The noncommutative Choquet boundary

W Arveson - Journal of the American Mathematical Society, 2008 - ams.org
Let $ S $ be an operator system–a self-adjoint linear subspace of a unital $ C^* $-algebra $
A $ such that $\mathbf 1\in S $ and $ A= C^*(S) $ is generated by $ S $. A boundary …

Spectral truncations in noncommutative geometry and operator systems

A Connes, WD van Suijlekom - Communications in Mathematical Physics, 2021 - Springer
In this paper we extend the traditional framework of noncommutative geometry in order to
deal with spectral truncations of geometric spaces (ie imposing an ultraviolet cutoff in …

The Choquet boundary of an operator system

KR Davidson, M Kennedy - 2015 - projecteuclid.org
We show that every operator system (and hence every unital operator algebra) has
sufficiently many boundary representations to generate the C*-envelope. We solve a 45 …

The matricial relaxation of a linear matrix inequality

JW Helton, I Klep, S McCullough - Mathematical Programming, 2013 - Springer
Given linear matrix inequalities (LMIs) L 1 and L 2 it is natural to ask:(Q 1) when does one
dominate the other, that is, does L_1 (X) ⪰ 0 imply L_2 (X) ⪰ 0?(Q 2) when are they mutually …

Noncommutative choquet theory

KR Davidson, M Kennedy - arXiv preprint arXiv:1905.08436, 2019 - arxiv.org
We introduce a new and extensive theory of noncommutative convexity along with a
corresponding theory of noncommutative functions. We establish noncommutative …

[HTML][HTML] Multiplier algebras of complete Nevanlinna–Pick spaces: dilations, boundary representations and hyperrigidity

R Clouâtre, M Hartz - Journal of Functional Analysis, 2018 - Elsevier
We study reproducing kernel Hilbert spaces on the unit ball with the complete Nevanlinna–
Pick property through the representation theory of their algebras of multipliers. We give a …

The noncommutative Choquet boundary II: hyperrigidity

W Arveson - Israel Journal of Mathematics, 2011 - Springer
A (finite or countably infinite) set G of generators of an abstract C*-algebra A is called
hyperrigid if for every faithful representation of A on a Hilbert space A⊆ B (H) and every …

C*-envelopes for operator algebras with a coaction and co-universal C*-algebras for product systems

A Dor-On, ETA Kakariadis, E Katsoulis, M Laca… - Advances in …, 2022 - Elsevier
A cosystem consists of a possibly nonselfadoint operator algebra equipped with a coaction
by a discrete group. We introduce the concept of C*-envelope for a cosystem; roughly …

[图书][B] Semicrossed products of operator algebras by semigroups

K Davidson, A Fuller, E Kakariadis - 2017 - ams.org
We examine the semicrossed products of a semigroup action by∗-endomorphisms on a C*-
algebra, or more generally of an action on an arbitrary operator algebra by completely …

Dilation theory: a guided tour

OM Shalit - Operator theory, functional analysis and applications, 2021 - Springer
Dilation theory is a paradigm for studying operators by way of exhibiting an operator as a
compression of another operator which is in some sense well behaved. For example, every …