English
Related papers

Related papers: Compact $AC(\sigma)$ operators

200 papers

We describe $\sigma$-matching, interchangeable and, as a consequence, totally compatible products on some classes of associative algebras, including unital algebras, the semigroup algebras of rectangular bands, algebras with enough…

Rings and Algebras · Mathematics 2025-10-22 Mykola Khrypchenko

In this paper we determine a sufficient condition for the quasinilpotency of a commutator of compact operators via block-tridiagonal matrix form associated with a compact operator. We also prove that every compact operator is unitarily…

Functional Analysis · Mathematics 2024-01-31 Sasmita Patnaik , Rahul Sethi

In this paper we develop the functional calculus for elliptic operators on compact Lie groups without the assumption that the operator is a classical pseudo-differential operator. Consequently, we provide a symbolic descriptions of complex…

Functional Analysis · Mathematics 2014-05-15 Michael Ruzhansky , Jens Wirth

We establish compactness estimates for $\bar{\partial}_{M}$ on a compact pseudoconvex CR-submanifold $M$ of $\mathbb{C}^{n}$ of hypersurface type that satisfies the (analogue of the) geometric sufficient conditions for compactness of the…

Complex Variables · Mathematics 2010-10-26 Samangi Munasinghe , Emil J. Straube

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

In this paper, we define in an intrinsic way operators on a compact Lie group by means of symbols using the representations of the group. The main purpose is to show that these operators form a symbolic pseudo-differential calculus which…

Representation Theory · Mathematics 2015-03-17 Veronique Fischer

In the framework of one dimensional potential scattering we prove that, modulo a compact term, the wave operators can be written in terms of a universal operator and of the scattering operator. The universal operator is related to the one…

Mathematical Physics · Physics 2008-08-12 Johannes Kellendonk , Serge Richard

Given a (reduced) locally compact quantum group $A$, we can consider the convolution algebra $L^1(A)$ (which can be identified as the predual of the von Neumann algebra form of $A$). It is conjectured that $L^1(A)$ is operator biprojective…

Operator Algebras · Mathematics 2010-03-16 Matthew Daws

We define an equivariant index of Spin$^c$-Dirac operators on possibly noncompact manifolds, acted on by compact, connected Lie groups. The main result in this paper is that the index decomposes into irreducible representations according to…

Differential Geometry · Mathematics 2017-10-18 Peter Hochs , Yanli Song

This paper provides a complete characterization of quasicontractive groups and analytic $C_0$-semigroups on Hardy and Dirichlet space on the unit disc with a prescribed generator of the form $Af=Gf'$. In the analytic case we also give a…

Functional Analysis · Mathematics 2016-01-13 C. Avicou , I. Chalendar , J. R. Partington

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

The Casimir operators of a Lie algebra are in one-to-one correspondence with the symmetric invariant tensors of the algebra. There is an infinite family of Casimir operators whose members are expressible in terms of a number of primitive…

Mathematical Physics · Physics 2009-10-31 A. J. Mountain

In this paper, we give some results concerning atomic decompositions for operators on reproducing kernel Hilbert spaces, using frame theory techniques. We provide also generalizations for atomic decompositions of some theorems for…

Functional Analysis · Mathematics 2014-02-03 Laura Gavruta

Composition operators with analytic symbols on some reproducing kernel Hilbert spaces of entire functions on a complex Hilbert space are studied. The questions of their boundedness, seminormality and positivity are investigated. It is…

Functional Analysis · Mathematics 2016-10-17 Jan Stochel , Jerzy B. Stochel

Recent work by several authors has revealed the existence of many unexpected classes of normal weighted composition operators. On the other hand, it is known that every normal operator is a complex symmetric operator. We therefore undertake…

Functional Analysis · Mathematics 2012-05-22 Stephan Ramon Garcia , Christopher Hammond

We prove that local observables of the set of GHZ operators for particles of spin higher than 1/2 reduce to direct sums of the spin 1/2 operators $\sigma_x$, $\sigma_y$ and, therefore, no new contradictions with local realism arise by…

Quantum Physics · Physics 2007-05-23 J. Savinien , J. Taron , R. Tarrach

Fractional difference sequence spaces have been studied in the literature recently. In this work, some identities or estimates for the operator norms and the Hausdorff measures of noncompactness of certain operators on some difference…

Functional Analysis · Mathematics 2019-02-22 Faruk Özger

In this paper we investigate boundedness, polar decomposition and spectral decomposition of weighted conditional expectation type operators on L^2(\Sigma).

Functional Analysis · Mathematics 2013-02-05 Yousef Estaremi

In this paper we give the answers to two open questions on complex symmetric composition operators. By doing this, we give a complete description of complex symmetric composition operators whose symbols are linear fractional.

Functional Analysis · Mathematics 2017-01-31 Yong-Xin Gao , Ze-Hua Zhou

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