Spectra of non-commutative dynamical systems and graphs related to fractal groups
arXiv:math/0012174 · doi:10.1016/S0764-4442(00)01658-X
Abstract
We study spectra of noncommutative dynamical systems, representations of fractal groups, and regular graphs. We explicitly compute these spectra for five examples of groups acting on rooted trees, and in three cases obtain totally disconnected sets.
Short note summing up math.GR/9910102