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In this paper, a Riemannian geometry of noncommutative super surfaces is developed which generalizes [4] to the super case. The notions of metric and connections on such noncommutative super surfaces are introduced and it is shown that the…

Differential Geometry · Mathematics 2022-12-29 Yong Wang , Tong Wu

We study a noncommutative analogue of a spacetime foliated by spacelike hypersurfaces, in both Riemannian and Lorentzian signatures. First, in the classical commutative case, we show that the canonical Dirac operator on the total spacetime…

Mathematical Physics · Physics 2019-09-16 Koen van den Dungen

A notion of fundamental group of spectral triples has been introduced. The notion uses a noncommutative analogue of unramified coverings. It was shown that in commutative case this fundamental group is a profinite completion of fundamental…

K-Theory and Homology · Mathematics 2007-05-23 Petr R. Ivankov , Nickolay P. Ivankov

We define pseudo-Riemannian spectral triples, an analytic context broad enough to encompass a spectral description of a wide class of pseudo-Riemannian manifolds, as well as their noncommutative generalisations. Our main theorem shows that…

Operator Algebras · Mathematics 2015-03-26 Koen van den Dungen , Mario Paschke , Adam Rennie

Two years ago, we found the supersymmetric counterpart of the spectral triple which specified noncommutative geometry. Based on the triple, we derived gauge vector supermultiplets, Higgs supermultiplets of the minimum supersymmetric…

High Energy Physics - Theory · Physics 2019-12-06 Masafumi Shimojo , Satoshi Ishihara , Hironobu Kataoka , Atsuko Matsukawa , Hikaru Sato

When aiming to apply mathematical results of non-commutative geometry to physical problems the question arises how they translate to a context in which only a part of the spectrum is known. In this article we aim to detect when a…

Mathematical Physics · Physics 2020-03-18 Lisa Glaser , Abel Stern

If two compact quantum metric spaces are close in the metric sense, then how similar are they, as noncommutative spaces? In the classical realm of Riemannian geometry, informally, if two manifolds are close in the Gromov-Hausdorff distance,…

Operator Algebras · Mathematics 2025-10-16 Carla Farsi , Frederic Latremoliere

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

This proceeding presents a synthesis of recent results on the emergence of pseudo-Riemannian structures from twisted spectral triples within the almostcommutative framework. It provides a unified algebraic mechanism for addressing the…

Mathematical Physics · Physics 2026-05-12 Gaston Nieuviarts

We explore the geometric implications of introducing a spectral cut-off on Riemannian manifolds. This is naturally phrased in the framework of non-commutative geometry, where we work with spectral triples that are \emph{truncated} by…

Mathematical Physics · Physics 2020-06-16 Lisa Glaser , Abel B. Stern

We study the problem of recovering a function on a pseudo-Riemannian manifold from its integrals over all null geodesics in three geometries: pseudo-Riemannian products of Riemannian manifolds, Minkowski spaces and tori. We give proofs of…

Differential Geometry · Mathematics 2016-08-11 Joonas Ilmavirta

We investigate the notion of subsystem in the framework of spectral triple as a generalized notion of noncommutative submanifold. In the case of manifolds, we consider several conditions on Dirac operators which turn embedded submanifolds…

Mathematical Physics · Physics 2024-04-26 Paolo Bertozzini , Wanchalerm Sucpikarnon , Apimook Watcharangkool

After recalling Snyder's idea of using vector fields over a smooth manifold as `coordinates on a noncommutative space', we discuss a two dimensional toy-model whose `dual' noncommutative coordinates form a Lie algebra: this is the well…

High Energy Physics - Theory · Physics 2009-11-11 Francesco D'Andrea

We review some applications of noncommutative geometry to the study of transverse geometry of Riemannian foliations and discuss open problems.

Differential Geometry · Mathematics 2007-05-23 Yuri Kordyukov

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 consider a generic curved non-commutative torus extending the notion of conformally deformed non-commutative torus from \cite{Connes-Tretkoff}. In general, a curved non-commutative torus is no longer represented by a spectral triple, not…

Operator Algebras · Mathematics 2019-10-03 Fedor Sukochev , Dmitriy Zanin

The geometry of spaces with indefinite inner product, known also as Krein spaces, is a basic tool for developing Operator Theory therein. In the present paper we establish a link between this geometry and the algebraic theory of…

Functional Analysis · Mathematics 2009-07-08 Franciszek Hugon Szafraniec , Michal Wojtylak

We classify and construct all real spectral triples over noncommutative Bieberbach manifolds, which are restrictions of irreducible real equivariant spectral triple over the noncommutative three-torus. We show that in the classical case the…

Quantum Algebra · Mathematics 2019-03-08 Piotr Olczykowski , Andrzej Sitarz

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

Gelfand - Na\u{i}mark theorem supplies a one to one correspondence between commutative $C^*$-algebras and locally compact Hausdorff spaces. So any noncommutative $C^*$-algebra can be regarded as a generalization of a topological space.…

Operator Algebras · Mathematics 2015-08-25 Petr Ivankov