Title: Approximating $\ell_2$ -Betti numbers of an amenable covering by ordinary Betti numbers
Abstract:It is shown that the \ell_2 -Betti numbers of an amenable covering of a finite cell-complex can be approximated by ordinary Betti numbers of the finite Fmlner subcomplexes. This is a new proof, using ...It is shown that the \ell_2 -Betti numbers of an amenable covering of a finite cell-complex can be approximated by ordinary Betti numbers of the finite Fmlner subcomplexes. This is a new proof, using simple homological arguments, of a recent result of Dodziuk and Mathai.Read More