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Related papers: Spectral Triples for nonarchimedean local fields

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This paper establishes a link between Noncommutative Geometry and canonical quantum gravity. A semi-finite spectral triple over a space of connections is presented. The triple involves an algebra of holonomy loops and a Dirac type operator…

High Energy Physics - Theory · Physics 2009-11-13 Johannes Aastrup , Jesper M. Grimstrup , Ryszard Nest

The structure of heterotic string target space compactifications is studied using the formalism of the noncommutative geometry associated with lattice vertex operator algebras. The spectral triples of the noncommutative spacetimes are…

High Energy Physics - Theory · Physics 2009-10-31 David D. Song , Richard J. Szabo

We prove a spectral theorem for bimodules in the context of graph C*-algebras. A bimodule over a suitable abelian algebra is determined by its spectrum (i.e., its groupoid partial order) iff it is generated by the Cuntz-Krieger partial…

Operator Algebras · Mathematics 2007-05-23 Alan Hopenwasser , Jurtin R. Peters , Stephen C. Power

This is a survey of four recent papers which deal with the relationship of simple C*-algebras to the problem of computing the spectra of self-adjoint operators in the general case, especially when the spectrum is not discrete. It is an…

funct-an · Mathematics 2008-02-03 William Arveson

We construct spectral triples on a class of particular inductive limits of matrix-valued function algebras. In the special case of the Jiang-Su algebra we employ a particular $AF$-embedding.

Operator Algebras · Mathematics 2018-06-13 Jacopo Bassi , Ludwik Dabrowski

We study spectra of noncommutative dynamical systems, representations of fractal groups, and regular graphs. We explicitly compute these spectra for five examples of groups acting on rooted trees, and in three cases obtain totally…

Group Theory · Mathematics 2009-11-28 Laurent Bartholdi , Rostislav I. Grigorchuk

We consider a class of C*-algebras C(X) associated with quantum spaces such as spheres, projective spaces, and lens spaces. We introduce a non-self-adjoint operator algebra A together with an explicit functor from the category of…

Operator Algebras · Mathematics 2026-05-18 Arnaud Brothier

First, we define some concepts similar to the local compactoidity or the c-compactness, and study relationships between these concepts and the original ones. As a result, we find a characterization of the local compactoidity when its…

Functional Analysis · Mathematics 2025-02-03 Kosuke Ishizuka

Let $G=K\ltimes A$ be the semi-direct product group of a compact group $K$ acting on an abelian locally compact group $A$. We describe the $C^*$-algebra $C^*(G)$ of $G$ in terms of an algebra of operator fields defined over the spectrum of…

Operator Algebras · Mathematics 2019-04-23 Hedi Regeiba , Jean Ludwig

We give a geometrical construction of Connes spectral triples or noncommutative Dirac operators $D$ starting with a bimodule connection on the proposed spinor bundle. The theory is applied to the example of $M_2(\Bbb C)$, and also applies…

Quantum Algebra · Mathematics 2015-09-04 Edwin Beggs , Shahn Majid

We prove two results about nonunital index theory left open by [CGRS2]. The first is that the spectral triple arising from an action of the reals on a C*-algebra with invariant trace satisfies the hypotheses of the nonunital local index…

K-Theory and Homology · Mathematics 2014-02-28 A. Carey , V. Gayral , J. Phillips , A. Rennie , F. Sukochev

We show that the reduced groupoid C*-algebras of continuous fields of \'etale groupoids satisfying the rapid decay property yield continuous fields of C*-algebras. This establishes a new sufficient criterion that applies in the non-amenable…

Operator Algebras · Mathematics 2025-09-30 Tom Stoiber

In this article, we extend a well known result about real rank zero C* Algebras to higher real rank C* Algebras. The main technique used here is similar to the method in which we approximate continuous functions using projections. What we…

Operator Algebras · Mathematics 2026-04-24 Aranya Sarkar

We extend naturally the spectral triple which define noncommutative geometry (NCG) in order to incorporate supersymmetry and obtain supersymmetric Dirac operator D_M which acts on Minkowskian manifold. Inversely, we can consider the…

High Energy Physics - Theory · Physics 2014-05-07 Satoshi Ishihara , Hironobu Kataoka , Atsuko Matsukawa , Hikaru Sato , Masafumi Shimojo

In this paper we study the C*-algebras associated to continuous fields over locally compact metrisable zero dimensional spaces whose fibers are Kirchberg C*-algebras satisfying the UCT. We show that these algebras are inductive limits of…

Operator Algebras · Mathematics 2007-05-23 Marius Dadarlat , Cornel Pasnicu

We discuss some properties of the spectral triple $(A_F,H_F,D_F,J_F,\gamma_F)$ describing the internal space in the noncommutative geometry approach to the Standard Model, with $A_F=\mathbb{C}\oplus\mathbb{H}\oplus M_3(\mathbb{C})$. We show…

Mathematical Physics · Physics 2016-11-16 Francesco D'Andrea , Ludwik Dabrowski

A review of the applications of noncommutative geometry to a systematic formulation of duality symmetries in string theory is presented. The spectral triples associated with a lattice vertex operator algebra and the corresponding…

High Energy Physics - Theory · Physics 2007-05-23 Fedele Lizzi , Richard J. Szabo

The local logarithmic conformal field theory corresponding to the triplet algebra at c=-2 is constructed. The constraints of locality and crossing symmetry are explored in detail, and a consistent set of amplitudes is found. The spectrum of…

High Energy Physics - Theory · Physics 2011-09-29 Matthias R. Gaberdiel , Horst G. Kausch

It is known that the spin structure on a Riemannian manifold can be extended to noncommutative geometry using the notion of a spectral triple. For finite geometries, the corresponding finite spectral triples are completely described in…

High Energy Physics - Theory · Physics 2009-10-30 Thomas Krajewski

For a smooth manifold with boundary we construct a semigroupoid and a continuous field of C*-algebras which extend Connes' construction of the tangent groupoid. We show the asymptotic multiplicativity of \hbar-scaled truncated…

Functional Analysis · Mathematics 2007-05-23 Johannes Aastrup , Ryszard Nest , Elmar Schrohe