The essential spectrum of operator pencils with bounded coefficients in a Hilbert space is
studied. Sufficient conditions in terms of the operator coefficients of two pencils are derived …

We consider a non self-adjoint Laplacian on a directed graph with non symmetric edge
weights. We analyse spectral properties of this Laplacian under a Kirchhoff assumption …

We consider a non self-adjoint Laplacian on a directed graph with non symmetric edge
weights. We give sufficient conditions for this Laplacian to be sectorial. We introduce a …

In this paper, we construct a weighted geometric realization of the set of 2-simplexes and 3-
simplexes. On this weighted geometric realization, we create the Laplacian associated to 2 …

A new technique is developed for determining if the number of eigenvalues below the
essential spectrum of a singular elliptic differential operator is finite. A method is given for …

We consider a non self-adjoint Laplacian on a directed graph with non-symmetric weights
on edges. We give a criterion for the m-accretiveness and the m-sectoriality of this …

In this paper investigation is conducted of various essential spectra of minimal, maximal and
intermediate ordinary differential operators in scale of Lebesque spaces Lp (a1), 1 p 1 …

In this paper we study the asymptotic behaviour as ε→ 0 of the spectrum of the elliptic
operator A ε=− 1 b ε div (a ε∇) posed in a bounded domain Ω⊂ R n (n⩾ 2) subject to …

В первой части работы [1] получены общие результаты о различных существенных
спектрах некоторых классов обыкновенных дифференциальных операторов порядка п …

An inequality whose origins date to the work of GH Hardy is presented. This Hardy-type
inequality applies to derivatives of arbitrary order of functions whose domain is a subset of …