Normal Subgroup Growth of Linear Groups: the (G2; F4;E8)-Theorem
arXiv:1108.1044
Abstract
Let G be a finitely generated group and M_n(G) the number of its normal subgroup subgroups of index at most n. For linear groups G we show that M_n(G) can grow polynomially in n only if the semisimple part of the Zariski closure of G has simple components only of type G2, F4 or E8 (and in this case indeed this can happened!)
This is an old paper, we upload it now in order for it to have an online access