It is shown that the -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.
Cite this article
B. Eckmann, Approximating -Betti numbers of an amenable covering by ordinary Betti numbers. Comment. Math. Helv. 74 (1999), no. 1, pp. 150–155DOI 10.1007/S000140050081