English
Related papers

Related papers: Reconstruction of manifolds in noncommutative geom…

200 papers

A one parameter set of noncommutative complex algebras is given. These may be considered deformation quantisation algebras. The commutative limit of these algebras correspond to the algebra of polynomial functions over a manifold or…

Quantum Algebra · Mathematics 2009-11-10 Jonathan Gratus

In this paper which is the first of a series of papers on smooth structures, the concepts of C-structures and smooth structures are introduced and studied. The notion of smooth structure on semi-integral domains is given. It is shown that…

Commutative Algebra · Mathematics 2010-09-23 Ahmad Shafiei Deh Abad

Let $G$ be a finite group. Noncommutative geometry of unital $G$-algebras is studied. A geometric structure is determined by a spectral triple on the crossed product algebra associated with the group action. This structure is to be viewed…

Differential Geometry · Mathematics 2016-06-22 Antti J. Harju

In order to extend the spectral action principle to non-compact spaces, we propose a framework for spectral triples where the algebra may be non-unital but the resolvent of the Dirac operator remains compact. We show that an example is…

High Energy Physics - Theory · Physics 2009-07-10 Raimar Wulkenhaar

We study complete $3$-manifolds with nonnegative scalar curvature under additional regularity assumptions. We prove that a contractible such manifold is diffeomorphic to $\mathbb{R}^3$, and that an open handlebody admitting such a metric…

Differential Geometry · Mathematics 2026-04-10 Zetian Yan , Xingyu Zhu

We give a necessary and sufficient condition for orbits of commutative Hermann actions and actions of the direct product of two symmetric subgroups on compact Lie groups to be biharmonic in terms of symmetric triad with multiplicities. By…

Differential Geometry · Mathematics 2016-12-06 Shinji Ohno , Takashi Sakai , Hajime Urakawa

We introduce a wide subclass ${\cal F}(X,\omega)$ of quasi-plurisubharmonic functions in a compact K\"ahler manifold, on which the complex Monge-Amp\`ere operator is well-defined and the convergence theorem is valid. We also prove that…

Complex Variables · Mathematics 2007-05-23 Yang Xing

We consider a condition for non-degenerate commuting squares of matrix algebras (finite dimensional von Neumann algebras) called the \emph{span condition}, which in the case of the $n$-dimensional standard spin models is shown to be…

Operator Algebras · Mathematics 2007-05-23 Remus Nicoara

Alain Connes' Non-Commutative Geometry program [Connes 1994] has been recently carried out [Prodan, Leung, Bellissard 2013, Prodan, Schulz-Baldes 2014] for the entire A- and AIII-symmetry classes of topological insulators, in the regime of…

Mathematical Physics · Physics 2014-07-08 Emil Prodan

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 argue that for a certain class of symplectic manifolds the category of A-branes (which includes the Fukaya category as a full subcategory) is equivalent to a noncommutative deformation of the category of B-branes (which is equivalent to…

High Energy Physics - Theory · Physics 2007-05-23 Anton Kapustin

We reconsider differential geometry from the point of view of the quantum theory of non-relativistic spinning particles, which provides examples of supersymmetric quantum mechanics. This enables us to encode geometrical structure in…

High Energy Physics - Theory · Physics 2016-09-06 J. Froehlich , O. Grandjean , A. Recknagel

We provide an alternative proof to those by Shkarin and by Bayart and Matheron that the operator $D$ of complex differentiation supports a hypercyclic algebra on the space of entire functions. In particular we obtain hypercyclic algebras…

Functional Analysis · Mathematics 2019-03-26 Juan Bès , José Alberto Conejero , Dimitrios Papathanasiou

The mathematical apparatus of non commutative geometry and operator algebras which Connes has brought to bear to construct a rational scheme for the internal symmetries of the standard model is presented from the physicist's point of view.…

High Energy Physics - Theory · Physics 2009-10-30 Robert Brout

Quantum groups and quantum homogeneous spaces - developed by several authors since the 80's - provide a large class of examples of algebras which for many reasons we interpret as `coordinate algebras' over noncommutative spaces. This…

Operator Algebras · Mathematics 2009-12-07 Francesco D'Andrea

We present a definition of Riemannian manifold in noncommutative geometry. Using products of unbounded Kasparov modules, we show one can obtain such Riemannian manifolds from noncommutative spin^c manifolds; and conversely, in the presence…

K-Theory and Homology · Mathematics 2015-05-30 Steven Lord , Adam Rennie , Joseph C. Varilly

Let $\mathscr{A}$ be a connected cochain DG algebra such that $H(\mathscr{A})$ is a Noetherian graded algebra. We give some criteria for $\mathscr{A}$ to be homologically smooth in terms of the singularity category, the cone length of the…

Rings and Algebras · Mathematics 2024-07-23 X. -F. Mao

The formalism of non-commutative geometry of A. Connes is used to construct models in particle physics. The physical space-time is taken to be a product of a continuous four-manifold by a discrete set of points. The treatment of Connes is…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. H. Chamseddine , G. Felder , J. Fröhlich

Axioms for nonunital spectral triples, extending those introduced in the unital case by Connes, are proposed. As a guide, and for the sake of their importance in noncommutative quantum field theory, the spaces $\R^{2N}$ endowed with Moyal…

High Energy Physics - Theory · Physics 2016-08-16 V. Gayral , J. M. Gracia-Bondía , B. Iochum , T. Schücker , J. C. Varilly

Let $W$ be a compact smooth $4$-manifold that deformation retract to a PL embedded closed surface. One can arrange the embedding to have at most one non-locally-flat point, and near the point the topology of the embedding is encoded in the…

Geometric Topology · Mathematics 2021-09-16 Igor Belegradek , Beibei Liu