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The deformation of the relativistic dispersion relation caused by noncommutative (NC) Quantum Mechanics (QM) is studied using the extended phase-space formalism. The introduction of the additional commutation relations induces Lorentz…

Quantum Physics · Physics 2019-05-01 P. Leal , O. Bertolami

A calculation by Jacobson [1] strongly implies that the field equations which describe gravity are emergent phenomena. In this paper, the method is extended to the case of a non-commutative spacetime. By making use of a non-commutative…

High Energy Physics - Theory · Physics 2015-05-21 Simon Moolman

Hopf algebra methods are applied to study Drinfeld twists of (3+1)-diffeomorphisms and deformed general relativity on \emph{commutative} manifolds. A classical nonlocality length scale is produced above which microcausality emerges. Matter…

General Relativity and Quantum Cosmology · Physics 2017-03-08 P. G. N. de Vegvar

We study effects of noncommutativity on the phase space generated by a non-minimal scalar field which is conformally coupled to the background curvature in an isotropic and homogeneous FRW cosmology. These effects are considered in two…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Behrooz Malekolkalami , Mehrdad Farhoudi

As the Einstein equations are non-linear, spatial averaging and temporal evolution do not commute. Therefore, the evolution of the averaged universe is affected by inhomogeneities. It is, however, highly controversial how large these…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-15 Marina Seikel , Dominik J. Schwarz

Noncommutative version of D-dimensional relativistic particle is proposed. We consider the particle interacting with the configuration space variable $\theta^{\mu\nu}(\tau)$ instead of the numerical matrix. The corresponding Poincare…

High Energy Physics - Theory · Physics 2014-11-18 A. A. Deriglazov

We study the class of noncommutative theories in $d$ dimensions whose spatial coordinates $(x_i)_{i=1}^d$ can be obtained by performing a smooth change of variables on $(y_i)_{i=1}^d$, the coordinates of a standard noncommutative theory,…

High Energy Physics - Theory · Physics 2009-11-10 C. D. Fosco , G. Torroba

In this paper we investigate to which extent noncommutativity, a intrinsically quantum property, may influence the Friedmann-Robertson-Walker cosmological dynamics at late times/large scales. To our purpose it will be enough to explore the…

General Relativity and Quantum Cosmology · Physics 2011-08-10 Octavio Obregon , Israel Quiros

We calculate the long-range Vanderwaals force and the photoelectric cross section in a \nc set up. While we argue that non-commutativity effects could not be discerned for the Vanderwaals interactions, the result for the photoelectric…

High Energy Physics - Phenomenology · Physics 2007-08-13 K. Li , N. Chamoun

In this work, we develop and apply the WKB approximation to several examples of noncommutative quantum cosmology, obtaining the time evolution of the noncommutative universe, this is done starting from a noncommutative quantum formulation…

General Relativity and Quantum Cosmology · Physics 2009-03-24 E. Mena , O. Obregon , M. Sabido

The observational evidence for the existence of a non-zero cosmological constant is getting stronger. It is therefore timely to address the question of its eventual effect on the dynamics of galaxies, clusters and larger structures in the…

Astrophysics · Physics 2007-05-23 L. Bergstrom , U. Danielsson

The uncertainty relation, as one of the fundamental principles of quantum physics, captures the incompatibility of noncommuting observables in the preparation of quantum states. In this work, we derive two strong and universal uncertainty…

Quantum Physics · Physics 2019-04-10 Zhi-Xin Chen , Hui Wang , Jun-Li Li , Qiu-Cheng Song , Cong-Feng Qiao

The dense material in a compact star from a supernova remnant is beyond terrestrial experimentation, so phenomenological modeling is used to match astrophysical observations. This is crucial due to the complex sensitivity of compact star…

High Energy Astrophysical Phenomena · Physics 2025-07-17 Vivek Baruah Thapa , Anil Kumar , Vishal Parmar , Monika Sinha

The cosmological evolution in the radiation dominated regimen is usually computed by assuming an ideal relativistic thermal bath. In this note, we discuss the deviation from the non-interaction assumption. In either the standard model (SM)…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-21 Jose A. R. Cembranos

A quantum thermodynamic system can conserve non-commuting observables, but the consequences of this phenomenon on relaxation are still not fully understood. We investigate this problem by leveraging an observable-dependent approach to…

We study noncommutative classical Friedmann-Robertson-Walker cosmological models. The constant curvature of the spatial sections can be positive ($k=1$), negative ($k=-1$) or zero ($k=0$). The matter is represented by a perfect fluid with…

General Relativity and Quantum Cosmology · Physics 2017-01-06 G. Oliveira-Neto , A. R. Vaz

This article provides a basic introduction to some concepts of non-commutative geometry. The importance of quantum groups and quantum spaces is stressed. Canonical non-commutativity is understood as an approximation to the quantum group…

High Energy Physics - Theory · Physics 2007-05-23 Michael Wohlgenannt

There is a growing interest in investigating modified theories of gravity, primarily, with the aim of explaining the universe's accelerated expansion, which has been confirmed by several independent observations. Compact objects, like…

General Relativity and Quantum Cosmology · Physics 2021-08-16 K Nobleson , Tuhin Malik , Sarmistha Banik

Spacetime geometry is twisted (deformed) into noncommutative spacetime geometry, where functions and tensors are now star-multiplied. Consistently, spacetime diffeomorhisms are twisted into noncommutative diffeomorphisms. Their deformed Lie…

High Energy Physics - Theory · Physics 2016-09-06 Paolo Aschieri

A differential calculus, differential geometry and the E-R Gravity theory are studied on noncommutative spaces. Noncommutativity is formulated in the star product formalism. The basis for the gravity theory is the infinitesimal algebra of…

High Energy Physics - Theory · Physics 2008-12-19 Julius Wess
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