SPECTRAL PROPERTIES OF FINITE-DIMENSIONAL WAVEGUIDE SYSTEMS


Çolakoğlu N., Lancaster P.

ELECTRONIC JOURNAL OF LINEAR ALGEBRA, vol.30, pp.670-692, 2015 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 30
  • Publication Date: 2015
  • Doi Number: 10.13001/1081-3810.2855
  • Journal Name: ELECTRONIC JOURNAL OF LINEAR ALGEBRA
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.670-692
  • Istanbul Technical University Affiliated: Yes

Abstract

This is a largely expository paper in which a finite dimensional model for gyroscopic/waveguiding systems is studied. Properties of the spectrum that play an important role when computing with such models are studied. The notion of "waveguide-type" is explored in this context. The main theorem provides a form of the central result (due to Abramov) concerning the existence of real spectrum for such systems. The roles of semisimple/defective eigenvalues are discussed, as well as the roles played by eigenvalue "types" (or "Krein signatures"). The theory is illustrated with examples.