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Related papers: Mixmaster universe: semiclassical dynamics and inf…

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We study a semiclassical model of the mixmaster universe. We first derive the quantum model and then introduce its semiclassical approximation. We employ a general integral quantization method that respects the symmetries of the model given…

General Relativity and Quantum Cosmology · Physics 2023-09-06 Herve Bergeron , Jaime de Cabo Martin , Jean-Pierre Gazeau , Przemyslaw Malkiewicz

Following our previous paper, Bergeron et al, Smooth quantum dynamics of the mixmaster universe, Phys. Rev. D 92, 061302(R) (2015), concerning the quantization of the vacuum Bianchi IX model and the Born-Huang-Oppenheimer framework, we…

General Relativity and Quantum Cosmology · Physics 2016-06-29 Herve Bergeron , Ewa Czuchry , Jean-Pierre Gazeau , Przemyslaw Malkiewicz

There is a wide consensus on the correct dynamics of the background in loop quantum cosmology. In this article we make a systematic investigation of the duration of inflation by varying what we think to be the most important "unknowns" of…

General Relativity and Quantum Cosmology · Physics 2017-04-19 Killian Martineau , Aurélien Barrau , Susanne Schander

We show that anisotropic Bianchi type-IX models, with matter and cosmological constant have chaotic dynamics, connected to the presence of a saddle-center in phase space. The topology of cylinders emanating from unstable periodic orbits…

General Relativity and Quantum Cosmology · Physics 2007-05-23 H. P. de Oliveira , I. Damiao Soares , T. J. Stuchi

Semi-classical states for the Wheeler-DeWitt equation of a Bianchi type I model in the presence of a scalar field are analyzed. It is outlined how this scheme can effectively describe more general situations, where the curvature of the…

General Relativity and Quantum Cosmology · Physics 2010-12-23 Francesco Cianfrani , Giovanni Montani , Marco Muccino

We analyze the semiclassical and quantum behavior of the Bianchi IX Universe in the Polymer Quantum Mechanics framework, applied to the isotropic Misner variable, linked to the space volume of the model. The study is performed both in the…

General Relativity and Quantum Cosmology · Physics 2018-11-06 Chiara Crinò , Giovanni Montani , Giorgio Pintaudi

We analyze the quantum dynamics of the Bianchi Type IX model, as described in the so-called polymer representation of quantum mechanics, to characterize the modifications that a discrete na- ture in the anisotropy variables of the Universe…

General Relativity and Quantum Cosmology · Physics 2013-12-24 Orchidea Maria Lecian , Giovanni Montani , Riccardo Moriconi

We present a detailed discussion of the inflationary scenario in the context of inhomogeneous cosmologies. After a review of the fundamental features characterizing the inflationary model, as referred to a homogeneous and isotropic…

General Relativity and Quantum Cosmology · Physics 2010-11-11 Giovanni Imponente , Giovanni Montani

The influence of Inflation on initial (i.e. at Planck's epoch) large anisotropy of the Universe is studied, considering a more general metric than the isotropic one: the locally rotationally symmetric (L.R.S.) Bianchi IX metric. We find,…

General Relativity and Quantum Cosmology · Physics 2014-11-17 R. Bergamini , P. Sedici , P. Verrocchio

Inflationary models, especially those with plateau-type potentials, are consistent with the cosmological data, but inflation itself does not resolve the initial singularity. This singularity is resolved, for example, by the idea of the…

General Relativity and Quantum Cosmology · Physics 2024-05-16 Hiroki Matsui , Alexandros Papageorgiou , Fuminobu Takahashi , Takahiro Terada

We investigate the $\phi^2$ inflationary model in the Bianchi-I spacetime using effective spacetime description of loop quantum cosmology to understand the issues of the resolution of initial singularity, isotropization, effect of…

General Relativity and Quantum Cosmology · Physics 2013-07-11 Brajesh Gupt , Parampreet Singh

A semiclassical description of quantum systems is applied to probe the dynamics of the cosmological model of an inflationary universe with quadratic inflaton potential, described in a quantum framework of geometrodynamics. The systematic…

General Relativity and Quantum Cosmology · Physics 2022-10-27 David Brizuela , Tomasz Pawlowski

The quantum cosmology of the flat Friedmann-Lema{\^i}tre-Robertson-Walker Universe, filled with a scalar field, is considered in the de Broglie-Bohm (dBB) interpretation framework. A stiff-matter quantum bounce solution is obtained. The…

General Relativity and Quantum Cosmology · Physics 2023-07-24 G. S. Vicente , Rudnei O. Ramos , Vitória N. Magalhães

We consider the dynamics of Bianchi A scalar field models which undergo inflation. The main question is under which conditions does inflation come to an end and is succeeded by a decelerated epoch. This so-called "graceful exit" from…

General Relativity and Quantum Cosmology · Physics 2013-09-20 Florian Beyer , Leon Escobar

The Mixmaster solution to Einstein field equations was examined by C. Misner in an effort to better understand the dynamics of the early universe. We highlight the importance of the quantum version of this model for early universe. This…

General Relativity and Quantum Cosmology · Physics 2020-02-03 Hervé Bergeron , Ewa Czuchry , Jean-Pierre Gazeau , Przemysław Małkiewicz

According to the Belinski-Khalatnikov-Lifshitz conjecture, close to a spacelike singularity different spatial points decouple, and the dynamics can be described in terms of the Mixmaster (vacuum Bianchi IX) model. In order to understand the…

General Relativity and Quantum Cosmology · Physics 2022-10-07 David Brizuela , Sara F. Uria

We study the dynamics of anisotropic Bianchi type-IX models with matter and cosmological constant. The models can be thought as describing the role of anisotropy in the early stages of inflation. The concurrence of the cosmological constant…

General Relativity and Quantum Cosmology · Physics 2009-10-30 H. P. de Oliveira , I. Damiao Soares , T. J. Stuchi

The early stages of the universe evolution are discussed according to the hot big bang model and the grand unified theories. The shortcomings of big bang are summarized and their resolution by inflationary cosmology is sketched.…

High Energy Physics - Phenomenology · Physics 2008-11-26 George Lazarides

I consider a quantum system that possesses key features of quantum shape dynamics and show that the evolution of wave-packets will become increasingly classical at late times and tend to evolve more and more like an expanding classical…

General Relativity and Quantum Cosmology · Physics 2014-04-21 Tim A. Koslowski

We analyze the Bianchi IX Universe in the Polymer Quantum Mechanics framework by facing both semiclassical and purely quantum effects near the cosmological singularity. We adopt Misner variables to describe the model dynamics, applying the…

General Relativity and Quantum Cosmology · Physics 2019-12-03 Eleonora Giovannetti , Giovanni Montani
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