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Related papers: Arveson's extension theorem in *-algebras

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We answer, by counterexample, several open questions concerning algebras of operators on a Hilbert space. The answers add further weight to the thesis that, for many purposes, such algebras ought to be studied in the framework of operator…

Operator Algebras · Mathematics 2007-05-23 David P. Blecher , Bojan Magajna

These notes have the intent to introduce the study of the nonlinear aspects of operator space theory. We investigate some results on the nonlinear theory of Banach spaces which remain valid in the noncommutative case. In particular, we show…

Operator Algebras · Mathematics 2019-12-04 Bruno de Mendonça Braga , Thomas Sinclair

We prove a hom-associative version of Hilbert's basis theorem, which includes as special cases both a non-associative version and the classical associative Hilbert's basis theorem for Ore extensions. Along the way, we develop hom-module…

Rings and Algebras · Mathematics 2025-07-16 Per Bäck , Johan Richter

In 1955 Kadison \cite{14} asked whether the analogue of the classical Burnside's theorem of the Linear Algebra holds in the infinite dimensional case. We use reproducing kernels method to solve the Kadison question. Namely, we prove that…

General Mathematics · Mathematics 2023-10-03 Mubariz T. Garayev

A bivariant functor is defined on a category of *-algebras and a category of operator ideals, both with actions of a second countable group $G$, into the category of abelian monoids. The element of the bivariant functor will be…

K-Theory and Homology · Mathematics 2011-02-01 Magnus Goffeng

We establish a dilation-theoretic characterization of the Choquet order on the space of measures on a compact convex set using ideas from the theory of operator algebras. This yields an extension of Cartier's dilation theorem to the…

Operator Algebras · Mathematics 2021-05-03 Kenneth R. Davidson , Matthew Kennedy

Wigner's Theorem states that bijections of the set P_1(H) of one-dimensional projections on a Hilbert space H that preserve transition probabilities are induced by either a unitary or an anti-unitary operator on H (which is uniquely…

Mathematical Physics · Physics 2020-08-26 Klaas Landsman , Kitty Rang

We study the *-double functor between the categories of associative and involutive algebras. It is proved that an associative algebra is isomorphic to a subalgebra of a $C\sp*$-algebra if and only if its *-double is *-isomorphic to a…

Operator Algebras · Mathematics 2009-04-08 Stanislav Popovych

Let $A$ be an amenable separable \CA and $B$ be a non-unital but $\sigma$-unital simple \CA with continuous scale. We show that two essential extensions $\tau_1$ and $\tau_2$ of $A$ by $B$ are approximately unitarily equivalent if and only…

Operator Algebras · Mathematics 2007-05-23 Huaxin Lin

Let E be an operator algebra on a Hilbert space with finite-dimensional generated C*-algebra. A classification is given of the locally finite algebras and the operator algebras obtained as limits of direct sums of matrix algebras over E…

Operator Algebras · Mathematics 2007-05-23 S. C. Power

We prove that every surjective isometry from the unit sphere of the space $K(H),$ of all compact operators on an arbitrary complex Hilbert space $H$, onto the unit sphere of an arbitrary real Banach space $Y$ can be extended to a surjective…

Functional Analysis · Mathematics 2020-05-26 Antonio M. Peralta

Alon's combinatorial Nullstellensatz, and in particular the resulting nonvanishing criterion is one of the most powerful algebraic tools in combinatorics, with many important applications. In this paper we extend the nonvanishing theorem in…

Combinatorics · Mathematics 2011-08-16 Géza Kós , Tamás Mészáros , Lajos Rónyai

The Serre-Swan theorem in differential geometry establishes an equivalence between the category of smooth vector bundles over a smooth compact manifold and the category of finitely generated projective modules over the unital ring of smooth…

Operator Algebras · Mathematics 2013-02-15 Jens Kaad

Motivated by Arveson's conjecture, we introduce a notion of hyperrigidity for a partial order on the state space of a $C^*$-algebra $B$. We show how this property is equivalent to the existence of a boundary: a subset of the pure states…

Operator Algebras · Mathematics 2023-10-27 Raphaël Clouâtre , Hridoyananda Saikia

The main purpose of this paper is to generalize the celebrated L${}^2$ extension theorem of Ohsawa-Takegoshi in several directions : the holomorphic sections to extend are taken in a possibly singular hermitian line bundle, the subvariety…

Algebraic Geometry · Mathematics 2017-05-24 Junyan Cao , Jean-Pierre Demailly , Shin-Ichi Matsumura

Around 1967, Arveson invented a striking noncommutative generalization of classical $H^\infty$, known as {\em subdiagonal algebras}, which include a wide array of examples of interest to operator theorists. Their theory extends that of the…

Operator Algebras · Mathematics 2016-09-07 David P. Blecher , Louis E. Labuschagne

We generalize to the setting of Arveson's maximal subdiagonal subalgebras of finite von Neumann algebras, the Szeg\"o $L^p$-distance estimate, and classical theorems of F. and M. Riesz, Gleason and Whitney, and Kolmogorov. In so doing, we…

Operator Algebras · Mathematics 2007-05-23 David P. Blecher , Louis E. Labuschagne

We consider an abstract sequence $\{A_n\}_{n=1}^\infty$ of closed symmetric operators on a separable Hilbert space $\mathcal{H}$. It is assumed that all $A_n$'s have equal deficiency indices $(k,k)$ and thus self-adjoint extensions…

Mathematical Physics · Physics 2023-12-15 August Bjerg

The study of open quantum systems relies on the notion of unital completely positive semigroups on $C^*$-algebras representing physical systems. The natural generalisation would be to consider the unital completely positive semigroups on…

Operator Algebras · Mathematics 2022-11-15 V. I. Yashin

We study restriction and extension properties for states on C$^*$-algebras with an eye towards hyperrigidity of operator systems. We use these ideas to provide supporting evidence for Arveson's hyperrigidity conjecture. Prompted by various…

Operator Algebras · Mathematics 2018-03-01 Raphaël Clouâtre