English
Related papers

Related papers: Flag structure for operators in the Cowen-Douglas …

200 papers

In the paper, we investigate weighted composition operators on Bergman spaces of a half-plane. We characterize weighted composition operators which are hermitian and those which are complex symmetric with respect to a family of…

Functional Analysis · Mathematics 2021-11-30 Pham Viet Hai , Osmar R. Severiano

Given a complex, separable Hilbert space $\mathcal{H}$, we characterize those operators for which $\| P T (I-P) \| = \| (I-P) T P \|$ for all orthogonal projections $P$ on $\mathcal{H}$. When $\mathcal{H}$ is finite-dimensional, we also…

Functional Analysis · Mathematics 2017-09-07 L. Livshits , G. MacDonald , L. W. Marcoux , H. Radjavi

We consider several differential operators on compact almost-complex, almost-Hermitian and almost-K\"ahler manifolds. We discuss Hodge Theory for these operators and a possible cohomological interpretation. We compare the associated spaces…

Differential Geometry · Mathematics 2020-03-09 Nicoletta Tardini , Adriano Tomassini

The purpose of this paper is to give an overview of the operator structure of frames, where the operator belongs to certain classes of linear operators and the element belongs to $H$. We discuss the size of the set of such elements. Also,…

Functional Analysis · Mathematics 2022-12-06 Jahangir Cheshmavar , Ayyaneh Dallaki

We prove that the flag kernel singular integral operators of Nagel-Ricci-Stein on a homogeneous group are bounded on the Lp spaces. The gradation associated with the kernels is the natural gradation of the underlying Lie algebra. Our main…

Functional Analysis · Mathematics 2011-11-02 Pawel Glowacki

We obtain a necessary and sufficient condition for a weighted composition operator to be co-isometric on a general weighted Hardy space of analytic functions in the unit disk whose reproducing kernel has the usual natural form. This turns…

Complex Variables · Mathematics 2021-07-14 María J. Martín , Alejandro Mas , Dragan Vukotić

We propose a notion of algebra of {\it twisted} chiral differential operators over algebraic manifolds with vanishing 1st Pontrjagin class. We show that such algebras possess families of modules depending on infinitely many complex…

Algebraic Geometry · Mathematics 2009-03-10 Tomoyuki Arakawa , Dmytro Chebotarov , Fyodor Malikov

We provide the definition and fundamental properties of algebraic elements with respect to an operator satisfying hypothesis (h). Furthermore, we analyze Hilbert modules using C_0-operators relative to a bounded finitely connected region…

Operator Algebras · Mathematics 2007-05-23 Yun-Su Kim

Relativizing an idea from multiplicity theory, we say that an element x of a von Neumann algebra M is n-divisible if (W*(x)' cap M) unitally contains a factor of type I_n. We decide the density of the n-divisible operators, for various n,…

Operator Algebras · Mathematics 2008-06-09 David Sherman

The hypergeometric type operators are shape invariant, and a factorization into a product of first order differential operators can be explicitly described in the general case. Some additional shape invariant operators depending on several…

Mathematical Physics · Physics 2009-02-24 Nicolae Cotfas

We show that a class of dynamical systems induces an associated operator system in Hilbert space. The dynamical systems are defined from a fixed finite-to-one mapping in a compact metric space, and the induced operators form a covariant…

Classical Analysis and ODEs · Mathematics 2009-09-29 Dorin Ervin Dutkay , Palle E. T. Jorgensen

In this note, we consider a class of composition operators on Lebesgue spaces with variable exponents over metric measure spaces. Taking advantage of the compatibility between the metric-measurable structure and the regularity properties of…

Functional Analysis · Mathematics 2025-02-04 Javier Henríquez-Amador , Carlos F. Álvarez

If an invertible linear dynamical systems is Li-York chaotic or other chaotic, what's about it's inverse dynamics? what's about it's adjoint dynamics? With this unresolved but basic problems, this paper will give a criterion for Lebesgue…

Functional Analysis · Mathematics 2015-04-07 Luo Lvlin , Hou Bingzhe

We classify all homogeneous odd (i.e., parity-reversing) Rota--Baxter operators of weight zero on the modified Witt-type Lie superalgebra $W = \langle L_m, G_n \rangle_{m,n\in\Z}$. Our classification shows that nontrivial such operators are…

Rings and Algebras · Mathematics 2025-12-05 Mohsen Ben Abdallah , Marwa Ennaceur

We study the homotopy theory of a certain type of diagram categories whose vertices are in variable categories with a functorial path, leading to a good calculation of the homotopy category in terms of cofibrant objects. The theory is…

Algebraic Topology · Mathematics 2016-10-04 Joana Cirici

In this paper, we study the homogeneous components of the Chern--Schwartz--MacPherson (CSM) classes of Schubert cells. We prove that, under suitable conditions, each such component is represented by an irreducible subvariety. In particular,…

Algebraic Geometry · Mathematics 2026-03-27 Yuxiang Liu , Artan Sheshmani , Shing-Tung Yau

Eigenfunctions and eigenvalues of the free magnetic Schr\"odinger operator, describing a spinless particle confined to an infinite layer of fixed width, are discussed in detail. The eigenfunctions are realized as an orthonormal basis of a…

Mathematical Physics · Physics 2009-11-10 K. Thirulogasanthar , Nasser Saad , Attila B. von Keviczky

Combining an old idea of Olver and Rosenau with the classification of second and third order homogeneous Hamiltonian operators we classify compatible trios of two-component homogeneous Hamiltonian operators. The trios yield pairs of…

Mathematical Physics · Physics 2018-02-19 P. Lorenzoni , A. Savoldi , R. Vitolo

In this paper we study the embedding problem of an operator into a strongly continuous semigroup. We obtain characterizations for some classes of operators, namely composition operators and analytic Toeplitz operators on the Hardy space…

Functional Analysis · Mathematics 2025-02-19 Isabelle Chalendar , Romain Lebreton

In this paper, we review the construction of the Dirac operator for graded affine Hecke algebras and calculate the Dirac cohomology of irreducible unitary modules for the graded Hecke algebra of gl(n).

Representation Theory · Mathematics 2012-07-13 Dan Barbasch , Dan Ciubotaru