English
Related papers

Related papers: On orthogonal systems in Hilbert C*-modules

200 papers

We introduce the $B$-spline interpolation problem corresponding to a $C^*$-valued sesquilinear form on a Hilbert $C^*$-module and study its basic properties as well as the uniqueness of solution. We first study the problem in the case when…

Operator Algebras · Mathematics 2025-02-26 Rasoul Eskandari , Michael Frank , Vladimir Manuilov , Mohammad Sal Moslehian

In this paper we provide descriptions of the Whitehead groups with coefficients in a ring of the Hilbert modular group and its reduced version, as well as for the topological K-theory of $C^*$-algebras, after tensoring with $\mathbb{Q}$, by…

K-Theory and Homology · Mathematics 2017-06-16 Luis Jorge Sánchez Saldaña , Mario Velásquez

The algebraic structure of moduli spaces of 3d N=2 supersymmetric gauge theories is studied by computing the Hilbert series which is a generating function that counts gauge invariant operators in the chiral ring. These U(N_c) theories with…

High Energy Physics - Theory · Physics 2015-11-24 Amihay Hanany , Chiung Hwang , Hyungchul Kim , Jaemo Park , Rak-Kyeong Seong

The radius of comparison is an invariant for unital C*-algebras which extends the theory of covering dimension to noncommutative spaces. We extend its definition to general C*-algebras, and give an algebraic (as opposed to…

Operator Algebras · Mathematics 2010-08-25 Bruce Blackadar , Leonel Robert , Aaron P. Tikuisis , Andrew S. Toms , Wilhelm Winter

We study the ideal structure of $C^*$-algebras arising from $C^*$-correspondences. We prove that gauge-invariant ideals of our $C^*$-algebras are parameterized by certain pairs of ideals of original $C^*$-algebras. We show that our…

Operator Algebras · Mathematics 2007-05-23 Takeshi Katsura

A new homological symmetry condition is exhibited that extends and unifies several recently defined and widely used concepts. Applications include general constructions of tilting modules and derived equivalences, and characterisations of…

Representation Theory · Mathematics 2015-06-11 Hongxing Chen , Steffen Koenig

The Kaczmarz algorithm in Hilbert spaces is a classical iterative method for stably recovering vectors from inner product data. In this paper, we extend the algorithm to the setting of Hilbert $C^*$-modules and establish analogues of its…

Functional Analysis · Mathematics 2025-08-20 Daniel Alpay , Chad Berner , Eric S. Weber

The duality principle for Gabor frames is one of the pillars of Gabor analysis. We establish a far-reaching generalization to Morita equivalent $C^*$-algebras where the equivalence bimodule is a finitely generated projective Hilbert…

Operator Algebras · Mathematics 2019-05-07 Are Austad , Mads S. Jakobsen , Franz Luef

We extend the spectral theory of commutative C*-categories to the non full-case, introducing a suitable notion of spectral spaceoid provinding a duality between a category of "non-trivial" *-functors of non-full commutative C*-categories…

Operator Algebras · Mathematics 2025-11-04 Paolo Bertozzini , Roberto Conti , Wicharn Lewkeeratiyutkul , Kasemsun Rutamorn

We consider modules $M$ over Lie algebroids ${\mathfrak g}_A$ which are of finite type over a local noetherian ring $A$. Using ideals $J\subset A$ such that ${\mathfrak g}_A \cdot J\subset J $ and the length $\ell_{{\mathfrak g}_A}(M/JM)<…

Commutative Algebra · Mathematics 2015-12-24 Rolf Källström , Yohannes Tadesse

In this paper we consider A-Fredholm and semi-A-Fredholm operators on Hilbert C*-modules over a W*-algebra A defined in [3],[10]. Using the assumption that A is a W*-algebra (and not an arbitrary C*-algebra), we obtain several results such…

Operator Algebras · Mathematics 2020-02-18 Stefan Ivkovic

In this note we show that an unbounded regular operator $t$ on Hilbert $C^*$-modules over an arbitrary $C^*$ algebra $ \mathcal{A}$ has polar decomposition if and only if the closures of the ranges of $t$ and $|t|$ are orthogonally…

Operator Algebras · Mathematics 2025-04-29 Michael Frank , Kamran Sharifi

We present three versions of the Lax-Milgram theorem in the framework of Hilbert C*-modules, two for those over W*-algebras and one for those over C*-algebras of compact operators. It is remarkable that while the Riesz theorem is not valid…

Operator Algebras · Mathematics 2025-04-29 R. Eskandari , M. Frank , V. M. Manuilov , M. S. Moslehian

We investigate the notion of conditionally positive definite in the context of Hilbert $C^*$-modules and present a characterization of the conditionally positive definiteness in terms of the usual positive definiteness. We give a Kolmogorov…

Operator Algebras · Mathematics 2017-09-26 Mohammad Sal Moslehian

We explain the precise relationship between two module-theoretic descriptions of sheaves on an involutive quantale, namely the description via so-called Hilbert structures on modules and that via so-called principally generated modules. For…

Category Theory · Mathematics 2009-06-11 Hans Heymans , Isar Stubbe

In the present research, we embark on a comprehensive inquiry into K-Riesz bases and K-g Riesz bases as they manifest within pro-C*-Hilbert modules. Adopting a unique approach, we interpret the structure of K-Riesz bases through the lens of…

Functional Analysis · Mathematics 2023-11-09 Roumaissae Eljazzar , Mohamed Rossafi

The theory of one-sided $M$-ideals and multipliers of operator spaces is simultaneously a generalization of classical $M$-ideals, ideals in operator algebras, and aspects of the theory of Hilbert $C^*$-modules and their maps. Here we give a…

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

In this paper, we introduce notions called inverse set and inverse correspondence over inverse semigroups. These are analogies of Hilbert $C^*$-modules and \Ccorrs in the $C^*$-algebra theory. We show that inverse semigroups and inverse…

Operator Algebras · Mathematics 2024-04-10 Tomoki Uchimura

We describe representations of groupoid C*-algebras on Hilbert modules over arbitrary C*-algebras by a universal property. For Hilbert space representations, our universal property is equivalent to Renault's Integration-Disintegration…

Operator Algebras · Mathematics 2019-04-30 Alcides Buss , Rohit Holkar , Ralf Meyer

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