Picture of a sphere with binary code

Making Strathclyde research discoverable to the world...

The Strathprints institutional repository is a digital archive of University of Strathclyde research outputs. It exposes Strathclyde's world leading Open Access research to many of the world's leading resource discovery tools, and from there onto the screens of researchers around the world.

Explore Strathclyde Open Access research content

Variational principles for eigenvalues of block operator matrices

Langer, H. and Langer, M. and Tretter, Christiane (2002) Variational principles for eigenvalues of block operator matrices. Indiana University Mathematics Journal, 51 (6). pp. 1427-1460. ISSN 0022-2518

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

In this paper variational principles for block operator matrices are established which are based on functionals associated with the quadratic numerical range. These principles allow to characterize, e.g., eigenvalues in gaps of the essential spectrum and to derive two-sided eigenvalue estimates in terms of the spectral characteristics of the entries of the block operator matrix. The results are applied to a second order partial differential equation depending on the spectral parameter nonlinearly.