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Related papers: Amalgamated direct sums of operator spaces

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In this work, a connection between some spectral properties of direct sum of operators in the direct sum of Hilbert spaces and its coordinate operators has been investigated.

Functional Analysis · Mathematics 2011-05-24 E. Otkun Cevik , Z. I. Ismailov

In this paper, structural properties of lower semi-frames in separable Hilbert spaces are explored with a focus on transformations under linear operators (may be unbounded). Also, the direct sum of lower semi-frames, providing necessary and…

Functional Analysis · Mathematics 2025-04-18 Hemalatha M , P. Sam Johnson , Harikrishnan P. K

We prove several singular value inequalities for sum and product of compact operators in Hilbert space. Some of our results generalize the previous inequalities for operators. Also, applications of some inequalities are given.

Functional Analysis · Mathematics 2015-10-02 A. Taghavi , V. Darvish , H. M. Nazari , S. S. Dragomir

Modular operads relevant to string theory can be equipped with an additional structure, coming from the connected sum of surfaces. Motivated by this example, we introduce a notion of connected sum for general modular operads. We show that a…

Quantum Algebra · Mathematics 2022-10-14 Martin Doubek , Branislav Jurčo , Lada Peksová , Ján Pulmann

We developpe a direct sum decomposition for n-dual spaces.

Functional Analysis · Mathematics 2007-05-23 Javier H. Guachalla

We study generalized sums of linear orders. These are binary operations that, given linear orders $A$ and $B$, return an order $A \oplus B$ that can be decomposed as an isomorphic copy of $A$ interleaved with a copy of $B$. We show that…

Logic · Mathematics 2025-12-17 Álvaro Díaz Ramos , Garrett Ervin , Saharon Shelah

We consider $\ell_p$-direct sums ($1\leq p<\infty$) and $c_0$-direct sums of countably many normed spaces and find the duals of these spaces. We characterize the support functionals of arbitrary elements in these spaces to characterize…

Functional Analysis · Mathematics 2023-09-26 Babhrubahan Bose

We prove new summability properties for multilinear operators on $\ell_p$ spaces. An important tool for this task is a better understanding of the interplay between almost summing and absolutely summing multilinear operators.

Functional Analysis · Mathematics 2014-04-07 O. Blasco , G. Botelho , D. Pellegrino , P. Rueda

Frames have been investigated frequently over the last few decades due to their valuable properties, which are desirable for various applications as well as interesting for theory. Some applications additionally require distributed…

Functional Analysis · Mathematics 2024-07-09 Lukas Köhldorfer , Peter Balazs

In this paper we study shorted operators relative to two different subspaces, for bounded operators on infinite dimensional Hilbert spaces. We define two notions of complementability in the sense of Ando for operators, and study the…

Functional Analysis · Mathematics 2007-05-23 Jorge Antezana , Gustavo Corach , Demetrio Stojanoff

We introduce mixed Morrey spaces and show some basic properties. These properties extend the classical ones. We investigate the boundedness in these spaces of the iterated maximal operator, the fractional integtral operator and singular…

Functional Analysis · Mathematics 2018-06-26 Toru Nogayama

In this paper, we observevd the amalgamated free probability of direct product of noncommutative probability spaces. We defined the amalgamated R-transforms, amalgamated moment series and the amalgamated boxed convolution. They maks us to…

Operator Algebras · Mathematics 2016-09-07 Ilwoo Cho

We study star product algebras of analytic functions for which the power series defining the products converge absolutely. Such algebras arise naturally in deformation quantization theory and in noncommutative quantum field theory. We…

Mathematical Physics · Physics 2013-12-24 Michael A. Soloviev

We consider a tensor product of two spaces of holomorphic functions on a Hermitian symmetric space of tube type. Then generically this is decomposed into a direct sum of irreducible subrepresentations. In this manuscript, we construct the…

Representation Theory · Mathematics 2026-03-24 Ryosuke Nakahama

On finite dimensional spaces, it is apparent that an operator is the product of two positive operators if and only if it is similar to a positive operator. Here, the class ${\mathcal L}^{+2}$ of bounded operators on separable infinite…

Functional Analysis · Mathematics 2021-01-27 Maximiliano Contino , Michael A. Dritschel , Alejandra Maestripieri , Stefania Marcantognini

We give a new proof of a characterization of the closeness of the range of a continuous linear operator and of the closeness of the sum of two closed vector subspaces of a Banach space. Then we state sufficient conditions for the closeness…

Functional Analysis · Mathematics 2015-10-06 Joël Blot , Philippe Cieutat

We discuss $\mathrm{L}^p$ fiber spaces which appear, e.g., as extrapolation spaces of unbounded multiplication operators which in turn are motivated, for instance, by non-autonomous evolution equations.

Functional Analysis · Mathematics 2019-11-20 Christian Budde , Retha Heymann

We show that a free product of a II_1-factor and a finite von Neumann algebra with amalgamation over a finite dimensional subalgebra is always a II_1-factor, and provide an algorithm for describing it in terms of free products (with…

Operator Algebras · Mathematics 2010-02-10 Ken Dykema

Several estimates for singular integrals, maximal functions and the spherical summation operator are given in the spaces $L^p_{\text{rad}}L^2_{\text{ang}}(\mathbb{R}^n)$, $n\geq 2$.

Classical Analysis and ODEs · Mathematics 2013-12-19 Antonio Córdoba

One-parameter generalizations of the logarithmic and exponential functions have been obtained as well as algebraic operators to retrieve extensivity. Analytical expressions for the successive applications of the sum or product operators on…

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