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Related papers: Kinematical Uniqueness of Loop Quantum Gravity

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Two sets of spatially diffeomorphism invariant operators are constructed in the loop representation formulation of quantum gravity. This is done by coupling general relativity to an anti- symmetric tensor gauge field and using that field to…

General Relativity and Quantum Cosmology · Physics 2009-10-22 Lee Smolin

In this review we discuss emergence of unimodular gravity (or, more precisely, Weyl transverse gravity) from thermodynamics of spacetime. By analyzing three different ways to obtain gravitational equations of motion by thermodynamic…

General Relativity and Quantum Cosmology · Physics 2022-04-19 Ana Alonso-Serrano , Marek Liška

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 brief note (written as a lengthy letter), we describe the construction of a representation for the Weyl-algebra underlying Loop Quantum Geometry constructed from a diffeomorphism variant state, which corresponds to a ''condensate''…

General Relativity and Quantum Cosmology · Physics 2007-09-24 Tim A. Koslowski

A new framework of loop quantization that assimilates conformal and scale invariance is constructed and is found to be applicable to a large class of physically important theories of gravity and gravity-matter systems. They include general…

General Relativity and Quantum Cosmology · Physics 2019-01-02 Charles H. -T. Wang , Daniel P. F. Rodrigues

We study a model for quantum gravity on a circle in which the notion of a classical metric tensor is replaced by a quantum metric with an inhomogeneous transformation law under diffeomorphisms. This transformation law corresponds to the…

General Relativity and Quantum Cosmology · Physics 2010-04-06 R. J. Henderson , S. G. Rajeev

The representation theory of non-centrally extended Lie algebras of Noether symmetries, including spacetime diffeomorphisms and reparametrizations of the observer's trajectory, has recently been developped. It naturally solves some…

General Relativity and Quantum Cosmology · Physics 2007-05-23 T. A. Larsson

The theorem by Lewandowski et al. stating uniqueness of a diffeomorphism invariant state on an algebra of quantum observables for background independent theories of connections is based on some technical assumptions imposed on the algebra…

Mathematical Physics · Physics 2010-10-25 Michal Dziendzikowski , Andrzej Okolow

We continue an analysis of representations of cylindrical functions and fluxes which are commonly used as elementary variables of Loop Quantum Gravity. We consider an arbitrary principal bundle of a compact connected structure group and…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Andrzej Okolow , Jerzy Lewandowski

We formally prove the existence of a quantization procedure that makes the path integral of a general diffeomorphism-invariant theory of gravity, with fixed total spacetime volume, equivalent to that of its unimodular version. This is…

General Relativity and Quantum Cosmology · Physics 2022-01-05 Gustavo P. de Brito , Oleg Melichev , Roberto Percacci , Antonio D. Pereira

In this paper we calculate the kinematical quantities of the Raychaudhuri equations, to characterize a congruence of time-like integral curves, according to the vacuum radial solution of Weyl theory of gravity. Also the corresponding flows…

General Physics · Physics 2019-05-09 Mohsen Fathi

We give a standard introduction to loop quantum gravity, from the ADM variables to spin network states. We include a discussion on quantum geometry on a fixed graph and its relation to a discrete approximation of general relativity.

General Relativity and Quantum Cosmology · Physics 2010-09-21 Pietro Doná , Simone Speziale

The renormalization structure of two-dimensional quantum gravity is investigated, in a covariant gauge. One-loop divergences of the effective action are calculated. All the surface divergent terms are taken into account, thus completing…

High Energy Physics - Theory · Physics 2009-09-17 E. Elizalde , S. Naftulin , S. D. Odintsov

The paper concerns the fictitious entanglement of the so-called ``singularities'' in problems, pertaining to quantum gravity, due, in point of fact, to the way we try to employ, in that context, differential geometry, the latter being…

General Physics · Physics 2007-05-23 Anastasios Mallios

The Weyl algebra A of continuous functions and exponentiated fluxes, introduced by Ashtekar, Lewandowski and others, in quantum geometry is studied. It is shown that, in the piecewise analytic category, every regular representation of A…

Mathematical Physics · Physics 2009-05-05 Christian Fleischhack

We reassess the problem of separability of the kinematic Hilbert space in loop quantum gravity under a new mathematical point of view. We use the formalism of frames, a tool used in signal analysis, in order to remove the redundancy of the…

General Relativity and Quantum Cosmology · Physics 2016-10-31 Bruno Carvalho , Daniel H. T. Franco

As part of a wider study of coherent states in (loop) quantum gravity, we introduce a modification to the standard construction, based on the recently introduced (non-commutative) flux representation. The resulting quantum states have some…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Daniele Oriti , Roberto Pereira , Lorenzo Sindoni

We show that Vassiliev invariants of knots, appropriately generalized to the spin network context, are loop differentiable in spite of being diffeomorphism invariant. This opens the possibility of defining rigorously the constraints of…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Rodolfo Gambini , Jorge Griego , Jorge Pullin

Loop Quantum Gravity is now a well established approach to quantum gravity. One of the main challenges still faced by the theory is constructing a consistent dynamics which would lead back to the standard dynamics of the gravitational field…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Enrique F. Borja , Jacobo Díaz-Polo , Laurent Freidel , Iñaki Garay , Etera R. Livine

We propose a model for the quantum theory of gravity. the model has diffeomorphism invariance, a natural length scale, and (plausibly) propagating modes. in the new addendum, we alter the model in a way which makes the propagating modes…

General Relativity and Quantum Cosmology · Physics 2008-02-03 Louis Crane