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Related papers: Self-Adjointness of Deformed Unbounded Operators

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Warped convolutions of operators were recently introduced in the algebraic framework of quantum physics as a new constructive tool. It is shown here that these convolutions provide isometric representations of Rieffel's strict deformations…

Mathematical Physics · Physics 2011-04-22 Detlev Buchholz , Gandalf Lechner , Stephen J. Summers

We study various spectral theoretic aspects of non-self-adjoint operators. Specifically, we consider a class of factorable non-self-adjoint perturbations of a given unperturbed non-self-adjoint operator and provide an in-depth study of a…

Spectral Theory · Mathematics 2020-05-06 Fritz Gesztesy , Yuri Latushkin , Marius Mitrea , Maxim Zinchenko

We investigate the self-adjointness of the two dimensional Dirac operator with infinite mass boundary conditions on an unbounded domain with an infinite number of corners. We prove that if the domain has no concave corners, then the…

Analysis of PDEs · Mathematics 2024-08-06 Miguel Camarasa , Fabio Pizzichillo

We prove the Schr\"odinger operator with infinitely many point interactions in $\mathbb{R}^d$ $(d=1,2,3)$ is self-adjoint if the support of the interactions is decomposed into uniformly discrete clusters. Using this fact, we prove the…

Mathematical Physics · Physics 2019-11-15 Masahiro Kaminaga , Takuya Mine , Fumihiko Nakano

This paper is devoted to self-adjoint cyclically compact operators on Hilbert--Kaplansky module over a ring of bounded measurable functions. The spectral theorem for such a class of operators are given. We apply this result to partial…

Operator Algebras · Mathematics 2015-02-10 Farrukh Mukhamedov , Karimbergen Kudaybergenov

We prove quantitative bounds on the eigenvalues of non-selfadjoint unbounded operators obtained from selfadjoint operators by a perturbation that is relatively-Schatten. These bounds are applied to obtain new results on the distribution of…

Spectral Theory · Mathematics 2009-09-10 Michael Demuth , Marcel Hansmann , Guy Katriel

For a very general class of unbounded self-adjoint operator function we prove upper bounds for eigenvalues which lie within arbitrary gaps of the essential spectrum. These upper bounds are given by triple variations. Furthermore, we find…

Spectral Theory · Mathematics 2016-04-15 Matthias Langer , Michael Strauss

We investigate the properties of self-adjointness of a two-dimensional Dirac operator on an infinite sector with infinite mass boundary conditions and in presence of a Coulomb-type potential with the singularity placed on the vertex. In the…

Analysis of PDEs · Mathematics 2022-07-20 Biagio Cassano , Matteo Gallone , Fabio Pizzichillo

The Kubo-Ando theory deals with connections for positive bounded operators. On the other hand, in various analysis related to von Neumann algebras it is impossible to avoid unbounded operators. In this article we try to extend a notion of…

Operator Algebras · Mathematics 2021-02-03 Fumio Hiai , Hideki Kosaki

In this work we explore the self-adjointness of the GUP-modified momentum and Hamiltonian operators over different domains. In particular, we utilize the theorem by von-Newmann for symmetric operators in order to determine whether the…

High Energy Physics - Theory · Physics 2015-05-26 Venkat Balasubramanian , Saurya Das , Elias C. Vagenas

We study self-adjoint extensions of operators which are the product of the multiplication operator by an analytic function and the analytic continuation in a strip. We compute the deficiency indices of the product operator for a wide class…

Mathematical Physics · Physics 2015-08-27 Yoh Tanimoto

We consider first-order differential operators with locally bounded measurable coefficients on vector bundles with measurable coefficient metrics. Under a mild set of assumptions, we demonstrate the equivalence between the essential…

Functional Analysis · Mathematics 2019-07-04 Lashi Bandara , Hemanth Saratchandran

We investigate structural properties and normality criteria for certain classes of bounded linear operators on a Hilbert space. We show that an operator $T$ with polar decomposition $T = U|T|$ is self-adjoint if and only if $T$ is…

Functional Analysis · Mathematics 2026-02-24 Hranislav Stanković , Carlos Kubrusly

This is a continuation of our papers \cite{AP2} and \cite{AP3}. In those papers we obtained estimates for finite differences $(\D_Kf)(A)=f(A+K)-f(A)$ of the order 1 and $(\D_K^mf)(A)\df\sum\limits_{j=0}^m(-1)^{m-j}(m\j)f\big(A+jK\big)$ of…

Functional Analysis · Mathematics 2010-03-23 Aleksei Aleksandrov , Vladimir Peller

We prove quantitative bounds on the eigenvalues of non-selfadjoint bounded and unbounded operators. We use the perturbation determinant to reduce the problem to one of studying the zeroes of a holomorphic function.

Spectral Theory · Mathematics 2008-02-19 Michael Demuth , Marcel Hansmann , Guy Katriel

In this paper we define the deficiency indices of a closed symmetric right $\mathbb{H}$-linear operator and formulate a general theory of deficiency indices in a right quaternionic Hilbert space. This study provides a necessary and…

Mathematical Physics · Physics 2017-09-11 B. Muraleetharan , K. Thirulogasanthar

We consider a second order self-adjoint operator in a domain which can be bounded or unbounded. The boundary is partitioned into two parts with Dirichlet boundary condition on one of them, and Neumann condition on the other. We assume that…

Spectral Theory · Mathematics 2018-09-28 Denis Borisov , Ivan Veselic'

Noncommutative multivariable versions of weighted shifts arise naturally as `weighted' left creation operators acting on Fock space. We investigate the unital weak operator topology closed algebras they generate. The unweighted case yields…

Operator Algebras · Mathematics 2007-05-23 David W. Kribs

We develop the concept of operators in Hilbert spaces which are similar to their adjoints via antiunitary operators, the latter being not necessarily involutive. We discuss extension theory, refined polar and singular-value decompositions,…

Functional Analysis · Mathematics 2023-04-14 M. Cristina Câmara , David Krejcirik

Based on the recent construction of a self-adjoint momentum operator for a particle confined in a one-dimensional interval, we extend the construction to arbitrarily shaped regions in any number of dimensions. Different components of the…

Quantum Physics · Physics 2023-09-15 A. Mariani , U. -J. Wiese