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In this paper, using the recently discovered notion of the $S$-spectrum, we prove the spectral theorem for a bounded or unbounded normal operator on a Clifford module (i.e., a two-sided Hilbert module over a Clifford algebra based on units…

Functional Analysis · Mathematics 2021-12-13 Fabrizio Colombo , David P. Kimsey

Let $\mathcal{H}$ be a right quaternionic Hilbert space and let $T$ be a quaternionic normal operator with the domain $\mathcal{D}(T) \subset \mathcal{H}$. Then for a fixed unit imaginary quaternion $m$, there exists a Hilbert basis…

Spectral Theory · Mathematics 2017-11-03 G. Ramesh , P. Santhosh Kumar

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

In this work, an operator superquadratic function (in operator sense) for positive Hilbert space operators is defined. Several examples with some important properties together with some observations which are related to the operator…

Functional Analysis · Mathematics 2019-12-17 M. W. Alomari

We provide a brief survey of a certain algebra of operators on symmetric polynomials, and collect a number of previously known results in the field.

Combinatorics · Mathematics 2013-10-15 Andrei Negut

We study differential operators associated with families of polynomials orthonormal with respect to certain measures. These operators, when applied to the Fourier transforms of such measures, produce basis functions for expansions of…

Classical Analysis and ODEs · Mathematics 2025-12-03 Aleksandar Ignjatovic

In the present paper, we introduce three neural network operators of convolution type activated by symmetrized, deformed and parametrized B-generalized logistic function. We deal with the approximation properties of these operators to the…

Numerical Analysis · Mathematics 2025-03-31 Asiye Arif , Tuğba Yurdakadim

We prove new spectral enclosures for the non-real spectrum of a class of $2\times2$ block operator matrices with self-adjoint operators $A$ and $D$ on the diagonal and operators $B$ and $-B^*$ as off-diagonal entries. One of our main…

Spectral Theory · Mathematics 2020-06-02 Juan Giribet , Matthias Langer , Francisco Martínez Pería , Friedrich Philipp , Carsten Trunk

This paper presents a bicomplex version of the Spectral Decomposition Theorem on infinite dimensional bicomplex Hilbert spaces. In the process, the ideas of bounded linear operators, orthogonal complements and compact operators on bicomplex…

Functional Analysis · Mathematics 2013-01-25 Kuldeep Singh Charak , Ravinder Kumar , Dominic Rochon

Jacobi operators appear as kinetic operators of several classes of noncommutative field theories (NCFT) considered recently. This paper deals with the case of bounded Jacobi operators. A set of tools mainly issued from operator and spectral…

Mathematical Physics · Physics 2015-08-07 Antoine Géré , Jean-Christophe Wallet

A method of generating differential operators is used to solve the spectral problem for a generalisation of the Sylvester-Kac matrix. As a by-product, we find a linear differential operator with polynomial coefficients of the first order…

Classical Analysis and ODEs · Mathematics 2021-07-12 Alexander Dyachenko , Mikhail Tyaglov

We present some properties of orthogonality and relate them with support disjoint and norm inequalities in p Schatten ideals. In addition, we investigate the problem of characterization of norm parallelism for bounded linear operators. We…

Functional Analysis · Mathematics 2021-07-23 T. Bottazzi , C. Conde , M. S. Moslehian , P. Wojcik , A. Zamani

We prove a T(1) theorem for bilinear singular integral operators (trilinear forms) with a one-dimensional modulation symmetry.

Classical Analysis and ODEs · Mathematics 2007-10-05 Arpad Benyi , Ciprian Demeter , Andrea R. Nahmod , Christoph M. Thiele , Rodolfo H. Torres , Francisco Villarroya

We construct supersymmetric irregular vertex operators of arbitrary rank, appearing in the colliding limit of primary fields. We find that the structure of the supersymmetric irregular vertices differs significantly from the bosonic case:…

High Energy Physics - Theory · Physics 2016-11-02 Dimitri Polyakov , Chaiho Rim

We shall say that a densely defined closed operator $T$ on a Hilbert space is balanced if $\cD(T)=\cD(T^*)$. Balanced operators are described in terms of their phase operators abnd their moduli. Examples of balanced operators are developed.…

Functional Analysis · Mathematics 2021-03-15 Konrad Schmüdgen

We construct a new representation for two- and three-point correlators of operators from sl(2) sector of planar N = 4 SYM. The spin and twist of operators are arbitrary. We start with the correlation function of light-ray operators and…

High Energy Physics - Theory · Physics 2015-06-18 Evgeny Sobko

A unital $C^*$-algebra is called $N$-subhomogeneous if its irreducible representations are finite dimensional with dimension at most $N$. We extend this notion to operator systems, replacing irreducible representations by boundary…

Operator Algebras · Mathematics 2023-02-10 Ran Kiri

Let $A$ be a unital Banach algebra. We give a characterization of the left Banach $A$-modules $X$ for which there exists a commutative unital $C^*$-algebra $C(K)$, a linear isometry $i\colon X\to C(K)$, and a contractive unital homomorphism…

Operator Algebras · Mathematics 2007-05-23 David P. Blecher , Christian Le Merdy

We introduce a trilinear functional of differential one-forms for a finitely summable regular spectral triple with a noncommutative residue. We demonstrate that for a canonical spectral triple over a closed spin manifold it recovers the…

Quantum Algebra · Mathematics 2024-08-22 Ludwik Dąbrowski , Andrzej Sitarz , Paweł Zalecki

We give a description of the field of rational natural differential invariants for a class of nonlinear differential operators of the third order on a two dimensional manifold and show their application to the equivalence problem of such…

Mathematical Physics · Physics 2022-12-07 Valentin Lychagin , Valeriy Yumaguzhin