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Related papers: Projection operators in the Weihrauch lattice

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We study the composition operators on an algebra of Dirichlet series, the analogue of the Wiener algebra of absolutely convergent Taylor series, which we call the Wiener-Dirichlet algebra. The central issue is to understand the connection…

Functional Analysis · Mathematics 2009-04-17 Frédéric Bayart , Catherine Finet , Daniel Li , Hervé Queffélec

We describe the shape of the symplectic Dirac operators on Hermitian symmetric spaces. For this, we consider these operators as families of operators that can be handled more easily than the original ones.

Symplectic Geometry · Mathematics 2008-04-24 Steffen Brasch , Katharina Habermann , Lutz Habermann

Leibniz algebras are non-skewsymmetric analogue of Lie algebras. In this paper, we consider weighted relative Rota-Baxter operators on Leibniz algebras. We define cohomology of such operators and as an application, we study their…

Representation Theory · Mathematics 2022-02-08 Apurba Das

In this note, we define a bounded variant on the Hilbert projective metric on an infinite dimensional space $E$ and study the contraction properties of the projective maps associated with positive linear operators on $E$. More precisely, we…

Functional Analysis · Mathematics 2025-02-07 Maxime Ligonnière

On an infinite set some closure operators are finitary (algebraic) while others are not. We can generalize this idea for a complete algebraic lattice letting the compact elements act as the finite sets. With this in mind, we will consider…

Rings and Algebras · Mathematics 2014-11-25 Martha Lee Hollist Kilpack

A new set of projection operators for three-dimensional models are constructed. Using these operators, an uncomplicated and easily handling algorithm for analysing the unitarity of the aforementioned systems is built up. Interestingly…

High Energy Physics - Theory · Physics 2012-12-04 A. Accioly , B. Pereira-Dias , C. A. Hernaski , J. A. Helayël-Neto

In this paper we study Weihrauch reducibility for multi-valued functions on represented spaces. We call the corresponding equivalence classes Weihrauch degrees and we show that the corresponding partial order induces a lower semi-lattice…

Logic · Mathematics 2011-01-07 Vasco Brattka , Guido Gherardi

Let $\phi$ be an analytic self-map and $u$ be a fixed analytic function on the open unit disk $D$ in the complex plane $\CC.$ The weighted composition operator is defined\break by \begin{equation*} uC_\phi f =u \cdot (f\circ \phi), f \in…

Complex Variables · Mathematics 2007-09-24 Songxiao Li , Stevo Stević

In this paper we provide an explicit expression for the proximity operator of a perspective of any proper lower semicontinuous convex function defined on a Hilbert space. Our computation enhances and generalizes known formulae for the case…

Optimization and Control · Mathematics 2024-11-13 Luis M. Briceño-Arias , Cristóbal Vivar-Vargas

Operator learning refers to the application of ideas from machine learning to approximate (typically nonlinear) operators mapping between Banach spaces of functions. Such operators often arise from physical models expressed in terms of…

Machine Learning · Computer Science 2024-02-27 Nikola B. Kovachki , Samuel Lanthaler , Andrew M. Stuart

In this paper, we investigate the properties of the Mordukhovich derivatives of the metric projection operator onto closed balls, closed and convex cylinders and positive cones in uniformly convex and uniformly smooth Banach spaces. We find…

Functional Analysis · Mathematics 2024-01-23 Jinlu Li

One approach to multivariate operator theory involves concepts and techniques from algebraic and complex geometry and is formulated in terms of Hilbert modules. In these notes we provide an introduction to this approach including many…

Functional Analysis · Mathematics 2007-11-28 Ronald G. Douglas

We characterize weak* closed unital vector spaces of operators on a Hilbert space $H$. More precisely, we first show that an operator system, which is the dual of an operator space, can be represented completely isometrically and weak*…

Operator Algebras · Mathematics 2014-02-26 David P. Blecher , Bojan Magajna

Invited talk at the International Symposium on Generalized Symmetries in Physics at the Arnold-Sommerfeld-Institute, Clausthal, Germany, July 26 -- July 29, 1993. This talk reviews results on the structure of algebras consisting of…

High Energy Physics - Theory · Physics 2009-09-25 Martin Schlichenmaier

In this article we investigate the action of (ramified and unramified) Hecke operators on automorphic forms for the function field of the projective line defined over a finite field and for the group GL_2. We first compute the dimension of…

Number Theory · Mathematics 2024-06-19 Roberto Alvarenga , Nans Bonnel

Motivated by Barr{\'\i}a-Halmos's \cite[Question 19]{barria1982asymptotic} and Halmos's \cite[Problem 237]{Halmos1978A}, we explore projections in Toeplitz algebra on the Hardy space. We show that the product of two Toeplitz (Hankel)…

Functional Analysis · Mathematics 2020-07-28 Hui Dan , Xuanhao Ding , Kunyu Guo , Yuanqi Sang

We study star operations for Iwahori-Hecke algebras and invariant hermitian forms for finite dimensional modules over (graded) affine Hecke algebras with a view towards a unitarity algorithm.

Representation Theory · Mathematics 2015-03-20 Dan Barbasch , Dan Ciubotaru

We consider various classes of bounded operators on the Fock space $F^2$ of Gaussian square integrable entire functions over the complex plane. These include Toeplitz (type) operators, weighted composition operators, singular integral…

Functional Analysis · Mathematics 2024-06-03 Wolfram Bauer , Robert Fulsche , Miguel Angel Rodriguez Rodriguez

This article is concerned with a geometric tool given by a pair of projector operators defined by almost product structures on finite dimensional manifolds, polarized by a distribution of constant rank and also endowed with some geometric…

Mathematical Physics · Physics 2011-10-11 Paulo Pitanga , Paulo R. Rodrigues

We investigate homogeneous third-order Hamiltonian operators of differential-geometric type. Based on the correspondence with quadratic line complexes, a complete list of such operators for two and three components is obtained.

Exactly Solvable and Integrable Systems · Physics 2015-06-18 Eugene V. Ferapontov , Maxim V. Pavlov , Raffaele F. Vitolo