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Related papers: Fra\"{i}ss\'e theory in operator algebras

200 papers

Fractional integral operators connected with real-valued scalar functions of matrix argument are applied in problems of mathematics, statistics and natural sciences. In this article we start considering the case of a Gauss hypergeometric…

Mathematical Physics · Physics 2014-09-09 A. M. Mathai , H. J. Haubold

We extend the well-known trace formula for Hill's equation to general one-dimensional Schr\"odinger operators. The new function $\xi$, which we introduce, is used to study absolutely continuous spectrum and inverse problems.

Spectral Theory · Mathematics 2008-02-03 Fritz Gesztesy , Helge Holden , Barry Simon , Zhong Xin Zhao

The concept of F-algebra and its representation can be extended to an arbitrary bundle. We define operations of fibered F-algebra in fiber. The paper presents the representation theory of of fibered F-algebra as well as a comparison of…

Differential Geometry · Mathematics 2011-11-09 Aleks Kleyn

The theory of abstract Friedrichs operators was introduced some fifteen years ago with the aim of providing a more comprehensive framework for the study of positive symmetric systems of first-order partial differential equations, nowadays…

Analysis of PDEs · Mathematics 2024-10-01 Marko Erceg , Sandeep Kumar Soni

We survey the developments in the model theory of tracial von Neumann algebras that have taken place in the last fifteen years. We discuss the appropriate first-order language for axiomatizing this class as well as the subclass of II$_1$…

Logic · Mathematics 2022-10-28 Isaac Goldbring , Bradd Hart

Using the recent theory of Krein--von Neumann extensions for positive functionals we present several simple criteria to decide whether a given positive functional on the full operator algebra is normal. We also characterize those…

Functional Analysis · Mathematics 2017-10-19 Zoltán Sebestyén , Zsigmond Tarcsay , Tamás Titkos

A Frattini theory for non-associative algebras was developed by Towers and results for particular classes of algebras have appeared in various articles. Especially plentiful are results on Lie algebras. It is the purpose of this paper to…

Rings and Algebras · Mathematics 2011-08-12 Chelsie Batten , Lindsey Bosko-Dunbar , Allison Hedges , J. T. Hird , Kristen Stagg , Ernest Stitzinger

In this article we show how Gr\"un's results in group theory can be used for studying the structure of class groups in normal extensions.

Number Theory · Mathematics 2011-08-30 Franz Lemmermeyer

In previous two papers, we defined fractional Brauer configuration algebras and developed their covering theory. In this paper, we study the representation theory of fractional Brauer graph algebras of type MS, a special class of fractional…

Representation Theory · Mathematics 2026-04-24 Nengqun Li , Yuming Liu

In this article, a theory of generalized oscillatory integrals (OIs) is developed whose phase functions as well as amplitudes may be generalized functions of Colombeau type. Based on this, generalized Fourier integral operators (FIOs)…

Analysis of PDEs · Mathematics 2007-05-23 Claudia Garetto , Guenther Hoermann , Michael Oberguggenberger

Conformal algebra is an axiomatic description of the operator product expansion (or rather its Fourier transform) of chiral fields in a conformal field theory. This is a review of recent developments in the subject.

q-alg · Mathematics 2008-02-03 Victor G. Kac

The well-behaved representations of the coordinate algebra of a 2-dimensional quantum complex plane are classified and a C*-algebra is defined which can be viewed as the algebra of continuous functions on the 2-dimensional quantum complex…

Quantum Algebra · Mathematics 2018-02-20 Ismael Cohen , Elmar Wagner

Starting from the definition of A-Fredholm and semi-A-Fredholm operator on the standard module over a unital C*- algebra A, introduced in [8] and [4], we construct various generalizations of these operators and obtain several results as an…

Operator Algebras · Mathematics 2020-04-17 Stefan Ivkovic

The paper deal with the noncommutative Fr\'echet ${}^*$-algebra $\mathcal{L}(s',s)$ of the so-called smooth operators, i.e. linear and continuous operators acting from the space $s'$ of slowly increasing sequences to the Fr\'echet space $s$…

Functional Analysis · Mathematics 2021-03-05 Tomasz Ciaś

Examples of Fell algebras with compact spectrum and trivial Dixmier-Douady invariant are constructed to illustrate differences with the case of continuous trace $C^*$-algebras. At the level of the spectrum, this translates to only assuming…

Operator Algebras · Mathematics 2023-04-21 Robin J. Deeley , Magnus Goffeng , Allan Yashinski

We present a self-contained development of the Weierstrass theory of those analytic functions (single-valued or multiform) which admit an algebraic addition theorem. We review the history of the theory and present detailed proofs of the…

Classical Analysis and ODEs · Mathematics 2017-12-29 Mark B. Villarino

We develop structure theory of finite Lie conformal superalgebras.

Quantum Algebra · Mathematics 2007-05-23 Davide Fattori , Victor G. Kac , Alexander Retakh

We provide a construction of Roe (C*-)algebras of general coarse spaces in terms of coarse geometric modules. This extends the classical theory of Roe algebras of metric spaces and gives a unified framework to deal with either uniform or…

Operator Algebras · Mathematics 2024-04-03 Diego Martínez , Federico Vigolo

The eikonal algebra $\mathfrak E$ of the metric graph $\Omega$ is an operator $C^*$--algebra defined by the dynamical system which describes the propagation of waves generated by sources supported in the boundary vertices of $\Omega$. This…

Operator Algebras · Mathematics 2022-12-13 M. I. Belishev , A. V. Kaplun

A local existence and uniqueness theorem for ODEs in the special algebra of generalized functions is established, as well as versions including parameters and dependence on initial values in the generalized sense. Finally, a Frobenius…

Functional Analysis · Mathematics 2017-01-10 Evelina Erlacher , Michael Grosser