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Related papers: Towards Cosmological Dynamics from Loop Quantum Gr…

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A key result of isotropic loop quantum cosmology is the existence of a quantum bounce which occurs when the energy density of the matter field approaches a universal maximum close to the Planck density. Though the bounce has been exhibited…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Peter Diener , Brajesh Gupt , Parampreet Singh

We conduct a (pre-)inflationary dynamics study within the framework of a simple noncommutative extension of effective loop quantum cosmology -- put forward recently by the authors -- which preserves its key features (in particular, the…

General Relativity and Quantum Cosmology · Physics 2023-08-04 Luis Rey Díaz-Barrón , Abraham Espinoza-García , S. Pérez-Payán , J. Socorro

Building upon our recently established correspondence between quantum cosmology and the hydrogen atom [1], we investigate the specific sector of a negative cosmological constant ($\Lambda < 0$) in a flat FLRW universe with dust. While the…

General Relativity and Quantum Cosmology · Physics 2026-01-29 Dipayan Mukherjee , Harkirat Singh Sahota , S. Shankaranarayanan

Inhomogeneous quantum cosmology is modeled as a dynamical system of discrete patches, whose interacting many-body equations can be mapped to a non-linear minisuperspace equation by methods analogous to Bose-Einstein condensation.…

General Relativity and Quantum Cosmology · Physics 2012-12-18 Martin Bojowald , Alexander L. Chinchilli , Christine C. Dantas , Matthew Jaffe , David Simpson

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

We study the scalar modes of linear perturbations in loop quantum cosmology. This is done on a lattice where each cell is taken to be homogeneous and isotropic and can be quantized via standard homogeneous loop quantum cosmology techniques.…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Edward Wilson-Ewing

One approach to defining dynamics for quantum gravity in a naturally timeless setting is to select a suitable matter degree of freedom as a 'clock' before quantisation. This idea of deparametrisation was recently introduced in group field…

General Relativity and Quantum Cosmology · Physics 2021-04-15 Steffen Gielen , Axel Polaczek

Loop quantum cosmology is an application of recent developments for a non-perturbative and background independent quantization of gravity to a cosmological setting. Characteristic properties of the quantization such as discreteness of…

Astrophysics · Physics 2009-11-13 Martin Bojowald

A new mathematical framework is formulated to derive the effective equations of motion for the constrained quantum system which possesses an internal clock. In the realm close to classical behavior, the quantum evolution is approximated by…

General Relativity and Quantum Cosmology · Physics 2008-12-05 Dah-Wei Chiou

We discuss how a cyclic model for the flat universe can be constructively derived from Loop Quantum Gravity. This model has a lower bounce, at small values of the scale factor, which shares many similarities with that of Loop Quantum…

General Relativity and Quantum Cosmology · Physics 2017-06-13 Francesco Cianfrani , Jerzy Kowalski-Glikman , Giacomo Rosati

The Planck collaboration has provided us rich information about the early universe, and a host of new observational missions will soon shed further light on the `anomalies' that appear to exist on the largest angular scales. From a quantum…

General Relativity and Quantum Cosmology · Physics 2015-11-18 Abhay Ashtekar , Aurelien Barrau

The quantum nature of the Big Bang is reexamined in the framework of Loop Quantum Cosmology. The strict application of a regularization procedure to the Hamiltonian, originally developed for the Hamiltonian in loop quantum gravity, leads to…

General Relativity and Quantum Cosmology · Physics 2018-08-29 Mehdi Assanioussi , Andrea Dapor , Klaus Liegener , Tomasz Pawłowski

The five-dimensional loop quantum Kaluza-Klein cosmology is constructed based on the symmetric reduction of the connection formulation of the full theory. Through semiclassical analysis, the effective scalar constraint for the cosmological…

General Relativity and Quantum Cosmology · Physics 2026-02-20 Shengzhi Li , Yongge Ma , Faqiang Yuan , Xiangdong Zhang

We investigate torsion-driven cosmological dynamics within the framework of Einstein-Cartan gravity using the De Donder-Weyl Hamiltonian formalism, where the tetrad and Lorentz connection act as independent variables and the Hamiltonian…

General Relativity and Quantum Cosmology · Physics 2026-02-18 Aarav Shah , M. Yu. Khlopov , M. Krasnov

Loop Quantum Cosmology strongly modifies the high-energy dynamics of Friedman-Robertson-Walker models and removes the big-bang singularity. We investigate how LQC corrections affect the stability properties of the Einstein static universe.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Luca Parisi , Marco Bruni , Roy Maartens , Kevin Vandersloot

We study the evolution of spatially flat Friedmann-Lema\^{i}tre-Robertson-Walker universe for chaotic and Starobinsky potentials in the framework of modified loop quantum cosmologies. These models result in a non-singular bounce as in loop…

General Relativity and Quantum Cosmology · Physics 2019-09-18 Bao-Fei Li , Parampreet Singh , Anzhong Wang

Starting with the generally well accepted opinion that quantizing an arbitrary Hamiltonian system involves picking out some additional structure on the classical phase space (the {\sl shadow} of quantum mechanics in the classical theory),…

Quantum Physics · Physics 2009-10-30 J. R. Klauder , P. Maraner

We study homogenous and isotropic quantum cosmology using the spinfoam formalism of Loop Quantum Gravity (LQG). We define a coupling of a scalar field to the 4-dimensional Lorentzian Engle-Pereira-Rovelli-Livine (EPRL) spinfoam model. We…

General Relativity and Quantum Cosmology · Physics 2024-02-14 Muxin Han , Hongguang Liu , Dongxue Qu , Francesca Vidotto , Cong Zhang

The flat, homogeneous, and isotropic universe with a massless scalar field is a paradigmatic model in Loop Quantum Cosmology. In spite of the prominent role that the model has played in the development of this branch of physics, there still…

General Relativity and Quantum Cosmology · Physics 2010-09-23 Mercedes Martin-Benito , Guillermo A. Mena Marugan , Javier Olmedo

We study gravitational collapse in effective loop quantum gravity, focusing on non-marginally bound configurations in Lema\^itre-Tolman-Bondi spacetimes. In the homogeneous limit we recover the effective dynamics of loop quantum cosmology…

General Relativity and Quantum Cosmology · Physics 2024-09-06 Lorenzo Cipriani , Francesco Fazzini , Edward Wilson-Ewing