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Related papers: Noncommutative Friedmann Equations in Effective LQ…

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We study the effective cosmological dynamics, emerging as the hydrodynamics of simple condensate states, of a group field theory model for quantum gravity coupled to a massless scalar field and reduced to its isotropic sector. The quantum…

General Relativity and Quantum Cosmology · Physics 2016-11-23 Daniele Oriti , Lorenzo Sindoni , Edward Wilson-Ewing

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

We consider classical and quantum mechanics related to an additional noncommutativity, symmetric in position and momentum coordinates. We show that such mechanical system can be transformed to the corresponding one which allows employment…

High Energy Physics - Theory · Physics 2007-05-23 Branko Dragovich , Zoran Rakic

We analyze the evolution of a Friedmann-Robertson-Walker spacetime within the framework of $f(R)$ metric gravity using an exponential model. We show that $f(R)$ gravity may lead to a vanishing effective cosmological constant in the far…

General Relativity and Quantum Cosmology · Physics 2018-10-31 Luisa G. Jaime , Marcelo Salgado

We perform a LQC-quantization of the FRW cosmological model with nonminimally coupled scalar field. Making use of a canonical transformation, we recast the theory in the minimally coupled form (Einstein frame), for which standard LQC…

General Relativity and Quantum Cosmology · Physics 2013-05-21 Michal Artymowski , Andrea Dapor , Tomasz Pawlowski

This is a review paper concerned with the global consistency of the quantum dynamics of non-commutative systems. Our point of departure is the theory of constrained systems, since it provides a unified description of the classical and…

High Energy Physics - Theory · Physics 2015-05-13 F. S. Bemfica , H. O. Girotti

In this paper we take matter source with non-linear Equation of state (EoS) that has produced non-singular Emergent cosmology for spatially flat universe in General Relativity and minimally coupled scalar field with two different potentials…

General Relativity and Quantum Cosmology · Physics 2023-10-23 Rikpratik Sengupta , B. C. Paul , M. Kalam , P. Paul , A. Aich

In [arXiv:1004.2488], Baumann et al. present a new formalism for studying cosmological systems where the characteristic scale of non-linearities is much smaller than the Hubble scale. By integrating out the short-wavelength modes, it is…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-08 Hyeyoun Chung

In this Letter, we study analytically the evolutions of the flat Friedmann-Lemaitre-Robertson-Walker (FLRW) universe and its linear perturbations in the framework of {\em the dressed metric approach} in loop quantum cosmology (LQC).…

General Relativity and Quantum Cosmology · Physics 2017-09-21 Tao Zhu , Anzhong Wang , Klaus Kirsten , Gerald Cleaver , Qin Sheng

We study a classical, noncommutative (NC), Friedmann-Robertson-Walker cosmological model. The spatial sections may have positive, negative or zero constant curvatures. The matter content is a generic perfect fluid. The initial…

General Relativity and Quantum Cosmology · Physics 2016-02-12 G. A. Monerat , E. V. Corrêa Silva , C. Neves , G. Oliveira-Neto , L. G. Rezende Rodrigues , M. Silva de Oliveira

In this work quantum physics in noncommutative spacetime is developed. It is based on the work of Doplicher et al. which allows for time-space noncommutativity. The Moyal plane is treated in detail. In the context of noncommutative quantum…

High Energy Physics - Theory · Physics 2016-09-06 A. P. Balachandran , T. R. Govindarajan , C. Molina , P. Teotonio-Sobrinho

A model for a flat isotropic universe with a negative cosmological constant $\Lambda$ and a massless scalar field as sole matter content is studied within the framework of Loop Quantum Cosmology. By application of the methods introduced for…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Eloisa Bentivegna , Tomasz Pawlowski

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

We show that modelling the universe as a pre-geometric system with emergent quantum modes, and then constructing the classical limit, we obtain a new account of space and gravity that goes beyond Newtonian gravity even in the…

General Physics · Physics 2007-09-20 Reginald T Cahill

One presents a phase-space noncommutative extension of Quantum Cosmology in the context of a Kantowski-Sachs (KS) minisuperspace model. We obtain the Wheeler-DeWitt (WDW) equation for the noncommutative system through the ADM formalism and…

High Energy Physics - Theory · Physics 2009-07-24 C. Bastos , O. Bertolami , N. Dias , J. Prata

With a well-motivated extension of higher order holonomy corrections, the quantum theory of loop quantum cosmology (LQC) for the $k=0$ Friedmann-Robertson-Walker model (with a free massless scalar) is rigorously formulated. The analytical…

General Relativity and Quantum Cosmology · Physics 2009-08-18 Dah-Wei Chiou , Li-Fang Li

Loop quantum cosmology of the k=0 FRW model (with a massless scalar field) is shown to be exactly soluble if the scalar field is used as the internal time already in the classical Hamiltonian theory. Analytical methods are then used i) to…

General Relativity and Quantum Cosmology · Physics 2010-04-23 Abhay Ashtekar , Alejandro Corichi , Parampreet Singh

In this paper we will analyze the the status of gauge freedom in quantum mechanics (QM) and quantum field theory (QFT). Along with this analysis comparison with ordinary QFT will be given. We will show how the gauge freedom problem is…

Quantum Physics · Physics 2007-05-23 Jaroslaw Wawrzycki

While loop quantum cosmology (LQC) predicts a robust quantum bounce of the background evolution of a Friedmann-Robertson-Walker (FRW) spacetime prior to the standard slow-roll inflation, whereby the big bang singularity is resolved, there…

General Relativity and Quantum Cosmology · Physics 2018-12-05 Qiang Wu , Tao Zhu , Anzhong Wang

We study a noninteracting supersymmetric model in an expanding FRW spacetime. A soft supersymmetry breaking induces a nonzero contribution to the vacuum energy density. A short distance cutoff of the order of Planck length provides a scale…

High Energy Physics - Theory · Physics 2011-05-13 Neven Bilic