Lampe, JörgJörgLampeVoß, HeinrichHeinrichVoß2021-12-152021-12-152021Electronic Transactions on Numerical Analysis 55 : 1-75 (2021)http://hdl.handle.net/11420/11302Variational principles are very powerful tools when studying self-adjoint linear operators on a Hilbert space H. Bounds for eigenvalues, comparison theorems, interlacing results, and monotonicity of eigenvalues can be proved easily with these characterizations, to name just a few. In this paper we consider generalizations of these principles to families of linear, self-adjoint operators depending continuously on a scalar in a real interval.en1068-96132021175AMLSFluid-solid interactionIterative projection methodsNonlinear eigenvalue problemQuantum dotsTotal least-squares problemsVariational characterizationViscoelastic dampingJournal Article10.1553/etna_vol55s1Other