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Related papers: Non-commutativity in modified loop cosmology

200 papers

We study oscillatory universes within the context of Loop Quantum Cosmology. We make a comparative study of flat and positively curved universes sourced by scalar fields with either positive or negative potentials. We investigate how…

General Relativity and Quantum Cosmology · Physics 2009-11-10 D. J. Mulryne , N. J. Nunes , R. Tavakol , J. E. Lidsey

We present a modified cosmological scenario that arises from the application of non-extensive thermodynamics with varying exponent. We extract the modified Friedmann equations, which contain new terms quantified by the non-extensive…

General Relativity and Quantum Cosmology · Physics 2019-03-27 Shin'ichi Nojiri , Sergei D. Odintsov , Emmanuel N. Saridakis

We propose a specialized parameterization for the Hubble parameter, inspired by $\Lambda$CDM cosmology, to investigate the cosmic expansion history of the Universe. This parameterization is employed to analyze the Universe's late-time…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-23 M. Koussour , N. Myrzakulov

We show that a contracting universe which bounces due to quantum cosmological effects and connects to the hot big-bang expansion phase, can produce an almost scale invariant spectrum of perturbations provided the perturbations are produced…

High Energy Physics - Theory · Physics 2008-11-26 Patrick Peter , E. J. C. Pinho , Nelson Pinto-Neto

In this paper, we model the bounce phase, stability, and the reconstruction of the universe by non-minimal kinetic coupling. In the process, we obtained importance information about the energy density and the matter pressure of the universe…

General Relativity and Quantum Cosmology · Physics 2026-02-10 Alireza Amani , A. S. Kubeka , E. Mahichi

We consider a noncommutative (NC) inflationary model with a homogeneous scalar field minimally coupled to gravity. The particular NC inflationary setting produces entirely new consequences. We first analyze the free field case and…

General Relativity and Quantum Cosmology · Physics 2018-05-01 S. M. M. Rasouli , N. Saba , M. Farhoudi , J. Marto , P. Moniz

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

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

We study the inflationary evolution of a scalar field $h$ with an unstable potential for the case where the Hubble parameter $H$ during inflation is larger than the instability scale $\Lambda_I$ of the potential. Quantum fluctuations in the…

High Energy Physics - Theory · Physics 2016-03-14 John Kearney , Hojin Yoo , Kathryn M. Zurek

Within the framework of loop quantum cosmology (LQC), we investigate the effect of inverse volume corrections on the low scale spontaneously broken supersymmetric (SB SUSY) and exponential inflationary potentials. The LQC modifications to…

General Relativity and Quantum Cosmology · Physics 2025-10-07 Farough Parvizi , Soma Heydari , Milad Solbi , Kayoomars Karami

The noncommutativity of the space-time had important implications for the very early Universe, when its size was of the order of the Planck length. An important implication of this effect is the deformation of the standard dispersion…

General Relativity and Quantum Cosmology · Physics 2018-10-09 Yunxin Ye , Tiberiu Harko , Shi-Dong Liang

We study the most general cosmological model with real scalar field which is minimally coupled to gravity. Our calculations are based on Friedmann-Lemaitre-Robertson-Walker (FLRW) background metric. Field equations consist of three…

General Relativity and Quantum Cosmology · Physics 2023-03-22 Medine Ildes , Metin Arik

The FRW model with non-minimally coupled massive scalar field has been investigated in LQC framework. Considered form of the potential and coupling allows applications to Higgs driven inflation. Out of two frames used in the literature to…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Michal Artymowski , Andrea Dapor , Tomasz Pawlowski

In this research work, we explore the late-time accelerated expansion of the universe within the framework of modified gravity, specifically $f(R, L_m)$ theory, by considering two non-linear models: $f(R, L_{m}) = \frac{R}{2}+(1+\eta R)…

General Relativity and Quantum Cosmology · Physics 2025-06-23 Khomesh R. Patle , G. P. Singh , Romanshu Garg

The slow-roll approximation is an analytical approach to study dynamical properties of the inflationary universe. In this article, systematic construction of the slow-roll expansion for effective loop quantum cosmology is presented. The…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Joanna Luc , Jakub Mielczarek

We present a unified framework that simultaneously addresses the dynamics of early-time cosmic inflation and late-time cosmic acceleration within the context of a single scalar field non-minimally coupled to gravity. By employing an…

General Relativity and Quantum Cosmology · Physics 2025-10-27 Seong Chan Park

It is known that in loop quantum cosmology (LQC) the universe avoids the singularity by a bounce when the matter density approaches the critical density $\rho_c$ (the order of Planck density). After incorporating the inverse volume…

General Relativity and Quantum Cosmology · Physics 2011-03-14 Hua-Hui Xiong , Jian-Yang Zhu

Inflationary cosmological perturbations of quantum-mechanical origin generically interact with all degrees of freedom present in the early Universe. Therefore, they must be viewed as an open quantum system in interaction with an…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-04 Jerome Martin , Vincent Vennin

Considering space--time to be non-commutative, we study the evolution of the universe employing the approach of Newtonian cosmology. Generalizing the conservation of energy and the first law of thermodynamics to $\kappa$-deformed…

General Relativity and Quantum Cosmology · Physics 2023-07-31 E. Harikumar , Harsha Sreekumar , Suman Kumar Panja

Anomaly-free perturbations of loop quantum cosmology with holonomy corrections reveal an $\Omega$ -deformed spacetime structure, $\Omega:=1-2\rho/\rho_c$, where $\Omega<0$ indicates a Euclidean-like space and $\Omega>0$ indicates a…

General Relativity and Quantum Cosmology · Physics 2016-12-21 Long Chen , Jian-Yang Zhu