Centralizers of Involutions in Finite Simple Groups
نویسنده
چکیده
It has been known for a long time that the structure of a finite simple group is intimately connected with the structure of the centralizers of its involutions. An old result of Brauer and Fowler asserts, in fact, that there are at most a finite number of simple groups in which the centralizer of an involution has a given structure. A more specific, pioneering result of Brauer established that the groups PSL(3, q) with q = — l(mod 4) and the Mathieu group M u were the only simple groups in which the centralizer of an involution was isomorphic to a homomorphic image of GL(2, q) by a central subgroup of odd order.
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