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Related papers: Agler-Commutant Lifting on an Annulus

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The motivation behind this paper is threefold. Firstly, to study, characterize and realize operator concavity along with its applications to operator monotonicity of free functions on operator domains that are not assumed to be matrix…

Functional Analysis · Mathematics 2020-09-29 Miklós Pálfia

Paragrassmann algebras are given a sesquilinear form for which one subalgebra becomes a Hilbert space known as the Segal-Bargmann space. This Hilbert space as well as the ambient space of the paragrassmann algebra itself are shown to have…

Mathematical Physics · Physics 2012-05-22 Stephen Bruce Sontz

Commutators of bilinear Calder\'on-Zygmund operators and multiplication by functions in a certain subspace of the space of functions of bounded mean oscillations are shown to be compact on appropriate products of weighted Lebesgue spaces.

Classical Analysis and ODEs · Mathematics 2013-10-24 Árpád Bényi , Wendolín Damián , Kabe Moen , Rodolfo H. Torres

A new functional model for pairs of commuting isometries is described. Intertwining operators between such models are then studied in order to approach the classification of invariant subspaces of such pairs.

Spectral Theory · Mathematics 2008-05-27 H. Bercovici , R. G. Douglas , C. Foias

Let R be a polynomial ring in r variables and D a dual ring upon which R acts as partial differential operators (classical apolarity). For a type two graded level Artinian algebras A=R/I, of socle degree j we consider the family of Artinian…

Commutative Algebra · Mathematics 2007-05-23 Anthony Iarrobino

By working with all collection of all the Sarason Hilbert Hardy spaces for the annulus algebra an improvement to the results of Aryana and Clancey on eigenvalues of self adjoint Toeplitz operators on an annulus is obtained. The ideas are…

Functional Analysis · Mathematics 2013-08-28 Adam Broschinski

We study the generalization of $m$-isometries and $m$-contractions (for positive integers $m$) to what we call $a$-isometries and $a$-contractions for positive real numbers $a$. We show that any Hilbert space operator, satisfying an…

Functional Analysis · Mathematics 2020-07-17 Luciano Abadias , Glenier Bello , Dmitry Yakubovich

In this paper, we use a new method to solve a long-standing problem. More specifically, we show that the Beurling-type theorem holds in the Bergman space $A^2_\alpha(D)$ for any $-1<\alpha < +\infty$. That is, every invariant subspace $H$…

Functional Analysis · Mathematics 2022-07-27 Junfeng Liu

This article describes Hilbert spaces contractively contained in certain reproducing kernel Hilbert spaces of analytic functions on the open unit disc which are nearly invariant under division by an inner function. We extend Hitt's theorem…

Functional Analysis · Mathematics 2025-02-19 Arshad Khan , Sneh Lata , Dinesh Singh

We study the zero product problem of Toeplitz operators on the Hardy space and Bergman space over an annulus. Assuming a condition on the Fourier expansion of the symbols, we show that there are no zero divisors in the class of Toeplitz…

Functional Analysis · Mathematics 2025-04-24 Susmita Das , E. K. Narayanan

A commuting pair of operators (S, P) on a Hilbert space H is said to be a Gamma-contraction if the symmetrized bidisc is a spectral set of the tuple (S, P). In this paper we develop some operator theory inspired by Agler and Young's results…

Functional Analysis · Mathematics 2014-07-17 Jaydeb Sarkar

The possibility of testing spatial noncommutativity via a Penning trap is explored. The case of both space-space and momentum-momentum noncommuting is considered. Spatial noncommutativity leads to the spectrum of the orbital angular…

High Energy Physics - Phenomenology · Physics 2007-05-23 Jian-Zu Zhang

Matrix valued inner functions on the bidisk have a number of natural subspaces of the Hardy space on the torus associated to them. We study their relationship to Agler decompositions, regularity up to the boundary, and restriction maps into…

Functional Analysis · Mathematics 2017-01-20 Kelly Bickel , Greg Knese

This paper provides a homotopical version of the adjoint lifting theorem in category theory, allowing for Quillen equivalences to be lifted from monoidal model categories to categories of algebras over colored operads. The generality of our…

Algebraic Topology · Mathematics 2020-06-16 David White , Donald Yau

Motivated by Ball, Li, Timotin and Trent's Schur-Agler class version of commutant lifting theorem, we introduce a class, denoted by $\mathcal{P}_n(\mathcal{H})$, of $n$-tuples of commuting contractions on a Hilbert space $\mathcal{H}$. We…

Functional Analysis · Mathematics 2020-04-07 Sibaprasad Barik , B. Krishna Das , Jaydeb Sarkar

This paper is a follow-up contribution to our work [20] where we discussed some invariant subspace results for contractions on Hilbert spaces. Here we extend the results of [20] to the context of n-tuples of bounded linear operators on…

Functional Analysis · Mathematics 2015-02-20 Jaydeb Sarkar

We prove a Montel theorem for Hilbert space valued functions, and a non-commutative version of this theorem, by composing with unitaries to achieve convergence.

Functional Analysis · Mathematics 2017-06-20 Jim Agler , John E. McCarthy

We study analytic models of operators of class $C_{\cdot 0}$ with natural positivity assumptions. In particular, we prove that for an $m$-hypercontraction $T \in C_{\cdot 0}$ on a Hilbert space $\mathcal{H}$, there exists a Hilbert space…

Functional Analysis · Mathematics 2016-02-26 Monojit Bhattacharjee , Jaydeb Sarkar

We show that every function in a reproducing kernel Hilbert space with a normalized complete Pick kernel is the quotient of a multiplier and a cyclic multiplier. This extends a theorem of Alpay, Bolotnikov and Kaptano\u{g}lu. We explore…

Functional Analysis · Mathematics 2020-09-23 Alexandru Aleman , Michael Hartz , John E. McCarthy , Stefan Richter

Motivated by the theory of weighted shifts on directed trees and its multivariable counterpart, we address the question of identifying commutant and reflexivity of the multiplication $d$-tuple $\mathscr M_z$ on a reproducing kernel Hilbert…

Functional Analysis · Mathematics 2018-06-06 Sameer Chavan , Shubhankar Podder , Shailesh Trivedi