English
Related papers

Related papers: Anti-deSitter universe dynamics in LQC

200 papers

We present quantum (and classical) Bianchi I model, with free massless scalar field, of the Universe. Our model may be treated as the simplest prototype of the quantum BKL (Belinskii-Khalatnikov-Lifshitz) scenario. The quantization is done…

General Relativity and Quantum Cosmology · Physics 2011-05-03 Piotr Dzierzak

We investigate the dynamics of the FLRW flat cosmological models in which the vacuum energy varies with redshift. A particularly well motivated model of this type is the so-called quantum field vacuum, in which both kind of terms $H^{2}$…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-15 Spyros Basilakos

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

The Dapor-Liegener model of Loop Quantum Cosmology (LQC), which depicts an emergent universe from a de Sitter regime in the contracting phase is studied from the mathematical viewpoint of dynamical systems and compared with the standard…

General Relativity and Quantum Cosmology · Physics 2018-12-05 Jaume de Haro

We construct and study Loop Quantum Cosmology (LQC) when the Barbero-Immirzi parameter takes the complex value $\gamma=\pm i$. We refer to this new quantum cosmology as complex Loop Quantum Cosmology. We proceed in making an analytic…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Jibril Ben Achour , Julien Grain , Karim Noui

We perform a LQC-quantization of the FRW cosmological model with nonminimally coupled scalar field. Making use of a canonical transformation, we recast the theory in the minimally coupled form (Einstein frame), for which standard LQC…

General Relativity and Quantum Cosmology · Physics 2013-05-21 Michal Artymowski , Andrea Dapor , Tomasz Pawlowski

We apply the idea of using a matter time gauge in quantum gravity to quantum cosmology. For the Friedmann-Lemaitre-Robertson-Walker (FLRW) Universe with dust and cosmological constant $\Lambda$, we show that the dynamics maps exactly to the…

General Relativity and Quantum Cosmology · Physics 2018-10-10 Masooma Ali , Syed Moeez Hassan , Viqar Husain

In contrast to previous work in the field, we construct the Loop Quantum Cosmology (LQC) of the flat isotropic model with a massless scalar field in the absence of higher order curvature corrections to the gravitational part of the…

General Relativity and Quantum Cosmology · Physics 2015-01-30 Madhavan Varadarajan

We study the quantum dynamics of de Sitter space formulated as a minisuperspace model with flat spatial hypersurfaces in unimodular gravity, both in the Wheeler-DeWitt approach and in loop quantum cosmology (LQC). Time evolution is defined…

General Relativity and Quantum Cosmology · Physics 2025-07-14 Steffen Gielen , Rita B. Neves

We show that simple scalar field models can give rise to curvature singularities in the effective Friedmann dynamics of Loop Quantum Cosmology (LQC). We find singular solutions for spatially flat Friedmann-Robertson-Walker cosmologies with…

General Relativity and Quantum Cosmology · Physics 2009-01-22 Thomas Cailleteau , Antonio Cardoso , Kevin Vandersloot , David Wands

We apply the nonstandard loop quantum cosmology method to quantize a flat Friedmann-Robertson-Walker cosmological model with a free scalar field and the cosmological constant $\Lambda>0$. Modification of the Hamiltonian in terms of loop…

General Relativity and Quantum Cosmology · Physics 2011-05-12 Jakub Mielczarek , Wlodzimierz Piechocki

We analyze the quantum supersymmetric cosmological FRW model with a scalar field, with a conditional probability density and the scalar field identified as time. The Hilbert space has a spinorial structure and there is only one consistent…

General Relativity and Quantum Cosmology · Physics 2016-03-23 C. Ramírez , V. Vázquez-Báez

The global dynamics of a homogeneous universe in Loop Quantum Cosmology is viewed as a scattering process of its geometrodynamical equivalent. This picture is applied to build a flexible (easy to generalize) and not restricted just to…

General Relativity and Quantum Cosmology · Physics 2010-04-22 Wojciech Kaminski , Tomasz Pawlowski

The basic idea of the LQC applies to every spatially homogeneous cosmological model, however only the spatially flat (so called $k=0$) case has been understood in detail in the literature thus far. In the closed (so called: k=1) case…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Lukasz Szulc , Wojciech Kaminski , Jerzy Lewandowski

We analyze the big bounce transition of the quantum FRW model in the setting of the nonstandard loop quantum cosmology (LQC). Elementary observables are used to quantize composite observables. The spectrum of the energy density operator is…

General Relativity and Quantum Cosmology · Physics 2011-03-28 Przemyslaw Malkiewicz , Wlodzimierz Piechocki

We give a formulation of quantum cosmology with a pressureless dust and arbitrary additional matter fields. The system has the property that its Hamiltonian constraint is linear in the dust momentum. This feature provides a natural time…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Viqar Husain , Tomasz Pawlowski

We analyze the canonical quantum dynamics of the isotropic Universe in a metric approach by adopting a self-interacting scalar field as relational time. When the potential term is absent we are able to associate the the expanding and…

General Relativity and Quantum Cosmology · Physics 2023-09-15 Eleonora Giovannetti , Fabio Maione , Giovanni Montani

We analyse the canonical quantum dynamics of the isotropic universe, as emerging from the Hamiltonian formulation of a metric f(R) gravity, viewed in the Jordan frame. The canonical method of quantization is performed by solving the…

General Relativity and Quantum Cosmology · Physics 2021-09-06 Mariaveronica De Angelis , Laria Figurato , Giovanni Montani

The quantum evolution equation of Loop Quantum Cosmology (LQC) -- the quantum Hamiltonian constraint -- is a difference equation. We relate the LQC constraint equation in vacuum Bianchi I separable (locally rotationally symmetric) models…

General Relativity and Quantum Cosmology · Physics 2013-01-25 Christine C. Dantas

In Loop Quantum Gravity mathematically rigorous models of full quantum gravity were proposed. In this paper we study a cosmological sector of one of the models describing quantum gravity with positive cosmological constant coupled to…

General Relativity and Quantum Cosmology · Physics 2022-11-09 Marcin Kisielowski