent existence proof for the corresponding automorphism group. Important applications of Petersen and tilde geometries are considered, including the so-called Y-presentations for the Monster and related groups, and a complete identification of Y-groups is given. This is an essential purchase for researchers in finite group theory, finite geometries and algebraic combinatorics.

Important monograph on finite group theory.