48 research outputs found
Structured Perturbations of Semigroup Generators: Theory and Applications
Wir verwenden einen Störungsansatz, um lineare Operatoren und deren Spektral- und Generatoreigenschaften zu untersuchen. Dazu betrachten wir strukturierte Störungen, welche auch im Kontext linearer Systeme mit geschlossenem Feedback betrachtet wurden
Note on basic features of large time behaviour of heat kernels
Large time behaviour of heat semigroups (and more generally, of positive
selfadjoint semigroups) is studied. Convergence of the semigroup to the ground
state and of averaged logarithms of kernels to the ground state energy is shown
in the general framework of positivity improving selfadjoint semigroups. This
framework includes Laplacians on manifolds, metric graphs and discrete graphs.Comment: 24 page