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Related papers: Binormal, Complex Symmetric Operators

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We say that an operator $T \in B(H)$ is complex symmetric if there exists a conjugate-linear, isometric involution $C:H\to H$ so that $T = CT^*C$. We prove that binormal operators, operators that are algebraic of degree two (including all…

Functional Analysis · Mathematics 2009-07-23 Stephan Ramon Garcia , Warren R. Wogen

It is known that if an operator $T$ is complex symmetric then its Aluthge transform is also complex symmetric. This Note is devoted to showing that the Duggal transform doesn't inherit this property. For instance, we'll show that the Duggal…

Functional Analysis · Mathematics 2018-05-22 C. Benhida

We give necessary and sufficient conditions for a bounded operator defined between complex Hilbert spaces to be absolutely norm attaining. We discuss structure of such operators in the case of self-adjoint and normal operators separately.…

Spectral Theory · Mathematics 2018-01-09 G. Ramesh , D. Venku Naidu

In this paper, we introduce and study a new class of bounded linear operators on complex Hilbert spaces, which we call 2-C-normal operators. This class is inspired by and closely related to the notion of 2-normal operators, with additional…

Functional Analysis · Mathematics 2025-10-09 Messaoud Guesba , Ismail Lakehal , Sid Ahmed Ould Ahmed Mahmoud

In this paper we find all complex symmetric weighted composition operators with special conjugations. Then we give spectral properties of these complex symmetric weighted composition operators.

Functional Analysis · Mathematics 2018-04-10 Mahsa Fatehi

In this paper, we characterize absolute norm-attainability for compact hyponormal operators. We give necessary and sufficient conditions for a bounded linear compact hyponormal operator on an infinite dimensional complex Hilbert space to be…

Functional Analysis · Mathematics 2019-03-29 Benard Okelo

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

A new class of operators, larger than $C$-symmetric operators and different than normal one, named $C$--normal operators is introduced. Basic properties are given. Characterizations of this operators in finite dimensional spaces using a…

Functional Analysis · Mathematics 2020-01-01 Marek Ptak , Katarzyna Simik , Anna Wicher

The real theory of the Dunkl operators has been developed very extensively, while there still lacks the corresponding complex theory. In this paper we introduce the complex Dunkl operators for certain Coxeter groups. These complex Dunkl…

Complex Variables · Mathematics 2009-12-31 Guangbin Ren , Helmuth R. Malonek

In this paper we obtain necessary and sufficient conditions for a linear bounded operator in a Hilbert space $H$ to have a three-diagonal complex symmetric matrix with non-zero elements on the first sub-diagonal in an orthonormal basis in…

Functional Analysis · Mathematics 2011-02-17 Sergey M. Zagorodnyuk

Two necessary and sufficient conditions for an operator to be semi-normal are revealed. For a Volterra integration operator the set where the operator and its adjoint are metrically equal is described.

Spectral Theory · Mathematics 2015-02-03 L. Z. Gevorgyan

In this paper we find a sufficient condition under which the operator of bisexual population is contraction and show that this condition is not necessary.

Dynamical Systems · Mathematics 2012-04-03 N. N. Ganikhodjaev , U. U. Jamilov

Hyponormal operators are known to be among the most difficult operators to analyze. In this work, we focus on two finite types of hyponormal operators. The first type becomes analytic shifts, while the second type admits analytic models. A…

Functional Analysis · Mathematics 2026-02-27 Sneha B , Neeru Bala , Jaydeb Sarkar

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 and discuss some basic properties of the bicomplex analog of the classical Bargmann space. The explicit expression of the integral operator connecting the complex and bicomplex Bargmann spaces is also given. The corresponding…

Complex Variables · Mathematics 2019-07-26 Allal Ghanmi , Khalil Zine

In the present paper we introduce a concept of doubly stochastic quadratic operator. We prove necessary and sufficient conditions for doubly stochasticity of operator. Besides, we prove that the set of all doubly stochastic operators forms…

Functional Analysis · Mathematics 2008-02-11 Rasul Ganikhodzhaev , Farruh Shahidi

In this article, we give conditions guaranteeing the commutativity of a bounded self-adjoint operator with an unbounded closed symmetric operator.

Functional Analysis · Mathematics 2022-04-13 Souheyb Dehimi , Mohammed Hichem Mortad , Ahmed Bachir

An absolute continuity approach to quasinormality which relates the operator in question to the spectral measure of its modulus is developed. Algebraic characterizations of some classes of operators that emerged in this context are…

Functional Analysis · Mathematics 2013-10-15 Zenon Jan Jablonski , Il Bong Jung , Jan Stochel

Supersymmetry might be broken, in the real world, by anomalies that affect composite operators, while leaving the action supersymmetric. New constraint equations that govern the composite operators and their anomalies are examined. It is…

High Energy Physics - Theory · Physics 2007-05-23 John Dixon

We consider pairs of operators $A,B\in B(H)$, where $H$ is a Hilbert space, such that there exist a linear isometry $f$ from the span of $\{A,B\}$ into $\mathbb{C}^2$ mapping $A,B$ into orthonormal vectors. We prove some necessary…

Functional Analysis · Mathematics 2022-07-06 Bojan Magajna
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