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Related papers: Isotropic Loop Quantum Cosmology

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Loop quantum cosmology applies techniques derived for a background independent quantization of general relativity to cosmological situations and draws conclusions for the very early universe. Direct implications for the singularity problem…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Martin Bojowald

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

The loop quantization of the conformal Brans-Dicke cosmology is explored in the spatially flat and Bianchi-I setting. The scalar and conformal constraints governing the canonical model are quantized using the loop techniques. The physical…

General Relativity and Quantum Cosmology · Physics 2023-12-29 Chun-Yen Lin , Xiangjing Liu , Yongge Ma , Cong Zhang

We complete the canonical quantization of the vacuum Bianchi I model within the improved dynamics scheme of loop quantum cosmology, characterizing the Hilbert structure of the physical states and providing a complete set of observables…

General Relativity and Quantum Cosmology · Physics 2015-05-30 M Martín-Benito , L J Garay , G A Mena Marugán , E. Wilson-Ewing

We investigate the quantum dynamics of the isotropic Universe in the presence of a free massless scalar field, playing the role of a physical clock. The Hilbert space is constructed via a direct analogy between the Wheeler-DeWitt equation…

General Relativity and Quantum Cosmology · Physics 2024-06-11 Gabriele Barca , Luisa Boglioni , Giovanni Montani

The linearly polarized Gowdy $T^3$ model with a massless scalar field with the same symmetries as the metric is quantized by applying a hybrid approach. The homogeneous geometry degrees of freedom are loop quantized, fact which leads to the…

General Relativity and Quantum Cosmology · Physics 2013-01-30 Daniel Martín-de Blas , Mercedes Martín-Benito , Guillermo A. Mena Marugán

Loop quantum gravity and cosmology are reviewed with an emphasis on evaluating the dynamics, rather than constructing it. The three crucial parts of such an analysis are (i) deriving effective equations, (ii) controlling the theory's…

General Relativity and Quantum Cosmology · Physics 2011-01-31 Martin Bojowald

Recollapsing homogeneous and isotropic models present one of the key ingredients for cyclic scenarios. This is considered here within a quantum cosmological framework in presence of a free scalar field with, in turn, a negative cosmological…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald , Reza Tavakol

We find a Friedmann model with appropriate matter/energy density such that the solution of the Wheeler-DeWitt equation exactly corresponds to the classical evolution. The well-known problems in quantum cosmology disappear in the resulting…

General Relativity and Quantum Cosmology · Physics 2015-09-21 Moncy V. John

In this work we analyze the evolution of the quantum Mixmaster cosmological model within an effective approach. In particular, we study the behaviour of the scale factor and anisotropies of the theory, and determine how it deviates from its…

General Relativity and Quantum Cosmology · Physics 2024-01-09 Héctor Hugo Hernández Hernández , Gustavo Alejandro Sánchez Herrera

Loop quantum cosmology (LQC) is very powerful to deal with the behavior of early universe. And the effective loop quantum cosmology gives a successful description of the universe in the semiclassical region. We consider the apparent horizon…

General Relativity and Quantum Cosmology · Physics 2010-04-15 Li-Fang Li , Jian-Yang Zhu

In approaches to quantum gravity, where smooth spacetime is an emergent approximation of a discrete Planckian fundamental structure, any standard effective field theoretical description will miss part of the degrees of freedom and thus…

General Relativity and Quantum Cosmology · Physics 2019-11-04 Lautaro Amadei , Alejandro Perez

Closed, singularity-free, inflationary cosmological models have recently been studied in the context of general relativity. Despite their appeal, these so called emergent models suffer from a number of limitations. These include the fact…

Astrophysics · Physics 2009-11-10 David J. Mulryne , Reza Tavakol , James E. Lidsey , George F. R. Ellis

Loop quantum cosmology is a symmetry reduced quantization of cosmological spacetimes based on loop quantum gravity. While it has been successful in resolution of various cosmological singularities and connecting Planck scale physics to…

General Relativity and Quantum Cosmology · Physics 2019-12-25 Klaus Liegener , Parampreet Singh

Multidimensional cosmological models with $n~(n > 1)$ Einstein spaces are discussed classically and with respect to canonical quantization. These models are integrable in the case of Ricci flat internal spaces. For negative curvature of the…

General Relativity and Quantum Cosmology · Physics 2009-09-25 U. Bleyer , A. Zhuk

In loop quantum cosmology the quantum dynamics is well understood. We approximate the full quantum dynamics in the infinite dimensional Hilbert space by projecting it on a finite dimensional submanifold thereof, spanned by suitably chosen…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Victor Taveras

The problems encountered in trying to quantize the various cosmological models, are brought forward by means of a concrete example. The Automorphism groups are revealed as the key element through which G.C.T.'s can be used for a general…

General Relativity and Quantum Cosmology · Physics 2011-07-19 T. Christodoulakis

The dynamics of the expanding universe is analyzed in terms of the quantum geometrodynamical model. It is shown that the equations of quantum theory in the form of the eigenvalues equation similar to the stationary Schr\"{o}dinger equation…

General Relativity and Quantum Cosmology · Physics 2013-11-22 V. E. Kuzmichev , V. V. Kuzmichev

Recently the mechanism was found which allows avoidance of the cosmological singularity within the semi-classical formulation of Loop Quantum Gravity. Numerical studies show that the presence of self-interaction potential of the scalar…

General Relativity and Quantum Cosmology · Physics 2007-05-23 G. V. Vereshchagin

In this paper we study dynamics of the closed FRW model with holonomy corrections coming from loop quantum cosmology. We consider models with a scalar field and cosmological constant. In case of the models with cosmological constant and…

General Relativity and Quantum Cosmology · Physics 2009-11-19 Jakub Mielczarek , Orest Hrycyna , Marek Szydlowski