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Related papers: On Noncommutative and semi-Riemannian Geometry

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Motivated by the local formulae for asymptotic expansion of heat kernels in spectral geometry, we propose a definition of Ricci curvature in noncommutative settings. The Ricci operator of an oriented closed Riemannian manifold can be…

Quantum Algebra · Mathematics 2017-12-19 Remus Floricel , Asghar Ghorbanpour , Masoud Khalkhali

With the bare essentials of noncommutative geometry (defined by a spectral triple), we first describe how it naturally gives rise to gauge theories. Then, we quickly review the notion of twisting (in particular, minimally) noncommutative…

Mathematical Physics · Physics 2020-02-21 Devashish Singh

In this talk, based on work done in collaboration with G. Landi and R.J Szabo, I will review how string theory can be considered as a noncommutative geometry based on an algebra of vertex operators. The spectral triple of strings is…

High Energy Physics - Theory · Physics 2011-04-15 Fedele Lizzi

This thesis concerns the research on a Lorentzian generalization of Alain Connes' noncommutative geometry. In the first chapter, we present an introduction to noncommutative geometry within the context of unification theories. The second…

Mathematical Physics · Physics 2011-08-03 Nicolas Franco

Examples of noncommutative self-coverings are described, and spectral triples on the base space are extended to spectral triples on the inductive family of coverings, in such a way that the covering projections are locally isometric. Such…

Operator Algebras · Mathematics 2016-12-21 Valeriano Aiello , Daniele Guido , Tommaso Isola

In order to investigate to what extent the calculus of classical (pseudo-)Riemannian manifolds can be extended to a noncommutative setting, we introduce pseudo-Riemannian calculi of modules over noncommutative algebras. In this framework,…

Quantum Algebra · Mathematics 2015-11-19 Joakim Arnlind , Mitsuru Wilson

This review article intends to introduce the reader to non-integrable geometric structures on Riemannian manifolds and invariant metric connections with torsion, and to discuss recent aspects of mathematical physics--in particular…

Differential Geometry · Mathematics 2007-05-23 Ilka Agricola

We relate the recently defined spectral torsion with the algebraic torsion of noncommutative differential calculi on the example of the almost-commutative geometry of the product of a closed oriented Riemannian spin manifold $M$ with the…

Quantum Algebra · Mathematics 2025-02-04 Ludwik Dąbrowski , Yang Liu , Sugato Mukhopadhyay

We survey some aspects of the theory of noncommutative manifolds focusing on the noncommutative analogs of two-dimensional tori and low-dimensional spheres. We are particularly interested in those aspects of the theory that link the…

Quantum Algebra · Mathematics 2007-05-23 Jorge Plazas

In this paper we introduce the semi-graded rings, which extend graded rings and skew PBW extensions. For this new type of non-commutative rings we will discuss some basic problems of non-commutative algebraic geometry. In particular, we…

Rings and Algebras · Mathematics 2016-09-23 Oswaldo Lezama , Edward Latorre

In this paper, we induce a semi-Riemannian metric on the $r$-null submanifold. We establish the links between the null geometry and basics invariants of the associated semi-Riemannian geometry on $r$-null submanifold and semi-Riemannian…

General Mathematics · Mathematics 2021-12-15 Ménédore Karimumuryango , Domitien Ndayirukiye , Gilbert Nibaruta , Aboubacar Nibirantiza

We develop the formalism for noncommutative differential geometry and Riemmannian geometry to take full account of the *-algebra structure on the (possibly noncommutative) coordinate ring and the bimodule structure on the differential…

Quantum Algebra · Mathematics 2009-09-14 E. J. Beggs , S. Majid

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

We explore the relation between noncommutative geometry, in the spectral triple formulation, and quantum mechanics. To this aim, we consider a dynamical theory of a noncommutative geometry defined by a spectral triple, and study its…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Carlo Rovelli

Around 1980 Connes extended the notions of geometry to the non-commutative setting. Since then {\it non-commutative geometry} has turned into a very active area of mathematical research. As a first non-trivial example of a non-commutative…

Operator Algebras · Mathematics 2008-03-19 Franz Luef

This paper reframes Riemannian geometry as a generalized Lie algebra allowing the equations of both RG and then General Relativity to be expressed as commutation relations among fundamental operators. We begin with an Abelian Lie algebra of…

General Relativity and Quantum Cosmology · Physics 2022-09-21 Joseph E. Johnson

Recently Dabrowski etc. \cite{DL} obtained the metric and Einstein functionals by two vector fields and Laplace-type operators over vector bundles, giving an interesting example of the spinor connection and square of the Dirac operator.…

Differential Geometry · Mathematics 2024-05-21 Jian Wang , Yong Wang , Tong Wu

A Riemannian geometry of noncommutative n-dimensional surfaces is developed as a first step towards the construction of a consistent noncommutative gravitational theory. Historically, as well, Riemannian geometry was recognized to be the…

High Energy Physics - Theory · Physics 2008-11-26 M. Chaichian , A. Tureanu , R. B. Zhang , X. Zhang

We present an ab initio approach to integration theory for nonunital spectral triples. This is done without reference to local units and in the full generality of semifinite noncommutative geometry. The main result is an equality between…

Operator Algebras · Mathematics 2009-12-16 A. Carey , V. Gayral , A. Rennie , F. Sukochev

In this paper we explain how to define "lower dimensional'' volumes of any compact Riemannian manifold as the integrals of local Riemannian invariants. For instance we give sense to the area and the length of such a manifold in any…

Differential Geometry · Mathematics 2009-11-13 Raphael Ponge