We give a comprehensive treatment of Sturm-Liouville operators whose coefficients are
measures, including a full discussion of self-adjoint extensions and boundary conditions …

In this paper, we study the time persistence of superoscillations as the initial data of the time-
dependent Schrödinger equation with δ δ-and δ'δ′-potentials. It is shown that the …

We consider one-dimensional Dirac operator LP, U with Birkhoff regular boundary
conditions and summable potential P (x) on [0, π]. We introduce strongly and weakly regular …

Abstract We consider a Sturm–Liouville equation ℓ y:=-y''+ qy= λ y ℓ y:=-y′′+ qy= λ y on
the intervals (-a, 0)(-a, 0) and (0, b) with a, b> 0 a, b> 0 and q ∈ L^ 2 (-a, b) q∈ L 2 (-a, b) …

We consider symmetric operators of the form S:= A ⊗ I_ T+ I_ H ⊗ TS:= A⊗ IT+ IH⊗ T, where
A is symmetric and T= T^* T= T∗ is (in general) unbounded. Such operators naturally arise …

Abstract We consider a Sturm–Liouville equation ℓ y:=-y′′+ qy= λ y on the intervals (-a, 0)
and (0, b) with a, b> 0 and q∈ L 2 (-a, b). Boundary conditions y (-a) cos α= y′(-a) sin α, y …

We investigate absolutely continuous spectrum of generalized indefinite strings. By following
an approach of Deift and Killip, we establish stability of the absolutely continuous spectra of …

We prove an explicit weighted estimate for the semiclassical Schrödinger operator PD h2@
2 x CV. xI h/on L2. R/, with V. xI h/a finite signed measure, and where h> 0 is the …

We analyze a family of singular Schrödinger operators describing a Neumann waveguide
with a periodic array of singular traps of a $\delta\prime $ type. We show that in the limit …

The main goal of the paper is to present a new approach to the problem of continuous
dependence of solutions of differential or dynamic problems on their domains. This is of …