English
Related papers

Related papers: Loop Quantum Cosmology I: Kinematics

200 papers

Considering as usual that the underlying geometry of our universe is well described by the spatially flat Friedmann-Lemaitre-Robertson-Walker line element, we review how the background of holonomy corrected Loop Quantum Cosmology (LQC)…

General Relativity and Quantum Cosmology · Physics 2019-05-01 Jaume de Haro , Llibert Aresté Saló , Supriya Pan

We study the notion of volume and its dynamics in the loop-quantum-gravity truncation known as the two-vertex model. We also show that its U(N)-symmetry reduction provides the old effective dynamics of loop quantum cosmology with an…

General Relativity and Quantum Cosmology · Physics 2024-06-17 Álvaro Cendal , Iñaki Garay , Luis J. Garay

Some typical quantization ambiguities of quantum geometry are studied within isotropic models. Since this allows explicit computations of operators and their spectra, one can investigate the effects of ambiguities in a quantitative manner.…

General Relativity and Quantum Cosmology · Physics 2011-09-30 Martin Bojowald

The canonical quantum theory of gravity -- Quantum Geometrodynamics (QG) is applied to the homogeneous Bianchi type IX cosmological model. As a result, the framework for the quantum theory of homogeneous cosmologies is developed. We show…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Arkady Kheyfets , Warner A. Miller , Ruslan Vaulin

Spatially homogeneous universes can be described in (loop) quantum gravity as condensates of elementary excitations of space. Their treatment is easiest in the second-quantised group field theory formalism which allows the adaptation of…

General Relativity and Quantum Cosmology · Physics 2014-07-24 Steffen Gielen

Quantum nature of classical flat Kasner spacetime is studied using effective spacetime description in loop quantum cosmology. We find that even though the spacetime curvature vanishes at the classical level, non-trivial quantum…

General Relativity and Quantum Cosmology · Physics 2017-04-14 Parampreet Singh

A phenomenology for the deep spatial geometry of loop quantum gravity is introduced. In the context of a simple model, an atom of space, it is shown how purely combinatorial structures can affect observations. The angle operator is used to…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Seth A. Major

In any attempt to build a quantum theory of gravity, a central issue is to unravel the structure of space-time at the smallest scale. Of particular relevance is the possible definition of coordinate functions within the theory and the study…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alejandro Corichi , Jose A. Zapata

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

Unimodular gravity is based on a modification of the usual Einstein-Hilbert action that allows one to recover general relativity with a dynamical cosmological constant. It also has the interesting property of providing, as the momentum…

General Relativity and Quantum Cosmology · Physics 2014-11-21 Dah-Wei Chiou , Marc Geiller

Within the framework of Quantum Reduced Loop Gravity we quantize the Hamiltonian for a gauge vector field. The regularization can be performed using tools analogous to the ones adopted in full Loop Quantum Gravity, while the matrix elements…

General Relativity and Quantum Cosmology · Physics 2017-06-07 Jakub Bilski , Emanuele Alesci , Francesco Cianfrani , Pietro Donà , Antonino Marciano

Loop quantum cosmology(LQC) is the symmetric model of loop quantum gravity. In this paper, we generalize the structure of loop quantum cosmology to the theories with arbitrary spacetime dimensions. The isotropic and homogenous cosmological…

General Relativity and Quantum Cosmology · Physics 2016-10-13 Xiangdong Zhang

Polymer quantum mechanics has been studied as a simplified picture that reflects some of the key properties of Loop Quantum Gravity; however, while the fate of relativistic symmetries in Loop Quantum Gravity is still not established, it is…

General Relativity and Quantum Cosmology · Physics 2017-12-06 Giovanni Amelino-Camelia , Michele Arzano , Malú Maira Da Silva , Daniel H. Orozco-Borunda

I describe a possible perspective on the current state of loop quantum gravity, at the light of the developments of the last years. I point out that a theory is now available, having a well-defined background-independent kinematics and a…

General Relativity and Quantum Cosmology · Physics 2011-05-25 Carlo Rovelli

We apply the ``consistent discretization'' approach to general relativity leaving the spatial slices continuous. The resulting theory is free of the diffeomorphism and Hamiltonian constraints, but one can impose the diffeomorphism…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Rodolfo Gambini , Jorge Pullin

Over the last three years, a number of fundamental physical issues were addressed in loop quantum gravity. These include: A statistical mechanical derivation of the horizon entropy, encompassing astrophysically interesting black holes as…

General Relativity and Quantum Cosmology · Physics 2017-08-23 Abhay Ashtekar

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

Using general features of recent quantizations of the Hamiltonian constraint in loop quantum gravity and loop quantum cosmology, a dynamical interpretation of the constraint equation as evolution equation is presented. This involves a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Martin Bojowald

Cosmology appears as the most promising way to test and constrain quantum gravity theories. Loop quantum gravity is among the most advanced attempts to perform a non-perturbative quantization of general relativity. Its cosmological…

General Relativity and Quantum Cosmology · Physics 2023-06-27 Killian Martineau

Important characteristics of the loop approach to quantum gravity are a specific choice of the algebra A of observables and of a representation of A on a measure space over the space of generalized connections. This representation is…

General Relativity and Quantum Cosmology · Physics 2011-01-27 Hanno Sahlmann