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Related papers: Semiclassical analysis of the Loop Quantum Gravity…

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Quantum mechanics has been formulated in phase space, with the Wigner function as the representative of the quantum density operator, and classical mechanics has been formulated in Hilbert space, with the Groenewold operator as the…

Quantum Physics · Physics 2017-02-23 A. J. Bracken , J. G. Wood

We describe preliminary results of a detailed numerical analysis of the volume operator as formulated by Ashtekar and Lewandowski. Due to a simplified explicit expression for its matrix elements, it is possible for the first time to treat…

General Relativity and Quantum Cosmology · Physics 2009-11-11 J. Brunnemann , D. Rideout

Within the context of loop quantum gravity there are several operators which measure geometry quantities. This work examines two of these operators, volume and angle, to study quantum geometry at a single spin network vertex - ``an atom of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Seth A. Major , Michael D. Seifert

We explicitly construct and characterize all possible independent loop states in 3+1 dimensional loop quantum gravity by regulating it on a 3-d regular lattice in the Hamiltonian formalism. These loop states, characterized by the (dual)…

General Relativity and Quantum Cosmology · Physics 2008-11-26 N. D. Hari Dass , Manu Mathur

Recently, a new path integral formulation of Loop Quantum Gravity (LQG) has been derived in arXiv:1910.03763 from the reduced phase space formulation of the canonical LQG. This paper focuses on the semiclassical analysis of this path…

General Relativity and Quantum Cosmology · Physics 2020-08-05 Muxin Han , Hongguang Liu

We re-examine the semiclassical approximation to quantum gravity in the canonical formulation, focusing on the definition of a quasiclassical state for the gravitational field. It is shown that a state with classical correlations must be a…

General Relativity and Quantum Cosmology · Physics 2010-11-01 Gilad Lifschytz , Samir D. Mathur , Miguel E. Ortiz

This article presents an "in-a-nutshell" yet self-contained introductory review on loop quantum gravity (LQG) -- a background-independent, nonperturbative approach to a consistent quantum theory of gravity. Instead of rigorous and…

General Relativity and Quantum Cosmology · Physics 2014-12-30 Dah-Wei Chiou

In this PhD thesis, we introduced a new strategy to investigate the kinematical and physical predictions of self dual Loop Quantum Gravity (LQG) and by-passed the old problem of implementing quantum mechanically the so called reality…

General Relativity and Quantum Cosmology · Physics 2015-11-24 Jibril Ben Achour

The relation between Loop Quantum Gravity and Regge calculus has been pointed out many times in the literature. In particular the large spin asymptotics of the Barrett-Crane vertex amplitude is known to be related to the Regge action. In…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Eugenio Bianchi , Leonardo Modesto

This papers offers a critical discussion on the procedure by which Loop Quantum Cosmology (LQC) is constructed from the full Loop Quantum Gravity (LQG) theory. Revising recent issues in preserving SU(2) symmetry when quantizing the…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Francesco Cianfrani , Giovanni Montani

We show that for basically all states, the evolution of the expectation value of the volume operator in Wheeler-DeWitt and various homogenous isotropic loop quantum comology (LQC) models ($k=0$, coupled to massless scalar field and without…

General Relativity and Quantum Cosmology · Physics 2019-06-19 Wojciech Kaminski

A new functional calculus, developed recently for a fully non-perturbative treatment of quantum gravity, is used to begin a systematic construction of a quantum theory of geometry. Regulated operators corresponding to areas of 2-surfaces…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Abhay Ashtekar , Jerzy Lewandowski

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

A new routine is proposed to relate Loop Quant Cosmology (LQC) to Loop Quantum Gravity (LQG) from the perspective of effective dynamics. We derive the big-bang singularity resolution and big bounce from the first principle of full canonical…

General Relativity and Quantum Cosmology · Physics 2020-02-12 Muxin Han , Hongguang Liu

We apply the full theory of Loop Quantum Gravity (LQG) to cosmology and present a top-down derivation of gauge-invariant cosmological perturbation theory from quantum gravity. The derivation employs the reduced phase space formulation of…

General Relativity and Quantum Cosmology · Physics 2021-01-20 Muxin Han , Haida Li , Hongguang Liu

The properties of the Volume operator in Loop Quantum Gravity, as constructed by Ashtekar and Lewandowski, are analyzed for the first time at generic vertices of valence greater than four. The present analysis benefits from the general…

General Relativity and Quantum Cosmology · Physics 2010-11-26 Johannes Brunnemann , David Rideout

A functional calculus on the space of (generalized) connections was recently introduced without any reference to a background metric. It is used to continue the exploration of the quantum Riemannian geometry. Operators corresponding to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Abhay Ashtekar , Jerzy Lewandowski

The building blocks of a quantum theory of general relativity are expected to be discrete structures. Loop quantum gravity is formulated using a basis of spin networks (wave functions over oriented graphs with coloured edges), thus…

General Relativity and Quantum Cosmology · Physics 2015-06-17 Jacobo Diaz-Polo , Iñaki Garay

We construct normalizable, semi-classical states for the previously proposed model of quantum gravity which is formulated as a spectral triple over holonomy loops. The semi-classical limit of the spectral triple gives the Dirac Hamiltonian…

High Energy Physics - Theory · Physics 2011-03-02 Johannes Aastrup , Jesper M. Grimstrup , Mario Paschke , Ryszard Nest

The volume operator is an important kinematical quantity in the non-perturbative approach to four-dimensional quantum gravity in the connection formulation. We give a general algorithm for computing its spectrum when acting on four-valent…

General Relativity and Quantum Cosmology · Physics 2016-08-31 R. Loll