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Related papers: Noncommutativity Effects in FRW Scalar Field Cosmo…

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We study the effect of noncommutative spacetime geometry on one-loop corrections to the primordial curvature two-point function, arising from various forms of massless spectator matter fields interacting gravitationally with the inflaton.…

High Energy Physics - Theory · Physics 2018-09-19 H. S. Tan

We investigate the phase-space of a flat FRW universe including both a scalar field, $\phi,$ coupled to matter, and radiation. The model is inspired in scalar-tensor theories of gravity, and thus, related with $F(R)$ theories through…

General Relativity and Quantum Cosmology · Physics 2010-09-06 Genly Leon , Pavel Silveira , Carlos R. Fadragas

We investigate the possible effects on the evolution of perturbations in the inflationary epoch due to short distance physics. We introduce a suitable non local action for the inflaton field, suggested by Noncommutative Geometry, and…

High Energy Physics - Theory · Physics 2009-11-07 Fedele Lizzi , Gianpiero Mangano , Gennaro Miele , Marco Peloso

We construct algebra with noncommutativity of coordinates and noncommutativity of momenta which is rotationally invariant and equivalent to noncommutative algebra of canonical type. Influence of noncommutativity on the energy levels of…

Quantum Physics · Physics 2017-09-15 Kh. P. Gnatenko , V. M. Tkachuk

We propose a variation of spacetime noncommutative field theory to realize the stringy spacetime uncertainty relation without breaking any of the global symmetries of the homogeneous isotropic universe. We study the spectrum of metric…

High Energy Physics - Theory · Physics 2009-11-07 Robert Brandenberger , Pei-Ming Ho

We consider a flat cosmological model with a free massless scalar field and the cosmological constant $\Lambda$ in the framework of loop quantum cosmology. The scalar field plays the role of an intrinsic time. We apply the reduced phase…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Jakub Mielczarek , Wlodzimierz Piechocki

In this paper we endeavour to find a connection between the non-commutative nature of space time and the {\it zero point field}. We observe that extra effects come into play when we take into account the Compton scale effects in such a…

General Physics · Physics 2016-01-11 Burra G. Sidharth , Abhishek Das , Arka Roy

We study the cosmological aspects of a noncommutative, multidimensional universe where the matter source is assumed to be a scalar field which does not commute with the internal scale factor. We show that such noncommutativity results in…

General Relativity and Quantum Cosmology · Physics 2010-11-11 N. Khosravi , S. Jalalzadeh , H. R. Sepangi

A model for a noncommutative scalar field coupled to gravity is proposed via an extension of the Moyal product. It is shown that there are solutions compatible with homogeneity and isotropy to first non-trivial order in the perturbation of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 O. Bertolami , L. Guisado

A detailed comparative qualitative analysis and numerical simulation of evolution of the cosmological models based on the doublet of classical and phantom scalar fields with self-action. The 2-dimensional and 3-dimensional projections of…

General Relativity and Quantum Cosmology · Physics 2018-10-24 Yurii Ignat'ev , Alexander Agathonov , Irina Kokh

In this work we perform a dynamical analysis of a broad class of non-minimally coupled real scalar fields in the Friedmann-Robertson-Walker (FRW) spacetime framework. The first part of our study concerns the dynamics of an unspecified…

General Relativity and Quantum Cosmology · Physics 2019-06-18 Morteza Kerachian , Giovanni Acquaviva , Georgios Lukes-Gerakopoulos

In this paper we present noncommutative version of scalar field cosmology. We find the noncommutative Friedmann equations as well as the noncommutative Klein-Gordon equation. Interestingly the noncommutative contributions are only present…

General Relativity and Quantum Cosmology · Physics 2011-03-02 W. Guzmán , M. Sabido , J. Socorro

We analyze the quantum supersymmetric cosmological FRW model with a scalar field, with a conditional probability density and the scalar field identified as time. The Hilbert space has a spinorial structure and there is only one consistent…

General Relativity and Quantum Cosmology · Physics 2016-03-23 C. Ramírez , V. Vázquez-Báez

We explore dynamics of cosmological models with a nonminimally coupled scalar field evolving on a spatially flat Friedmann-Lemaitre-Robertson-Walker background. We consider cosmological models including the Hilbert-Einstein curvature term…

General Relativity and Quantum Cosmology · Physics 2014-10-01 Maria A. Skugoreva , Alexey V. Toporensky , Sergey Yu. Vernov

Quantum field theories on noncommutative Minkowski space are studied in a model-independent setting by treating the noncommutativity as a deformation of quantum field theories on commutative space. Starting from an arbitrary Wightman…

Mathematical Physics · Physics 2011-04-14 Harald Grosse , Gandalf Lechner

We have studied particle motion in generalized forms of noncommutative phase space, that simulate monopole and other forms of Berry curvature, that can be identified as effective internal magnetic fields, in coordinate and momentum space.…

High Energy Physics - Theory · Physics 2008-11-26 B. Basu , Subir Ghosh , S. Dhar

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

Noncommutative algebra which is rotationally invariant, time reversal invariant and equivalent to noncommutative algebra of canonical type is considered. Perihelion shift of orbit of a particle in Coulomb potential in the…

Quantum Physics · Physics 2021-04-27 Kh. P. Gnatenko

Quantum field theories on noncommutative spacetime have many different properties from those on commutative spacetime. In this paper, we study the microcausality of free scalar field on noncommutative spacetime. We expand the scalar field…

High Energy Physics - Theory · Physics 2007-07-30 Zheng Ze Ma

One of the fundamental assumptions of the standard $\Lambda$CDM cosmology is that, on large scales, all the matter-energy components of the Universe share a common rest frame. This seems natural for the visible sector, that has been in…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-26 J. A. R. Cembranos , A. L. Maroto , H. Villarrubia-Rojo