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Related papers: Amalgamated direct sums of operator spaces

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In this work, we introduce the concept of the direct integral of locally Hilbert spaces by generalizing the classical notion of a measure space to that of a locally measure space. We establish that the direct integral of a family of locally…

Functional Analysis · Mathematics 2025-08-07 Chaitanya J. Kulkarni , Santhosh Kumar Pamula

We give two general transformations that allows certain quite general basic hypergeometric multi-sums of arbitrary depth (sums that involve an arbitrary sequence $\{g(k)\}$), to be reduced to an infinite $q$-product times a single basic…

Number Theory · Mathematics 2019-01-09 James Mc Laughlin

We provide a list of equivalent conditions under which an additive operator acting on a space of smooth functions on a compact real interval is a multiple of the derivation.

Functional Analysis · Mathematics 2022-10-25 Włodzimierz Fechner , Aleksandra Świątczak

We study homological structure of the filtrations of the spaces of self-adjoint operators by the multiplicity of the ground state. We consider only operators acting in a finite dimensional complex or real Hilbert space but infinite…

Algebraic Topology · Mathematics 2011-10-14 Andrei Agrachev

Strongly irreducible operators can be considered as building blocks for bounded linear operators on complex separable Hilbert spaces. Many bounded linear operators can be written as direct sums of at most countably many strongly irreducible…

Functional Analysis · Mathematics 2012-11-28 Chunlan Jiang , Rui Shi

It is shown that each linear operator on a separable Hilbert space which generates a finite type I von Neumann algebra has, up to unitary equivalence, a unique representation as a direct integral of inflations of mutually unitary…

Functional Analysis · Mathematics 2017-05-26 Piotr Niemiec

In this paper, first we characterize closedness of range of the finite sum of weighted composition operators between different Lp-spaces. Then we discuss polar decomposition and invertibility of these operators.

Functional Analysis · Mathematics 2019-07-23 Saeedeh Shamsigamchi , Abolghasem Alishahi , Ali Ebadian

The aim of this article is to present two different primal-dual methods for solving structured monotone inclusions involving parallel sums of compositions of maximally monotone operators with linear bounded operators. By employing some…

Functional Analysis · Mathematics 2013-07-30 Radu Ioan Bot , Christopher Hendrich

We introduce certain linear positive operators and study some approximation properties of these operators in the space of functions, continuous on a compact set, of two variables. We also find the order of this approximation by using…

Classical Analysis and ODEs · Mathematics 2007-09-24 Fatma Tasdelen , Ali Olgun , Gulen Bascanbaz-Tunca

We generalize Bourgain's discretized sum-product theorem to matrix algebras.

Combinatorics · Mathematics 2017-10-18 Weikun He

Part I of the paper considered infinite orthogonal sums of regular subspaces in a Krein space (that is, of subspaces which are themselves Krein spaces). How precisely these sums should be defined and conditions for when such a sum is itself…

Functional Analysis · Mathematics 2026-02-26 Michael A. Dritschel , Alejandra Maestripieri , James Rovnyak

We investigate sufficient conditions for real-valued functions on product spaces to be bounded from above by sums or products of functions which depend only on points in the respective factors.

General Topology · Mathematics 2014-01-03 Stefan Born , Alexander Dirmeier

This is a survey on the amalgamated limit, a limit construction for complete Boolean algebras in iterated forcing theory, which generalizes both the direct limit and the two-step amalgamation. We focus in particular on examples of the…

Logic · Mathematics 2023-02-13 Joerg Brendle

Let $1\leq p,q < \infty$ and $1\leq r \leq \infty$. We show that the direct sum of mixed norm Hardy spaces $\big(\sum_n H^p_n(H^q_n)\big)_r$ and the sum of their dual spaces $\big(\sum_n H^p_n(H^q_n)^*\big)_r$ are both primary. We do so by…

Functional Analysis · Mathematics 2018-10-03 Richard Lechner

We propose an algorithm for computing the proximity operator of a sum of composite convex functions in Hilbert spaces and investigate its asymptotic behavior. Applications to best approximation and image recovery are described.

Optimization and Control · Mathematics 2010-07-22 Patrick L. Combettes , Dinh Dung , Bang Cong Vu

Motivated by a question in Schubert calculus, we study the interplay of quasisymmetric polynomials with the divided symmetrization operator, which was introduced by Postnikov in the context of volume polynomials of permutahedra. Divided…

Combinatorics · Mathematics 2020-05-05 Philippe Nadeau , Vasu Tewari

Given a LHS (Lattice of Hilbert spaces) $V_J$ and a symmetric operator $A$ in $V_J$, in the sense of partial inner product spaces, we define a generalized resolvent for $A$ and study the corresponding spectral properties. In particular, we…

Mathematical Physics · Physics 2016-10-24 Jean-Pierre Antoine , Camillo Trapani

Here we generalize the concept of spatial tensor product, introduced by Skeide, of two product systems via a pair of normalized units. This new notion is called amalgamated tensor product of product systems, and now the amalgamation can be…

Operator Algebras · Mathematics 2014-05-16 B. V. Rajarama Bhat , Mithun Mukherjee

This work is a contribution to the area of Strict Quantization (in the sense of Rieffel) in the presence of curvature and non-Abelian group actions. More precisely, we use geometry to obtain explicit oscillatory integral formulae for…

Quantum Algebra · Mathematics 2007-05-23 Pierre Bieliavsky

One can find lists of whole numbers having equal sum and product. We call such a creature a bioperational multiset. No one seems to have seriously studied them in areas outside whole numbers such as the rationals, Gaussian integers, or…

Rings and Algebras · Mathematics 2019-08-12 Onno M. Cain