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Related papers: Spectral synthesis for Banach Algebras II

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Let $A$ and $B$ be Banach algebras and let $B$ be an algebraic Banach $A-$bimodule. Then the $\ell^1-$direct sum $A\times B$ equipped with the multiplication $$(a_1,b_1)(a_2,b_2)=(a_1a_2,a_1\cdot b_2+b_1\cdot a_2+b_1b_2),~~ (a_1, a_2\in A,…

Functional Analysis · Mathematics 2016-06-16 Mohammad Ramezanpour

Este art\'iculo presenta como resultado principal la equivalencia entre, las categor\'ias de espacios topol\'ogicos Hausdorff-Compactos y la categor\'ia de las $C^*-$\'algebras conmutativas con unidad, producto de la ``traducci\'on'' en…

Category Theory · Mathematics 2024-09-25 Sebastian Alvarez Avendaño , Breitner Ocampo , Pedro Rizzo

Given two complex Banach spaces $X_1$ and $X_2$, a tensor product of $X_1$ and $X_2$, $X_1\tilde{\otimes}X_2$, in the sense of J. Eschmeier ([5]), and two finite tuples of commuting operators, $S=(S_1,\ldots ,S_n)$ and $T=(T_1,\ldots…

Functional Analysis · Mathematics 2016-05-24 Enrico Boasso

The topological Hochschild homology THH(R) of a commutative S-algebra (E_infty ring spectrum) R naturally has the structure of a commutative R-algebra in the strict sense, and of a Hopf algebra over R in the homotopy category. We show,…

Algebraic Topology · Mathematics 2014-10-01 Vigleik Angeltveit , John Rognes

Expository notes about spectral sequences, filtered spectra, and synthetic spectra. We focus on the $\tau$-formalism as it arises in filtered spectra.

Algebraic Topology · Mathematics 2025-12-24 Sven van Nigtevecht

We investigate the higher-dimensional amenability of tensor products $\A \ptp \B$ of Banach algebras $\A$ and $\B$. We prove that the weak bidimension $db_w$ of the tensor product $\A \ptp \B$ of Banach algebras $\A$ and $\B$ with bounded…

K-Theory and Homology · Mathematics 2009-04-30 Zinaida A. Lykova

Starting from the meaning of the conjugate of a complex Hilbert space, including a related application of the theorem of Fr\'{e}chet-Riesz (by which an analysis of semilinear operators can be reduced to - linear - operator theory) to a…

Functional Analysis · Mathematics 2026-01-05 Frank Oertel

Let $A$ and $B$ be Banach algebras, $\theta: A\to B$ be a continuous Banach algebra homomorphism and $I$ be a closed ideal in $B$. Then the direct sum of $A$ and $I$ with respect to $\theta$, denoted $A\bowtie^{\theta}I$, with a special…

Functional Analysis · Mathematics 2016-06-23 Hasan Pourmahmood Aghababa , Nematollah Shirmohammadi

For $C^*$-algebras $A$ and $B$, we prove the slice map conjecture for ideals in the operator space projective tensor product $A \hat\otimes B$. As an application, a characterization of prime ideals in the Banach $\ast$-algebra $A\hat\otimes…

Operator Algebras · Mathematics 2011-06-17 Ranjana Jain , Ajay Kumar

The completion $\overline{A}[\tau]$ of a locally convex *-algebra $A [ \tau ]$ with not jointly continuous multiplication is a *-vector space with partial multiplication $xy$ defined only for $x$ or $y \in A_{0}$, and it is called a…

Mathematical Physics · Physics 2009-04-07 F. Bagarello , A. Inoue , C. Trapani

The spectra of the second quantization and the symmetric second quantization of a strict Hilbert space contraction are computed explicitly and shown to coincide. As an application, we compute the spectrum of the nonsymmetric…

Mathematical Physics · Physics 2014-11-18 Jan van Neerven

Let $a$ and $b$ be elements of a semisimple, complex and unital Banach algebra $A$. Using subharmonic methods, we show that if the spectral containment $\sigma(ax)\subseteq\sigma(bx)$ holds for all $x\in A$, then $ax$ belongs to the…

Functional Analysis · Mathematics 2018-08-10 Rudi Brits , Francois Schulz , Cheick Toure

Several issues related to the practical synthesis of ternary sequences with specified spectra are addressed in this paper. Specifically, sequences with harmonic multiples of two and three suppressed are studied, given their relevance when…

Signal Processing · Electrical Eng. & Systems 2018-04-23 Alessio De Angelis , Johan Schoukens , Keith R. Godfrey , Paolo Carbone

The paper describes homomorphisms between Douglas algebras and some semisimple Banach algebras. The main tool is a result on the structure of the space $C(Z,\mathfrak M)$ of continuous mappings from a connected first-countable $T_1$ space…

Complex Variables · Mathematics 2022-09-14 Alexander Brudnyi

For $C^{*}$-algebras $A$ and $B$, the operator space projective tensor product $A\hat{\otimes}B$ and the Banach space projective tensor product $A\otimes_{\gamma}B$ are shown to be symmetric. We also show that $A\hat{\otimes}B$ is weakly…

Operator Algebras · Mathematics 2012-05-09 Ajay Kumar , Vandana Rajpal

We consider a family of measures $\mu$ supported in $\br^d$ and generated in the sense of Hutchinson by a finite family of affine transformations. It is known that interesting sub-families of these measures allow for an orthogonal basis in…

Functional Analysis · Mathematics 2010-01-27 Dorin Ervin Dutkay , Palle E. T. Jorgensen

A Banach space $X$ has \textit{property $(K)$}, whenever every weak* null sequence in the dual space admits a convex block subsequence $(f_{n})_{n=1}^\infty$ so that $\langle f_{n},x_{n}\rangle\to 0$ as $n\to \infty$ for every weakly null…

Functional Analysis · Mathematics 2021-02-02 Dongyang Chen , Tomasz Kania , Yingbin Ruan

We study two ways of summing an infinite family of noncommutative spectral triples. First, we propose a definition of the integration of spectral triples and give an example using algebras of Toeplitz operators acting on weighted Bergman…

Mathematical Physics · Physics 2016-11-18 Kevin Falk

In this dissertation I establish that a broad class of Banach *-algebras of infinite integral operators, defined by the property that the kernels of the elements of the algebras possess subexponential off-diagonal decay, is inverse closed…

Operator Algebras · Mathematics 2007-05-23 Scott Beaver

For a simple $C^*$-algebra $A$ and any other $C^*$-algebra $B$, it is proved that every closed ideal of $A \otimes^{\min} B$ is a product ideal if either $A$ is exact or $B$ is nuclear. Closed commutator of a closed ideal in a Banach…

Operator Algebras · Mathematics 2026-01-01 Ranjana Jain , Ved Prakash Gupta