|Date: Tuesday, October 06, 2015
Title: Spectra of Schreir graphs of groups of intermediate growth and Schroedinger operators
Abstract: We will focus on the question how the spectrum of the weighted Laplacian on a Schreier graph of a finitely generated group depends on weight. It will be shown that the nature of spectrum may drastically be changed after change of weights. This will be demonstrated on the example of a group of intermediate (between polynomial and exponential) growth constructed by the speaker to solve in 1984 the Milnor's problem. Surprisingly, the results about spectra of random Schroedinger operators will be used for this goal as well as some ideas from the theory of aperiodic order.
Speaker: Rostislav Grigorchuk
Institution: Texas A & M University