6 papers
Improved Lieb-Thirring type inequalities for non-selfadjoint Schrödinger operators
Sabine Bögli
We improve the Lieb-Thirring type inequalities by Demuth, Hansmann and Katriel (J. Funct. Anal. 2009) for Schrödinger operators with complex-valued potentials. Our result involves…
On Lieb--Thirring inequalities for one-dimensional non-self-adjoint Jacobi and Schr{\" o}dinger operators
Sabine Bögli, František Štampach
We study to what extent Lieb--Thirring inequalities are extendable from self-adjoint to general (possibly non-self-adjoint) Jacobi and Schrödinger operators. Namely, we prove the c…
Essential numerical ranges for linear operator pencils
Sabine Bögli, Marco Marletta
We introduce concepts of essential numerical range for the linear operator pencil . In contrast to the operator essential numerical range, the pencil essential numer…
The essential numerical range for unbounded linear operators
Sabine Bögli, Marco Marletta, Christiane Tretter
We introduce the concept of essential numerical range for unbounded Hilbert space operators and study its fundamental properties including possible equivalent char…
Local convergence of spectra and pseudospectra
Sabine Bögli
We prove local convergence results for the spectra and pseudospectra of sequences of linear operators acting in different Hilbert spaces and converging in generalised strong resolv…
Convergence of sequences of linear operators and their spectra
Sabine Bögli
We establish spectral convergence results of approximations of unbounded non-selfadjoint linear operators with compact resolvents by operators that converge in generalized strong r…