English
Related papers

Related papers: Lusin's C-property is not valid for functional Hil…

200 papers

We define possibly unsaturated, upper semicontinuous Fell bundles over Hausdorff, locally compact groupoids and establish a universal property for representations of their full section C*-algebras on Hilbert modules over arbitrary…

Operator Algebras · Mathematics 2026-04-07 Alcides Buss , Rohit Holkar , Ralf Meyer

This paper studies the problems of embedding and isomorphism for countably generated Hilbert C*-modules over commutative C*-algebras. When the fibre dimensions differ sufficiently, relative to the dimension of the spectrum, we show that…

Operator Algebras · Mathematics 2015-06-01 Leonel Robert , Aaron Tikuisis

We regard a right Hilbert C*-module X over a C*-algebra A endowed with an isometric *-homomorphism \phi: A\to L_A(X) as an object X_A of the C*-category of right Hilbert A-modules. Following a construction by the first author and Roberts,…

funct-an · Mathematics 2008-02-03 Sergio Doplicher , Claudia Pinzari , Rita Zuccante

Let $A$ be a $C^*$-algebra. It is shown that every absolutely summing operator from $A$ into $\ell_2$ factors through a Hilbert space operator that belongs to the 4-Schatten- von Neumann class. We also provide finite dimensinal examples…

Functional Analysis · Mathematics 2016-09-07 Narcisse Randrianantoanina

We provide the definition and fundamental properties of algebraic elements with respect to an operator satisfying hypothesis (h). Furthermore, we analyze Hilbert modules using C_0-operators relative to a bounded finitely connected region…

Operator Algebras · Mathematics 2007-05-23 Yun-Su Kim

We show that the Lusin area integral or the square function on the unit ball of $\C^n$, regarded as an operator in weighted space $L^2(w)$ has a linear bound in terms of the invariant $A_2$ characteristic of the weight. We show a…

Complex Variables · Mathematics 2010-05-05 Stefanie Petermichl , Brett D. Wick

We define a measure of noncompactness $\lambda$ on the standard Hilbert $C^*$-module $l^2(\mathcal A)$ over a unital $C^*$-algebra, such that $\lambda(E)=0$ if and only if $E$ is $\mathcal A$-precompact (i.e.\ it is $\varepsilon$-close to a…

Operator Algebras · Mathematics 2017-11-28 Dragoljub J. Kečkić , Zlatko Lazović

We study operator spaces, operator algebras, and operator modules, from the point of view of the `noncommutative Shilov boundary'. In this attempt to utilize some `noncommutative Choquet theory', we find that Hilbert C$^*-$modules and their…

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

This is a graduate-level introduction to C*-algebras, Hilbert C*-modules, vector bundles, and induced representations of groups and C*-algebras, with applications to quantization theory, phase space localization, and configuration space…

Mathematical Physics · Physics 2007-05-23 N. P. Landsman

Let X be a (right) Hilbert C*-module and let B be a C*-algebra acting on X from the left via adjointable operators. In this note we establish the equivalence of two notions of nondegeneracy for such an action of B on X. Furthermore, we…

Operator Algebras · Mathematics 2025-07-24 Elias Katsoulis , Christopher Ramsey

We continue our study of the general theory of possibly nonselfadjoint algebras of operators on a Hilbert space, and modules over such algebras, developing a little more technology to connect `nonselfadjoint operator algebra' with the…

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

We consider the problem of determining the Fourier integral in the Hilbert space of square integrable functions. Fourier integral is the scalar product of two functions belonging to the Hilbert space of square integrable functions and the…

General Mathematics · Mathematics 2012-01-19 V. N. Tibabishev

Let $\Delta$ be a closed, cocompact subgroup of $G \times \widehat{G}$, where $G$ is a second countable, locally compact abelian group. Using localization of Hilbert $C^*$-modules, we show that the Heisenberg module…

Operator Algebras · Mathematics 2022-07-12 Are Austad , Ulrik Enstad

In this paper, we investigate the relationship between the Hilbert functions and the associated properties of the graded modules. To attain this, we construct the graded modules from the sets of points in projective space, $\mathbb{P}_k^n$…

Commutative Algebra · Mathematics 2023-04-11 Damas Karmel Mgani , Makungu Mwanzalima

Let $A$ be a $C^*$-algebra. Let $E$ and $F$ be Hilbert $A$-modules with $E$ being full. Suppose that $\theta : E\to F$ is a linear map preserving orthogonality, i.e., $<\theta(x), \theta(y) > = 0$ whenever $<x, y > = 0$. We show in this…

Operator Algebras · Mathematics 2009-10-14 C. W. Leung , C. K. Ng , N. C. Wong

Woronowicz introduced the functional calculus for normal operators in Hilbert C*-modules. The aim of this paper is to translate, if possible, some basic properties of the functional calculus in Hilbert spaces to the Hilbert C*-module…

funct-an · Mathematics 2008-02-03 Johan Kustermans

We show that the unit ball of a full Hilbert $C^*$-module is sequentially compact in a certain weak topology if and only if the underlying $C^*$-algebra is finite dimensional. This provides an answer to the question posed in J.…

Operator Algebras · Mathematics 2010-05-31 Lj. Arambasic , D. Bakic , M. S. Moslehian

This paper deals mainly with some aspects of the adjointable operators on Hilbert $C^*$-modules. A new tool called the generalized polar decomposition for each adjointable operator is introduced and clarified. As an application, the general…

Functional Analysis · Mathematics 2024-04-25 Xiaofeng Zhang , Xiaoyi Tian , Qingxiang Xu

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 show that every infinite-dimensional commutative unital C*-algebra has a Hilbert C*-module admitting no frames. In particular, this shows that Kasparov's stabilization theorem for countably generated Hilbert C*-modules can not be…

Operator Algebras · Mathematics 2014-02-26 Hanfeng Li