English
Related papers

Related papers: Modules, completely positive maps, and a generaliz…

200 papers

We give a direct proof for the positivity of Kirillov's character on the convolution algebra of smooth, compactly supported functions on a connected, simply connected nilpotent Lie group $G$. Then we use this positivity result to construct…

Representation Theory · Mathematics 2020-03-17 Ehssan Khanmohammadi

Results concerning recurrence and ergodicity are proved in an abstract Hilbert space setting based on the proof of Khintchine's recurrence theorem for sets, and on the Hilbert space characterization of ergodicity. These results are carried…

Dynamical Systems · Mathematics 2018-07-02 Rocco Duvenhage , Anton Stroh

We prove a reduction theorem for capacity of positive maps of finite dimensional C*-algebras, thus reducing the computation of capacity to the case when the image of a nonscalar projection is never a projection.

Quantum Physics · Physics 2007-05-23 Erling Stormer

We generalize a preceding simple proof of the Jamiolkowski criterion to check whether a given linear map between algebras of operators is completely positive or not. The generalization is performed to embrace all algebras of Hilbert-Schmidt…

Mathematical Physics · Physics 2007-05-23 D. Salgado , J. L. Sanchez-Gomez

We develop a theory of Valuation Hilbert Modules and prove a version of Beurling's theorem for these. Then we apply our version of Beurling's theorem to obtain complete descriptions of the closed invariant subspaces of a number of Hilbert…

Complex Variables · Mathematics 2023-06-23 Charles W. Neville

Let $A$ be a $C^*$-algebra, $H$ be a Hilbert $A$-module and $K(H)$ be the closure of the set of finite rank module maps. We show that the $W^*$-algebra of all bounded $A^{**}$-module maps on the smallest self-dual Hilbert $A^{**}$-module…

Operator Algebras · Mathematics 2023-11-28 Huaxin Lin

Suppose $A$ is a pro-C*-algebra. Let $L_{A}(E)$ be the pro-C*-algebra of adjointable operators on a Hilbert $A$-module $E$ and let $K_{A}(E)$ be the closed two sided $*$-ideal of all compact operators on $E$. We prove that if $E$ be a full…

Operator Algebras · Mathematics 2016-12-13 Khadijeh Karimi , Kamran Sharifi

We extend the covariant GNS representation of Niculescu, Str\"oh and Zsid\'o for C*-dynamical systems with time-evolution of the system (dynamics) a homomorphism of C*-algebras, to any dynamical systems, where the dynamics is an unital…

Operator Algebras · Mathematics 2012-02-03 Carlo Pandiscia

The goal of this paper is to generalize several basic results from the theory of $\cal{D}$-modules to the representation theory of rational Cherednik algebras. We relate characterizations of holonomic modules in terms of singular support…

Representation Theory · Mathematics 2016-11-21 Daniel Thompson

We prove that the KSGNS construction can be viewed as an endofunctor on a category whose objects are positive $C^*$-correspondences from a fixed $C^*$-algebra and morphisms are given by intertwiners which account for automorphisms of the…

Operator Algebras · Mathematics 2026-05-11 Lucus Brady , Ryan Grady

In this article we consider generalisation of Michelson contrast for positive operators of countably decomposable $W^*$-algebras and find a few several of its properties.

Functional Analysis · Mathematics 2024-01-30 Sami Abdullah Abed , Irina Nikolaeva , Andrei Novikov

The aim of the present paper is to describe self-duality and C*- reflexivity of Hilbert {\bf A}-modules $\cal M$ over monotone complete C*-algebras {\bf A} by the completeness of the unit ball of $\cal M$ with respect to two types of…

funct-an · Mathematics 2025-04-29 Michael Frank

We show that, when $A$ is a separable C*-algebra, every countably generated Hilbert $A$-module is projective (with bounded module maps as morphisms). We also study the approximate extensions of bounded module maps. In the case that $A$ is a…

Operator Algebras · Mathematics 2023-01-12 Lawrence G. Brown , Huaxin Lin

In a previous paper, we presented an Abstract Beurling's Theorem for valuation Hilbert modules over valuation algebras. In this paper, we shall apply this theorem to obtain complete descriptions of the closed invariant subspaces of a number…

Complex Variables · Mathematics 2021-09-03 Charles W. Neville

Let K be a comonad on a model category M. We provide conditions under which the associated category of K-coalgebras admits a model category structure such that the forgetful functor to M creates both cofibrations and weak equivalences. We…

Algebraic Topology · Mathematics 2014-02-26 Kathryn Hess , Brooke Shipley

We give a short proof of the nuclearity property of a class of Cuntz-Pimsner algebras associated with a Hilbert A-bimodule M, where A is a separable and nuclear C*-algebra. We assume that the left A-action on the bimodule M is given in…

Operator Algebras · Mathematics 2011-11-18 Fernando Lledó , Ezio Vasselli

Every symmetric generating functional of a convolution semigroup of states on a locally compact quantum group is shown to admit a dense unital $*$-subalgebra with core-like properties in its domain. On the other hand we prove that every…

Operator Algebras · Mathematics 2021-07-15 Adam Skalski , Ami Viselter

We introduce a notion of Krein C*-module over a C*-algebra and more generally over a Krein C*-algebra. Some properties of Krein C*-modules and their categories are investigated.

Operator Algebras · Mathematics 2014-09-05 Paolo Bertozzini , Kasemsun Rutamorn

We explain a correct proof of the decomposition theorem for direct images of constant Hodge modules by proper K\"ahler morphisms of complex manifolds. We also give some examples showing certain difficulty in the non-constant Hodge module…

Algebraic Geometry · Mathematics 2022-05-27 Morihiko Saito

Supervised learning in reproducing kernel Hilbert space (RKHS) and vector-valued RKHS (vvRKHS) has been investigated for more than 30 years. In this paper, we provide a new twist to this rich literature by generalizing supervised learning…

Machine Learning · Statistics 2024-06-27 Yuka Hashimoto , Masahiro Ikeda , Hachem Kadri