Mathematical Physics and Harmonic Analysis Seminar

Date: November 16, 2018

Time: 1:50PM - 2:50PM

Location: BLOC 628

Speaker: Jari Taskinen, University of Helsinki

Title: Structure and existence of gaps of essential spectra of elliptic boundary problems in periodic waveguides

Abstract: We review some recent joint works with Sergei Nazarov and others concerning spectral elliptic boundary value problems in periodic waveguides. We consider the structure of the essential spectrum e.g. for the Neumann Laplacian in the case of a doubly periodic perforated plane subject to periodic or non-periodic, non-compact perturbations. We also deal with the existence, number and position of spectral gaps in the case of the elasticity and piezoelectricity systems in waveguides with thin structures.