1 Elliptic operators, Dirichlet-to-Neumann maps and quasi boundary triples Page 1 1 Elliptic
operators, Dirichlet-to-Neumann maps and quasi boundary triples Jussi Behrndt and Matthias …

We consider “forward-backward” parabolic equations in the abstract form Jdψ/dx+ Lψ= 0, 0<
x≤∞, where J and L are operators in a Hilbert space H such that J= J*= J− 1, L= L*≥ 0, and …

We turn back to the well known problem of interpretation of the Schrodinger operator with
the pseudopotential being the first derivative of the Dirac function. We show that the problem …

This book is concerned with model representations theory of linear non-selfadjoint and non-
unitary operators, one of booming areas of functional analysis. This area owes its origin to …

Ordinary and partial differential operators with an indefinite weight function can be viewed
as bounded perturbations of non-negative operators in Krein spaces. Under the assumption …

Estimates on the non-real eigenvalues of regular indefinite Sturm–Liouville problems Page 1
Proceedings of the Royal Society of Edinburgh, 144A, 1113–1126, 2014 Estimates on the …

Based on continuity properties of the de Branges correspondence, we develop a new
approach to study the high-energy behavior of Weyl–Titchmarsh and spectral functions of 2× …

We consider one-dimensional Schrödinger-type operators in a bounded interval with non-
self-adjoint Robin-type boundary conditions. It is well known that such operators are …

We study a Sturm-Liouville expression with indefinite weight of the form $\mathrm {sgn}(-d^
2/dx^ 2+ V) $ on $\mathbb {R} $ and the non-real eigenvalues of an associated selfadjoint …

We study two problems. The first one is the similarity problem for the indefinite Sturm–
Liouville operator A=−(sgn x) dwdxdrdx acting in L w 2 (− b, b). It is assumed that w, r∈ L loc …