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Related papers: Noncommutativity Effects in FRW Scalar Field Cosmo…

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We consider rotationally invariant noncommutative algebra with tensors of noncommutativity constructed with the help of additional coordinates and momenta. The algebra is equivalent to well known noncommutative algebra of canonical type. In…

Quantum Physics · Physics 2018-05-23 Kh. P. Gnatenko , O. V. Shyiko

In this paper within the scope of FRW cosmology for k = 0, \pm1 we study the dynamics of the universe for a cosmological model with a scalar field nonminimally coupled to matter. By best- fitting the model parameters with the observational…

General Relativity and Quantum Cosmology · Physics 2012-07-09 H. Farajollahi , A. Salehi

This study constrains the cosmological parameters within the scope of a spherically symmetric FLRW cosmological model, the role of a nonlinear spinor field in the universe's evolution. To test this approach, we incorporate the recent Cosmic…

General Physics · Physics 2026-05-18 Bijan Saha , Mahendra Goray

As is well known, an external magnetic field in configuration space coupled to a quantum dynamics induces noncommutativity in its velocity momentum space. By phase space duality, an external vector potential in the conjugate momentum sector…

Quantum Physics · Physics 2024-01-09 Jan Govaerts

The possibility of testing spatial noncommutativity by current experiments on normal quantum scales is investigated. For the case of both position-position and momentum-momentum noncommuting spectra of ions in crossed electric and magnetic…

Quantum Physics · Physics 2010-04-23 Jian-Zu Zhang , Ke-Lin Gao , Chuan-Gang Ning

We investigate first-order vacuum phase transitions in the presence of a non-minimally coupled scalar field starting with the coupling effect on the initial dynamics of phase transitions by defining an effective potential for the scalar…

General Relativity and Quantum Cosmology · Physics 2023-02-06 A. Savaş Arapoğlu , A. Emrah Yükselci

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

We consider a model for gravity that is invariant under global scale transformations. It includes one extra real scalar field coupled non-minimally to the gravity fields. In this model all the dimensionful parameters like the gravitational…

General Relativity and Quantum Cosmology · Physics 2012-02-06 Pankaj Jain , Purnendu Karmakar , Subhadip Mitra , Sukanta Panda , Naveen K. Singh

Quantum cosmological models are commonly described by means of semiclassical approximations in which a smooth evolution of the expectation values of elementary geometry operators replaces the classical and singular dynamics. The advantage…

General Relativity and Quantum Cosmology · Physics 2021-04-28 Przemysław Małkiewicz , Artur Miroszewski

Considering an arbitrary dimensional FLRW universe in the framework of a generalized S\'{a}ez--Ballester (SB) theory, we establish a noncommutative (NC) cosmological model. We concentrate on the predictions of NC model and compare them with…

General Relativity and Quantum Cosmology · Physics 2024-08-19 S. M. M. Rasouli , João Marto

We consider Noncommutative Quantum Mechanics with phase space noncommutativity. In particular, we show that a scaling of variables leaves the noncommutative algebra invariant, so that only the self-consistent effective parameters of the…

High Energy Physics - Theory · Physics 2009-11-11 O. Bertolami , J. G. Rosa , C. M. L. de Aragão , P. Castorina , D. Zappalà

In this work we carry out a noncommutative analysis of several Friedmann-Robert-Walker models, coupled to different types of perfect fluids and in the presence of a cosmological constant. The classical field equations are modified, by the…

High Energy Physics - Theory · Physics 2015-06-03 E. M. C. Abreu , M. V. Marcial , A. C. R. Mendes , W. Oliveira , G. Oliveira-Neto

Nojiri \& Odintsov \cite{noj1} and Hu \& Sawicki \cite{hu} have studied non-linear functions in modified gravity that explain the cosmic acceleration without cosmological constant, fulfil the conditions of local gravity \& stability and…

General Relativity and Quantum Cosmology · Physics 2019-08-14 Gauranga C Samanta , Nisha Godani

In a new model that we proposed, nonperturbative vacuum contributions to the effective action of a free quantized massive scalar field lead to a cosmological solution in which the scalar curvature becomes constant after a time $t_j$ (when…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Leonard Parker , Alpan Raval

We consider a noncommutative standard model with a minimal coupling scalar field and a dynamical deformation between the canonical momenta of its scale factor and scalar field, and a chameleon model with a non-minimally coupling scalar…

General Relativity and Quantum Cosmology · Physics 2018-05-25 Nasim Saba , Mehrdad Farhoudi

The dynamical behaviors of FRW Universe containing a posivive/negative potential scalar field in loop quantum cosmology scenario are discussed. The method of the phase-plane analysis is used to investigate the stability of the Universe. It…

General Relativity and Quantum Cosmology · Physics 2014-02-03 Xiao Liu , Kui Xiao , Jian-Yang Zhu

We study the effect of the non-commutativity on the creation of scalar particles from vacuum in the anisotropic universe space-time. We derive the deformed Klein-Gordon equation up to second order in the non-commutativity parameter using…

High Energy Physics - Theory · Physics 2016-09-06 Slimane Zaim

Many cosmological models invoke rolling scalar fields to account for the observed acceleration of the expansion of the universe. These theories generally include a potential V(phi) which is a function of the scalar field phi. Although…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Rodger I. Thompson , C. J. A. P. Martins , P. E. Vielzeuf

Within the scope of a FRW cosmological model we have studied the role of spinor field in the evolution of the Universe when it is non-minimally coupled to the gravitational one. We have considered a few types of nonlinearity. It was found…

General Relativity and Quantum Cosmology · Physics 2020-04-22 Bijan Saha

Effects of noncommutativity are investigated in planar quantum mechanics in the coordinate representation. Generally these issues are addressed by converting to the momentum space. In the first part of the work we show noncommutative…

High Energy Physics - Theory · Physics 2007-05-23 Subir Ghosh