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Related papers: The volume operator in covariant quantum gravity

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The volume of the quantum mechanical state space over $n$-dimensional real, complex and quaternionic Hilbert-spaces with respect to the canonical Euclidean measure is computed, and explicit formulas are presented for the expected value of…

Mathematical Physics · Physics 2009-11-11 Attila Andai

Recently, a new class of scalar constraint operators has been introduced in loop quantum gravity. They are defined on a space of solutions to the Gauss constraint and partial solutions to the vector constraint, called a vertex Hilbert…

General Relativity and Quantum Cosmology · Physics 2021-05-03 Marcin Kisielowski

A quantum hamiltonian which evolves the gravitational field according to time as measured by constant surfaces of a scalar field is defined through a regularization procedure based on the loop representation, and is shown to be finite and…

General Relativity and Quantum Cosmology · Physics 2011-09-30 Carlo Rovelli , Lee Smolin

Within a perturbative cosmological regime of loop quantum gravity corrections to effective constraints are computed. This takes into account all inhomogeneous degrees of freedom relevant for scalar metric modes around flat space and results…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Martin Bojowald , Hector Hernandez , Mikhail Kagan , Aureliano Skirzewski

This review is devoted to the analysis of the mutual consistency of the spin foam and canonical loop quantizations in three and four spacetime dimensions. In the three-dimensional context, where the two approaches are in good agreement, we…

General Relativity and Quantum Cosmology · Physics 2012-08-21 Sergei Alexandrov , Marc Geiller , Karim Noui

Certain versions of mimetic gravity have recently been claimed to present potential covariant theories of canonically modified spherically symmetric gravity, motivated by ingredients from loop quantum gravity. If such an equivalence were to…

General Relativity and Quantum Cosmology · Physics 2024-04-22 Martin Bojowald , Erick I. Duque

In this thesis we consider the problem of dynamics in canonical loop quantum gravity, primarily in the context of deparametrized models, in which a scalar field is taken as a physical time variable for the dynamics of the gravitational…

General Relativity and Quantum Cosmology · Physics 2021-01-01 Ilkka Mäkinen

I review the formalism of loop quantum gravity, in both its real and complex formulations, and spin foam theory which is its path integral counterpart. Spin networks for non-compact groups are introduced (following hep-th/0205268) to deal…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Etera R. Livine

This letter is motivated by the recent papers by Dittrich and Thiemann and, respectively, by Rovelli discussing the status of Quantum Geometry in the dynamical sector of Loop Quantum Gravity. Since the papers consider model examples, we…

General Relativity and Quantum Cosmology · Physics 2008-11-07 Wojciech Kaminski , Jerzy Lewandowski , Lukasz Szulc

We study time-reversal and parity ---on the physical manifold and in internal space--- in covariant loop gravity. We consider a minor modification of the Holst action which makes it transform coherently under such transformations. The…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Carlo Rovelli , Edward Wilson-Ewing

The volume operator plays a pivotal role for the quantum dynamics of Loop Quantum Gravity (LQG). It is essential in order to construct Triad operators that enter the Hamiltonian constraint and which become densely defined operators on the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Kristina Giesel , Thomas Thiemann

We investigate puncture statistics based on the covariant area spectrum in loop quantum gravity. First, we consider Maxwell-Boltzmann statistics with a Gibbs factor for punctures. We establish formulae which relate physical quantities such…

High Energy Physics - Theory · Physics 2016-08-24 Takashi Tamaki

As a toy model for the implementation of the diffeomorphism constraint, the interpretation of the resulting states, and the treatment of ordering ambiguities in loop quantum gravity, we consider the Hilbert space of spatially diffeomorphism…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hanno Sahlmann

In this paper explore the relation between covariant and canonical approaches to quantum gravity and $BF$ theory. We will focus on the dynamical triangulation and spin-foam models, which have in common that they can be defined in terms of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Matthias Arnsdorf

Variables adapted to the quantum dynamics of spherically symmetric models are introduced, which further simplify the spherically symmetric volume operator and allow an explicit computation of all matrix elements of the Euclidean and…

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

We propose an approach which, by combining insights from Loop Quantum Gravity (LQG), Topos theory, Non-commutative Geometry \`a la Connes, and spacetime relationalism, provides fertile ground for the search of an adequate spacetime picture…

General Relativity and Quantum Cosmology · Physics 2021-03-12 Alejandro Ascárate

We perform a quantization of the loop gravity phase space purely in terms of spinorial variables, which have recently been shown to provide a direct link between spin network states and simplicial geometries. The natural Hilbert space to…

General Relativity and Quantum Cosmology · Physics 2012-02-03 Etera R. Livine , Johannes Tambornino

In this paper, a version of polymer quantum mechanics, which is inspired by loop quantum gravity, is considered and shown to be equivalent, in a precise sense, to the standard, experimentally tested, Schroedinger quantum mechanics. The…

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

We introduce a new operator representing the three-dimensional scalar curvature in loop quantum gravity. The operator is constructed by writing the Ricci scalar classically as a function of the Ashtekar variables and regularizing the…

General Relativity and Quantum Cosmology · Physics 2023-04-04 Ilkka Mäkinen

A quantum theory of gravity is described in the case of a positive cosmological constant in 3+1 dimensions. Both old and new results are described, which support the case that loop quantum gravity provides a satisfactory quantum theory of…

High Energy Physics - Theory · Physics 2007-05-23 Lee Smolin
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