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Related papers: Some new classes of complex symmetric operators

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Let $\mathcal{H}$ be a separable complex Hilbert space. A conjugate-linear map $C:\mathcal{H}\to \mathcal{H}$ is called a conjugation if it is an involutive isometry. In this paper, we focus on the following interpolation problems: Let…

Functional Analysis · Mathematics 2024-11-27 Zouheir Amara

We present complete characterizations of Toeplitz operators that are complex symmetric. This follows as a by-product of characterizations of conjugations on Hilbert spaces. Notably, we prove that every conjugation admits a canonical…

Functional Analysis · Mathematics 2022-07-27 Sudip Ranjan Bhuia , Deepak Pradhan , Jaydeb Sarkar

We study the complex symmetric structure of weighted composition--differentiation operators of order $n $ on the weighted Bergman spaces $A_{\alpha}^2$ with respect to some conjugations. Then we provide some examples of these operators.

Functional Analysis · Mathematics 2021-01-14 Mahbube Moradi , Mahsa Fatehi

In this paper, we study complex symmetry of Toeplitz operators and block Toeplitz operators. In particular, we give a characterization of complex symmetric block Toeplitz operators with the special conjugation on the vector-valued Hardy…

Functional Analysis · Mathematics 2019-04-10 Dong-O Kang , Eungil Ko , Ji Eun Lee

In this paper we study the complex symmetry in the several variable Fock space by using the techniques of weighted composition operators and semigroups. We characterize unbounded weighted composition operators that are (real) complex…

Functional Analysis · Mathematics 2023-12-11 Pham Viet Hai , Pham Trong Tien

We call an operator algebra A {\em reversible} if A with reversed multiplication is also an abstract operator algebra (in the modern operator space sense). This class of operator algebras is intimately related to the {\em symmetric operator…

Operator Algebras · Mathematics 2025-11-24 David P. Blecher

We define a strong Morita-type equivalence $\sim _{\sigma \Delta }$ for operator algebras. We prove that $A\sim _{\sigma \Delta }B$ if and only if $A$ and $B$ are stably isomorphic. We also define a relation $\subset _{\sigma \Delta }$ for…

Operator Algebras · Mathematics 2018-12-12 G. K. Eleftherakis

We prove that the set of all complex symmetric operators on a separable, infinite-dimensional Hilbert space is not norm closed.

Functional Analysis · Mathematics 2011-03-31 Stephan Ramon Garcia , Daniel E. Poore

This paper aims to study reducible and irreducible approximation in the set $\textsl{CSO}$ of all complex symmetric operators on a separable, complex Hilbert space $\mathcal H$. When ${\rm dim} \mathcal H=\infty$, it is proved that both…

Functional Analysis · Mathematics 2018-12-13 Ting Liu , Jiayin Zhao , Sen Zhu

In this paper, we investigate when weighted composition operators acting on Dirichlet spaces $\mathcal{D}(\mathbb{B}_{N})$ are complex symmetric with respect to some special conjugations, and provide some characterizations of Hermitian…

Functional Analysis · Mathematics 2018-12-27 Xiao-He Hu , Zi-Cong Yang , Ze-Hua Zhou

We perform a classification of third order integrable systems of evolution equations with respect to higher symmetries. Applying it, we consider polynomial systems that are 0-homogeneous under a suitable weighting of variables with main…

Exactly Solvable and Integrable Systems · Physics 2014-04-22 Daryoush Talati

We present two novel results about Hilbert space operators which are nilpotent of order two. First, we prove that such operators are indestructible complex symmetric operators, in the sense that tensoring them with any operator yields a…

Functional Analysis · Mathematics 2012-07-17 Stephan Ramon Garcia , Bob Lutz , Dan Timotin

A new approach to normal operators in real Hilbert spaces is discussed, and a spectral representation is obtained, derived directly from the complex case. The results are then applied to quaternionic normal operators, regarded as a special…

Functional Analysis · Mathematics 2025-07-28 Florian-Horia Vasilescu

In this paper we show that a composition operator $C_\varphi$ cannot be complex symmetric on Hardy-Hilbert space $H^2(D)$ when $\varphi$ is an elliptic automorphism of order $3$ and not a rotation. This completes the project of finding all…

Functional Analysis · Mathematics 2016-08-02 Yong-Xin Gao , Ze-Hua Zhou

We investigate bicomplex Hamiltonian systems in the framework of an analogous version of the Schrodinger equation. Since in such a setting three different types of conjugates of bicomplex numbers appear, each is found to define in a natural…

Mathematical Physics · Physics 2015-11-23 Bijan Bagchi , Abhijit Banerjee

We consider the standard hypergeometric differential operator $D$ regarded as an operator on the complex plane $C$ and the complex conjugate operator $\overline D$. These operators formally commute and are formally adjoint one to another…

Functional Analysis · Mathematics 2021-05-25 Vladimir F. Molchanov , Yury A. Neretin

We investigate $\rho$-orthogonality and its local symmetry in the space of bounded linear operators. A characterization of Hilbert space operators with symmetric numerical range is established in terms of $\rho$-orthogonality. Further, we…

Functional Analysis · Mathematics 2025-12-15 Souvik Ghosh , Kallol Paul , Debmalya Sain

Using the unbounded picture of analytical K-homology, we associate a well-defined K-homology class to an unbounded symmetric operator satisfying certain mild technical conditions. We also establish an ``addition formula'' for the Dirac…

K-Theory and Homology · Mathematics 2007-05-23 Hela Bettaieb , Michel Matthey , Alain Valette

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

A semiregular operator on a Hilbert C^*-module, or equivalently, on the C^*-algebra of `compact' operators on it, is a closable densely defined operator whose adjoint is also densely defined. It is shown that for operators on extensions of…

Operator Algebras · Mathematics 2016-09-07 Arupkumar Pal