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Related papers: On solutions of loop quantum cosmology

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The evolution of a scalar field is explored taking into account the presence of a background fluid in a positively curved Universe in the framework of loop quantum cosmology. Though the mechanism that provides the initial conditions for…

Astrophysics · Physics 2009-11-13 N. J. Nunes

Cosmological perturbations are generally described by quantum fields on (curved but) classical space-times. While this strategy has a large domain of validity, it can not be justified in the quantum gravity era where curvature and matter…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Ivan Agullo , Abhay Ashtekar , William Nelson

A self-consistent pre-inflationary extension of the inflationary scenario with the Starobinsky potential, favored by Planck data, is studied using techniques from loop quantum cosmology (LQC). The results are compared with the quadratic…

General Relativity and Quantum Cosmology · Physics 2016-05-25 Béatrice Bonga , Brajesh Gupt

In this work we use the Loop Quantum Cosmology modified scalar-tensor reconstruction techniques in order to investigate how bouncing and inflationary cosmologies can be realized. With regard to the inflationary cosmologies, we shall be…

General Relativity and Quantum Cosmology · Physics 2018-04-18 K. Kleidis , V. K. Oikonomou

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

In the context of loop quantum cosmology, we consider an inflationary era driven by a canonical scalar field and occurring in the semiclassical regime, where spacetime is a continuum but quantum gravitational effects are important. The…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Gianluca Calcagni , Marina Cortes

In loop quantum gravity, modifications to the geometrical density cause a self-interacting scalar field to accelerate away from a minimum of its potential. In principle, this mechanism can generate the conditions that subsequently lead to…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Martin Bojowald , James E. Lidsey , David J. Mulryne , Parampreet Singh , Reza Tavakol

At the level of heuristic effective dynamics, we investigate the cosmological inflation with holonomy corrections of loop quantum cosmology (LQC) in the $k=0$ Friedmann-Robertson-Walker model with a single inflaton field subject to a simple…

General Relativity and Quantum Cosmology · Physics 2010-04-29 Dah-Wei Chiou , Kai Liu

For most initial conditions, cosmologically relevant physical modes were trans-planckian at the bounce time, often by many magnitude orders. We improve the usual loop quantum cosmology calculation of the primordial power spectra -- in the…

General Relativity and Quantum Cosmology · Physics 2018-05-23 Killian Martineau , Aurélien Barrau , Julien Grain

Loop quantum cosmology provides a nice solution of avoiding the big bang singularity through a big bounce mechanism in the high energy region. In loop quantum cosmology an inflationary universe is emergent after the big bounce, no matter…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Xin Zhang , Yi Ling

Loop quantum cosmology provides an efficient framework to study the evolution of the Universe beyond the classical Big Bang paradigm. Because of holonomy corrections, the singularity is replaced by a "bounce". The dynamics of the background…

General Relativity and Quantum Cosmology · Physics 2015-03-13 Jakub Mielczarek , Thomas Cailleteau , Julien Grain , Aurelien Barrau

Using techniques from loop quantum gravity, the standard theory of cosmological perturbations was recently generalized to encompass the Planck era. We now apply this framework to explore pre-inflationary dynamics. The framework enables us…

General Relativity and Quantum Cosmology · Physics 2015-03-12 Ivan Agullo , Abhay Ashtekar , William Nelson

Loop quantum cosmology of the closed isotropic model is studied with a special emphasis on a comparison with traditional results obtained in the Wheeler-DeWitt approach. This includes the relation of the dynamical initial conditions with…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Martin Bojowald , Kevin Vandersloot

We investigate the dynamics of super-inflation in two versions of Loop Quantum Cosmology, one in which the Friedmann equation is modified by the presence of inverse volume corrections, and one in which quadratic corrections are important.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 E. J. Copeland , D. J. Mulryne , N. J. Nunes , M. Shaeri

We investigate the observational signatures of quantum cosmology in the Cosmic Microwave Background data provided by Planck collaboration. We apply the warm inflationary paradigm with a tachyon scalar field to the loop quantum cosmology. In…

General Relativity and Quantum Cosmology · Physics 2018-04-25 Vahid Kamali , Spyros Basilakos , Ahmad Mehrabi , Meysam Motaharfar , Erfan Massaeli

This review article aims at presenting the theory of inflation. We first describe the background spacetime behavior during the slow-roll phase and analyze how inflation ends and the Universe reheats. Then, we present the theory of…

High Energy Physics - Theory · Physics 2009-11-10 Jerome Martin

Loop quantum cosmology is a symmetry-reduced application of loop quantum gravity. The theory predicts a bounce for the universe at the Planck scale and resolves the singularity of standard cosmology. The dynamics is also governed by an…

General Relativity and Quantum Cosmology · Physics 2024-06-27 Abolhassan Mohammadi

We investigate the dynamics of single and multiple scalar fields with exponential potentials, leading to power-law and assisted inflation, in loop quantum cosmology. Unlike in the classical theory, dynamical trajectories in loop quantum…

General Relativity and Quantum Cosmology · Physics 2012-07-05 Evan Ranken , Parampreet Singh

A warm inflationary universe model in loop quantum cosmology is studied. In general we discuss the condition of inflation in this framework. By using a chaotic potential, $V(\phi)\propto \phi^2$, we develop a model where the dissipation…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-21 Ramon Herrera

One common approach for cosmic inflation consists in couple Einstein's gravity with a scalar field, often referred to inflaton field. In order to derive analytic simple scenarios, we usually work in the {\it slow-roll} regime. In such an…

General Relativity and Quantum Cosmology · Physics 2021-01-01 J. R. L. Santos , P. H. R. S. Moraes
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