English
Related papers

Related papers: Noncommutative Rigidity

200 papers

For k at least 2, we exhibit complete k-curvature homogeneous neutral signature pseudo-Riemannian manifolds which are not locally affine homogeneous (and hence not locally homogeneous). The curvature tensor of these manifolds is modeled on…

Differential Geometry · Mathematics 2007-05-23 Peter Gilkey , Stana Nikcevic

We consider deformations of the scalar curvature of a partially integrable pseudohermitian manifold, in analogy with the work of Fischer and Marsden on Riemannian manifolds. In particular, we introduce and discuss $R$-singular spaces, give…

Differential Geometry · Mathematics 2024-04-11 Jeffrey S. Case , Pak Tung Ho

In this work, we conduct a systematic study of Hamiltonian and quasi-Hamiltonian systems within the framework of nondecomposable generalized Poisson geometry. Our focus lies on the interplay between the algebraic structure of…

Mathematical Physics · Physics 2025-10-10 C. Sardón , X. Zhao

Starting from the problem of describing cohomological invariants of Poisson manifolds we prove in a sense a ``no-go'' result: the differential graded Lie algebra of de Rham forms on a smooth Poisson manifold is formal.

Symplectic Geometry · Mathematics 2007-05-23 G. Sharygin , D. Talalaev

We give a general and nontechnical review of some aspects of noncommutative geometry as a tool to understand the structure of spacetime. We discuss the motivations for the constructions of a noncommutative geometry, and the passage from…

High Energy Physics - Theory · Physics 2008-11-04 Fedele Lizzi

We define cusp-decomposable manifolds and prove smooth rigidity within this class of manifolds. These manifolds generally do not admit a nonpositively curved metric but can be decomposed into pieces that are diffeomorphic to finite volume,…

Geometric Topology · Mathematics 2011-10-19 T. Tam Nguyen Phan

It is proposed how to impose a general type of ''noncommutativity'' within classical mechanics from first principles. Formulation is performed in completely alternative way, i.e. without any resort to fuzzy and/or star product philosophy,…

High Energy Physics - Theory · Physics 2008-12-19 Denis Kochan

We clarify the relation between noncommutative spacetimes and multifractional geometries, two quantum-gravity-related approaches where the fundamental description of spacetime is not given by a classical smooth geometry. Despite their…

High Energy Physics - Theory · Physics 2017-02-06 Gianluca Calcagni , Michele Ronco

On a Riemannian or a semi-Riemannian manifold, the metric determines invariants like the Levi-Civita connection and the Riemann curvature. If the metric becomes degenerate (as in singular semi-Riemannian geometry), these constructions no…

Differential Geometry · Mathematics 2017-01-31 Ovidiu Cristinel Stoica

The essential features of a quantum group deformation of classical symmetries of General Relativity in the case with non-vanishing cosmological constant $\Lambda$ are presented. We fully describe (anti-)de Sitter non-commutative spacetimes…

High Energy Physics - Theory · Physics 2020-03-10 Ivan Gutierrez-Sagredo , Angel Ballesteros , Giulia Gubitosi , Francisco J. Herranz

Relativistic deformed kinematics leads to a loss of the absolute locality of interactions. In previous studies, some models of noncommutative spacetimes in a two-particle system that implements locality were considered. In this work, we…

High Energy Physics - Theory · Physics 2025-04-07 J. J. Relancio

In a minimalistic view, the use of noncommutative coordinates can be seen just as a way to better express non-local interactions of a special kind: 1-particle solutions (wavefunctions) of the equation of motion in the presence of an…

High Energy Physics - Theory · Physics 2012-09-28 Gaetano Fiore

We call a finite-dimensional complex Lie algebra $\mathfrak{g}$ strongly rigid if its universal enveloping algebra $\Ug$ is rigid as an associative algebra, i.e. every formal associative deformation is equivalent to the trivial deformation.…

Rings and Algebras · Mathematics 2007-05-23 M. Bordemann , A. Makhlouf , T. Petit

In this paper we study the nonlocal effects of noncommutative spacetime on simple physical systems. Our main point is the assumption that the noncommutative effects are consequences of a background field which generates a local spin…

High Energy Physics - Theory · Physics 2009-11-11 L. P. Colatto , A. L. A. Penna , W. C. Santos

Following the general principles of noncommutative geometry, it is possible to define a metric on the space of pure states of the noncommutative algebra generated by the coordinates. This metric generalizes the usual Riemannian one. We…

High Energy Physics - Theory · Physics 2015-06-26 B. Iochum , T. Krajewski , P. Martinetti

Application of the noncommutative geometry to several physical models is considered.

General Relativity and Quantum Cosmology · Physics 2007-05-23 P. A. Saponov

We consider a curved space-time whose algebra of functions is the commutative limit of a noncommutative algebra and which has therefore an induced Poisson structure. In a simple example we determine a relation between this structure and the…

General Relativity and Quantum Cosmology · Physics 2015-06-25 J. Madore

We investigate the kinetics of a nonrelativistic particle interacting with a constant external force on a Lie-algebraic noncommutative space. The structure constants of a Lie algebra, also called noncommutative parameters, are constrained…

Mathematical Physics · Physics 2011-07-08 Yan-Gang Miao , Xu-Dong Wang , Shao-Jie Yu

We make an attempt to develop "noncommutative algebraic geometry" in which noncommutative affine schemes are in one-to-one correspondence with associative algebras. In the first part we discuss various aspects of smoothness in affine…

Algebraic Geometry · Mathematics 2016-09-07 Maxim Kontsevich , Alexander Rosenberg

This is a brief review where some basic elements of non-commutative geometry are given. The rules and ingredients that enter in the construction of the standard model and grand unification models in non-commutative geometry are summarized.…

High Energy Physics - Theory · Physics 2015-03-10 A. H. Chamseddine