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Related papers: A note on positive $\mathcal{AN}$ operators

200 papers

In this paper we study commuting difference operators containing a shift operator with only positive degrees. We construct examples of such operators in the case of hyperelliptic spectral curves.

Algebraic Geometry · Mathematics 2018-10-26 Gulnara S. Mauleshova , Andrey E. Mironov

Given a self-adjoint operator H, a self-adjoint trace class operator V and a fixed Hilbert-Schmidt operator F with trivial kernel and co-kernel, using limiting absorption principle an explicit set of full Lebesgue measure is defined such…

Spectral Theory · Mathematics 2018-12-21 Nurulla Azamov

In this paper, we consider a two-variable operator function that includes two weighted spectral geometric means, and show fundamental properties of the operator function. Moreover, it satisfies the Ando-Hiai type inequality under some…

Functional Analysis · Mathematics 2025-12-30 Yuki Seo , Shuhei Wada , Takeaki Yamazaki

This paper is devoted to the generalization of the theory of total positivity. We say that a linear operator A in R^n is generalized totally positive (GTP), if its jth exterior power preserves a proper cone K_j in the corresponding space…

Spectral Theory · Mathematics 2013-01-17 O. Y. Kushel

For entire operators and entire operators in the generalized sense, we provide characterizations based on the spectra of their selfadjoint extensions. In order to obtain these spectral characterizations, we discuss the representation of a…

Mathematical Physics · Physics 2010-01-26 Luis O. Silva , Julio H. Toloza

In this article, we first prove the existence of an invariant subspace for a norm-attaining $\ast$-paranormal operator. Then give a representation for $\ast$-paranormal operators in the closure of absolutely norm-attaining operators and…

Functional Analysis · Mathematics 2023-02-03 G. Ramesh , Shanola S. Sequeira

This paper investigates composition operators and weighted composition operators on semi-Hilbert spaces induced by positive multiplication operators on \( L^2(\mu) \). Within the framework of \( A \)-adjoint operators, we characterize…

Functional Analysis · Mathematics 2025-08-08 Y. Estaremi , M. S. Al Ghafri

We consider abstract Banach spaces of analytic functions on general bounded domains that satisfy only a minimum number of axioms. We describe all invertible (equivalently, surjective) weighted composition operators acting on such spaces.…

Functional Analysis · Mathematics 2022-08-23 Alejandro Mas , Dragan Vukotić

We provide sufficient conditions on a Banach space $X$ in order that there exist norm attaining operators of rank at least two from $X$ into any Banach space of dimension at least two. For example, a rather weak such condition is the…

Functional Analysis · Mathematics 2019-10-01 Vladimir Kadets , Gines Lopez , Miguel Martin , Dirk Werner

Let $A$ be a separable, unital, simple C*-algebra with stable rank one. We show that every strictly positive, lower semicontinuous, affine function on the simplex of normalized quasitraces of $A$ is realized as the rank of an operator in…

Operator Algebras · Mathematics 2019-04-26 Hannes Thiel

It was recently proved that in some special cases asymmetric truncated Toeplitz operators can be characterized in terms of compressed shifts and rank-two operators of special form. In this paper we show that such characterizations hold in…

Functional Analysis · Mathematics 2020-07-29 Bartosz Łanucha , Małgorzata Michalska

A complete characterization of the similarity between two operator-valued multishifts with invertible operator weights is obtained purely in terms of operator weights. This generalizes several existing results of the unitary equivalence of…

Functional Analysis · Mathematics 2024-01-23 Soumitra Ghara , Surjit Kumar , Shailesh Trivedi

In this paper we study the norm-attainment of positive operators between Banach lattices. By considering an absolute version of James boundaries, we prove that: If $E$ is a reflexive Banach lattice whose order is given by a basis and $F$ is…

Functional Analysis · Mathematics 2025-07-03 José Lucas P. Luiz , Vinícius C. C. Miranda

In this note, we define a bounded variant on the Hilbert projective metric on an infinite dimensional space $E$ and study the contraction properties of the projective maps associated with positive linear operators on $E$. More precisely, we…

Functional Analysis · Mathematics 2025-02-07 Maxime Ligonnière

This paper studies the \(k^{th}-\)order slant Toeplitz and slant little Hankel operators on the weighted Bergman space \(\mathcal{A}_\alpha^2(\mathbb{D})\). These operators are constructed using a slant shift operator \(W_k\) composed with…

Functional Analysis · Mathematics 2025-07-10 Oinam Nilbir Singh , M. P. Singh , Thokchom Sonamani Singh

For self-adjoint Hankel operators of finite rank, we find an explicit formula for the total multiplicity of their negative and positive spectra. We also show that very strong perturbations, for example, a perturbation by the Carleman…

Functional Analysis · Mathematics 2013-04-10 D. R. Yafaev

The primary purpose of this paper is to investigate the question of invertibility of the sum of operators. The setting is bounded and unbounded linear operators. Some interesting examples and consequences are given. As an illustrative…

Functional Analysis · Mathematics 2018-10-04 Mohammed Hichem Mortad

In this paper, we show that the generalized Aluthge transforma- tions of a large class of operators (weighted conditional type operators) are normal. As a consequence, the operator MwEMu is p-hyponormal if and only if it is normal, and…

Functional Analysis · Mathematics 2013-10-14 Yousef Estaremi

A decomposition theorem for self-adjoint operators proved by Riesz and Lorch is extended to normal operators. This extension gives a new proof of the spectral theorem for unbounded normal operators.

Functional Analysis · Mathematics 2020-11-03 Katsukuni Nakagawa

We dominate non-integral singular operators by adapted sparse operators and derive optimal norm estimates in weighted spaces. Our assumptions on the operators are minimal and our result applies to an array of situations, whose prototype are…

Classical Analysis and ODEs · Mathematics 2016-08-03 Frédéric Bernicot , Dorothee Frey , Stefanie Petermichl