Displaying 41 – 60 of 147

Showing per page

Finite simple groups of Lie type as expanders

Alexander Lubotzky (2011)

Journal of the European Mathematical Society

We prove that all finite simple groups of Lie type, with the exception of the Suzuki groups, can be made into a family of expanders in a uniform way. This confirms a conjecture of Babai, Kantor and Lubotzky from 1989, which has already been proved by Kassabov for sufficiently large rank. The bounded rank case is deduced here from a uniform result for S L 2 which is obtained by combining results of Selberg and Drinfeld via an explicit construction of Ramanujan graphs by Lubotzky, Samuels and Vishne.

Groups generated by two mutually Engel periodic elements

H. Heineken (2000)

Bollettino dell'Unione Matematica Italiana

Scriviamo [ x , y ] = [ x , 1 y ] ed [ [ x , k y ] , y ] = [ x , k + 1 y ] . Cerchiamo gruppi S L 2 , q con generatori x , y tali che [ x , m y ] = x ed [ y , n x ] = y per alcuni numeri naturali m , n .

Nonassociativity in VOA theory and finite group theory

Jr. Griess, Robert L. (2010)

Commentationes Mathematicae Universitatis Carolinae

We discuss some examples of nonassociative algebras which occur in VOA (vertex operator algebra) theory and finite group theory. Methods of VOA theory and finite group theory provide a lot of nonassociative algebras to study. Ideas from nonassociative algebra theory could be useful to group theorists and VOA theorists.

OD-characterization of almost simple groups related to L 2 ( 49 )

Liang Cai Zhang, Wu Jie Shi (2008)

Archivum Mathematicum

In the present paper, we classify groups with the same order and degree pattern as an almost simple group related to the projective special linear simple group L 2 ( 49 ) . As a consequence of this result we can give a positive answer to a conjecture of W. J. Shi and J. X. Bi, for all almost simple groups related to L 2 ( 49 ) except L 2 ( 49 ) · 2 2 . Also, we prove that if M is an almost simple group related to L 2 ( 49 ) except L 2 ( 49 ) · 2 2 and G is a finite group such that | G | = | M | and Γ ( G ) = Γ ( M ) , then G M .

Currently displaying 41 – 60 of 147