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Related papers: H${}^2$ Spaces of Non-Commutative Functions

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In a recent paper, we introduced and studied the class of admissible noncommutative domains $D_{g^{-1}}(H)$ in $B(H)^n$ associated with admissible free holomorphic functions $g$ in noncommutative indeterminates $Z_1,\ldots, Z_n$. Each such…

Functional Analysis · Mathematics 2024-04-16 Gelu Popescu

We study properties of inner and outer functions in the Hardy space of the quaternionic unit ball. In particular, we give sufficient conditions as well as necessary ones for functions to be inner or outer.

Complex Variables · Mathematics 2019-03-06 Alessandro Monguzzi , Giulia Sarfatti , Daniel Seco

We introduce a ring of noncommutative shifted symmetric functions based on an integer-indexed sequence of shift parameters. Using generating series and quasideterminants, this multiparameter approach produces deformations of the ring of…

Rings and Algebras · Mathematics 2023-05-04 Robert Laugwitz , Vladimir Retakh

The goal of this paper is to study the structure of noncommutative weighted shifts, their properties, and to understand their role as models (up to similarity) for $n$-tuples of operators on Hilbert spaces as well as their implications to…

Functional Analysis · Mathematics 2024-04-16 Gelu Popescu

Like its precursor this paper is concerned with the Hopf algebra of noncommutative symmetric functions and its graded dual, the Hopf algebra of quasisymmetric functions. It complements and extends the previous paper but is also…

Quantum Algebra · Mathematics 2007-05-23 Michiel Hazewinkel

In analogy with conventional quantum mechanics, non-commutative quantum mechanics is formulated as a quantum system on the Hilbert space of Hilbert-Schmidt operators acting on non-commutative configuration space. It is argued that the…

Mathematical Physics · Physics 2009-04-17 F G Scholtz , L Gouba , A Hafver , C M Rohwer

We completely describe the boundedness of the Volterra type operator $J_ g$ between Hardy spaces in the unit ball of $\Cn$. The proof of the one dimensional case used tools, such as the strong factorization for Hardy spaces, that are not…

Complex Variables · Mathematics 2013-12-04 Jordi Pau

We generalise the result of Berger and Shaw the trace formula for Hardy Hilbert space to a larger class of rotation invariant Hilbert function spaces on the unit disk. We also demonstrate many meaningful examples of these Hilbert spaces by…

Functional Analysis · Mathematics 2025-08-06 Nathan Parker

We argue that there should exist a "noncommutative Fourier transform" which should identify functions of noncommutative variables (say, of matrices of indeterminate size) and ordinary functions or measures on the space of paths. Some…

Quantum Algebra · Mathematics 2007-05-23 M. Kapranov

In this paper we study noncommutative domains D_f in B(H)^n, generated by positive regular free holomorphic functions f, where B(H) is the algebra of all bounded linear operators on a Hilbert space H.

Functional Analysis · Mathematics 2009-02-04 Gelu Popescu

We give a new proof that bounded non-commutative functions on polynomial polyhedra can be represented by a realization formula, a generalization of the transfer function realization formula for bounded analytic functions on the unit disk.

Functional Analysis · Mathematics 2019-08-15 Jim Agler , John E. McCarthy

Some identities for noncommutative perspectives of operator monotone functions in Hilbert spaces aregiven. Applications for weighted operator geometric mean and relative operator entropy are also provided.

Functional Analysis · Mathematics 2020-09-02 Silvestru Sever Dragomir

We present some old and new results on a class of invariant spaces of holomorphic functions on symmetric domains, both in their circular bounded realizations and in their unbounded realizations as Siegel domains of type II. These spaces…

Complex Variables · Mathematics 2026-04-21 Mattia Calzi

We study Hardy spaces $\mathcal{H}^p$, $0<p<\infty$ for quasiregular mappings on the unit ball $B$ in $\mathbb{R}^n$ which satisfy appropriate growth and multiplicity conditions. Under these conditions we recover several classical results…

Complex Variables · Mathematics 2023-09-25 Tomasz Adamowicz , María J. González

We give a definition of noncommutative finite-dimensional Euclidean spaces $\mathbb R^n$. We then remind our definition of noncommutative products of Euclidean spaces $\mathbb R^{N_1}$ and $\mathbb R^{N_2}$ which produces noncommutative…

Quantum Algebra · Mathematics 2018-06-13 Michel Dubois-Violette , Giovanni Landi

In this paper we extend the standard differential geometric theory of Hamiltonian dynamics to noncommutative spaces, beginning with symplectic forms. Derivations on the algebra are used instead of vector fields, and interior products and…

Quantum Algebra · Mathematics 2007-05-23 Edwin J. Beggs

The fundamental quasisymmetric functions in superspace are a generalization of the fundamental quasisymmetric functions involving anticommuting variables. We obtain the action of the product, coproduct, and antipode on the fundamental…

Combinatorics · Mathematics 2024-11-21 Susanna Fishel , Jessica Gatica , Luc Lapointe , Maria Elena Pinto

The main themes of this survey are as follows: (a) the canonical (Riesz--Nevanlinna) factorization in various classes of analytic functions on the disk that are smooth up to its boundary, and (b) model subspaces (i.e., invariant subspaces…

Complex Variables · Mathematics 2019-09-04 Konstantin M. Dyakonov

The standard lore in noncommutative physics is the use of first order variational description of a dynamical system to probe the space noncommutativity and its consequences in the dynamics in phase space. As the ultimate goal is to…

High Energy Physics - Theory · Physics 2008-11-26 Ignacio Cortese , J. Antonio Garcia

We prove that a random function in the Hardy space $H^2$ is a non-cyclic vector for the backward shift operator almost surely. The question of existence of a local pseudocontinuation for a random analytic function is also studied.

Complex Variables · Mathematics 2007-05-23 Evgeny Abakumov , Alexei Poltoratski