- W.-J. Beyn, W. Kleß, Vera Thümmler:
A continuation framework for invariant subspaces
and its application to traveling waves.
-
We present a continuation method for low-dimensional invariant subspaces of a
parametrized family of large and sparse matrices. Such matrices typically
occur when linearizing about branches of steady states in reaction-diffusion
equations.
Our continuation method provides bases of the invariant subspaces depending
smoothly on the parameter. From these we can compute the corresponding
eigenvalues efficiently.
The predictor and the corrector step are reduced to solving bordered matrix
equations of Sylvester type. For these equations we develop a bordered
version of the Bartels-Stewart algorithm.
The numerical techniques are used to study the stability problem for
traveling waves in two examples:
the Ginzburg-Landau and the FitzHugh-Nagumo system. In these cases there
always exists a simple or multiple eigenvalue zero while the remaining
eigenvalues determine the stability. We discuss the difficulties
of separating these critical eigenvalues from clusters of eigenvalues
that are generated by the essential spectrum of the continous problem.
preprint_30_99.ps (0.7MB, includes 2 illustrations)
DFG-Projekt Verbindungsorbits (Bielefeld)
DFG-Schwerpunktprogramm Dynamik (Berlin)
Thorsten Pampel, erstellt am 20.09.99
Fakultät für Mathematik |
Universität Bielefeld