English
Related papers

Related papers: Noncommutative effects in astrophysical objects: a…

200 papers

We consider astrophysical objects such as main-sequence stars, white-dwarfs and neutron stars in a noncommutative context. Noncommutativity is implemented via a deformed dispersion relation $E^{2}=p^{2}c^{2}(1+\lambda E)^{2}+m^{2}c^{4}$…

General Relativity and Quantum Cosmology · Physics 2013-05-29 Orfeu Bertolami , Carlos A. D. Zarro

We examine the cosmological implications of space-time non-commutativity, discovering yet another realization of the varying speed of light model. Our starting point is the well-known fact that non-commutativity leads to deformed dispersion…

High Energy Physics - Theory · Physics 2010-01-06 Stephon H. S. Alexander , João Magueijo

This talk is an introduction to ideas of non-commutative geometry and star products. We will discuss consequences for physics in two different settings: quantum field theories and astrophysics. In case of quantum field theory, we will…

High Energy Physics - Theory · Physics 2010-02-23 Michael Wohlgenannt

The noncommutativity concept has wide range of applications in physical and mathematical theories. Noncommutativity in the position-time coordinates concerns the microscale structure of space-time. the noncommutativity is an intrinsic…

General Relativity and Quantum Cosmology · Physics 2023-10-24 Behrooz Malekolkalami , Taimur Mohammadi

It is well known that alternative theories to the Standard Model allow -- and sometimes require -- fundamental constants, such as the fine-structure constant, $\alpha$, to vary in spacetime. We demonstrate that one way to investigate these…

High Energy Physics - Phenomenology · Physics 2025-03-17 E. -A. Kolonia , C. J. A. P. Martins , Konstantinos N. Gourgouliatos

Non-commutative geometry indicates a deformation of the energy-momentum dispersion relation $f(E)\equiv\frac{E}{pc}(\neq 1)$ for massless particles. This distorted energy-momentum relation can affect the radiation dominated phase of the…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-27 U. D. Machado , R. Opher

In this paper, we investigate the effects of non-commutative phase-space on the quintom cosmological model. In that case, we discuss $\Lambda_{1}$, $\Lambda_{2}$ and other cosmological parameters and show that they are associated to…

High Energy Physics - Theory · Physics 2018-02-22 J. Sadeghi , B. Pourhassan , Z. Nekouee , M. Shokri

We study the effects of noncommutativity of spacetime geometry on the thermodynamical properties of the de Sitter horizon. We show that noncommutativity results in modifications in temperature, entropy and vacuum energy and that these…

General Relativity and Quantum Cosmology · Physics 2009-03-24 B. Vakili , N. Khosravi , H. R. Sepangi

We study the N=1/2 supersymmetric theory on noncommutative superspace which is a deformation of usual superspace. We consider deformed Wess-Zumino model as an example and show vanishing of vacuum energy, renormalization of superpotential…

High Energy Physics - Theory · Physics 2009-11-10 Seiji Terashima , Jung-Tay Yee

We study some consequences of noncommutativity to homogeneous cosmologies by introducing a deformation of the commutation relation between the minisuperspace variables. The investigation is carried out for the Kantowski-Sachs model by means…

High Energy Physics - Theory · Physics 2009-11-10 G. D. Barbosa , N. Pinto-Neto

We consider noncommutative geometries obtained from a triangular Drinfeld twist. This allows to construct and study a wide class of noncommutative manifolds and their deformed Lie algebras of infinitesimal diffeomorphisms. This way symmetry…

Quantum Algebra · Mathematics 2010-05-13 Paolo Aschieri

We give an overview of the applications of noncommutative geometry to physics. Our focus is entirely on the conceptual ideas, rather than on the underlying technicalities. Starting historically from the Heisenberg relations, we will explain…

High Energy Physics - Theory · Physics 2023-05-30 Ali H. Chamseddine , Alain Connes , Walter D. van Suijlekom

We investigate noncommutative deformations of quantum field theories for different star products, particularly emphasizing the locality properties and the regularity of the deformed fields. Using functional analysis methods, we describe the…

High Energy Physics - Theory · Physics 2010-12-17 Michael A. Soloviev

In recent years, many new developments in theoretical physics, and in practical applications rely on different techniques of noncommutative algebras. In this review, we introduce the basic concepts and techniques of noncommutative physics…

High Energy Physics - Theory · Physics 2023-06-08 Shi-Dong Liang , Matthew J. Lake

Noncommutativity of observables is a central feature of quantum physics. It plays a fundamental role in the formulation of the uncertainty principle for complementary variables and strongly affects the laws of thermodynamics for systems…

Quantum Physics · Physics 2025-10-07 Franklin L. S. Rodrigues , Eric Lutz

We explore local consequences of a non-zero cosmological constant on astrophysical structures. We find that the effects are not only sensitive to the density of the configurations but also to the geometry. For non-homogeneous…

Astrophysics · Physics 2010-12-13 Marek Nowakowski , Andres Balaguera-Antolinez

A non-commutative multi-dimensional cosmological model is introduced and used to address the issues of compactification and stabilization of extra dimensions and the cosmological constant problem. We show that in such a scenario these…

High Energy Physics - Theory · Physics 2009-11-11 N. Khosravi , S. Jalalzadeh , H. R. Sepangi

We outline a phenomenological programme for the search of effects induced by (string-motivated) canonical noncommutative spacetime. The tests we propose are based, in analogy with a corresponding programme developed over the last few years…

High Energy Physics - Theory · Physics 2010-02-05 Giovanni Amelino-Camelia , Luisa Doplicher , Soonkeon Nam , Yun-Seok Seo

This is an introduction to an algebraic construction of a gravity theory on noncommutative spaces which is based on a deformed algebra of (infinitesimal) diffeomorphisms. We start with some fundamental ideas and concepts of noncommutative…

High Energy Physics - Theory · Physics 2007-05-23 Frank Meyer

The non-commutative electrodynamics based on the canonical Poisson gauge theory is studied in this paper. For a pure spatial non-commutativity, we investigate the plane wave solutions in the presence of a constant and uniform magnetic…

High Energy Physics - Theory · Physics 2023-11-08 O. Abla , M. J. Neves
‹ Prev 1 2 3 10 Next ›