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We show that the Horava theory for the completion of General Relativity at UV scales can be interpreted as a gauge fixed theory, and it can be extended to an invariant theory under the full group of four-dimensional diffeomorphisms. In this…

High Energy Physics - Theory · Physics 2015-05-13 Cristiano Germani , Alex Kehagias , Konstadinos Sfetsos

A model is proposed to demonstrate that classical general relativity can emerge from loop quantum gravity, in a relational description of gravitational field in terms of coordinates given by matter. Local Dirac observables and coherent…

General Relativity and Quantum Cosmology · Physics 2011-03-29 Chun-Yen Lin

We consider two concepts often discussed as significant features of general relativity (particularly when contrasted with the other forces of the Standard Model): background independence and diffeomorphism invariance. We remind the reader…

General Relativity and Quantum Cosmology · Physics 2015-12-14 Casey Cartwright , Alex Flournoy

The infinite group of deformed diffeomorphisms of the spacetime continuum is put into the basis of the gauge theory of gravity. This gives rise to some new ways for unification of gravity with other gauge interactions.

General Relativity and Quantum Cosmology · Physics 2018-03-07 S. E. Samokhvalov , V. S. Vanyashin

In this work we use generalized deformed gauge groups for investigation of symmetry of general relativity (GR). GR is formulated in generalized reference frames, which are represented by (anholonomic in general case) affine frame fields.…

General Relativity and Quantum Cosmology · Physics 2020-06-09 S. E. Samokhvalov

It is well known that in a generally covariant gravitational theory the choice of spacetime scalars as coordinates yields phase-space observables (or "invariants"). However their relation to the symmetry group of diffeomorphism…

General Relativity and Quantum Cosmology · Physics 2009-11-19 J. M. Pons , D. C. Salisbury , K. A. Sundermeyer

The construction of Dirac observables, that is gauge invariant objects, in General Relativity is technically more complicated than in other gauge theories such as the standard model due to its more complicated gauge group which is closely…

General Relativity and Quantum Cosmology · Physics 2014-11-20 K. Giesel , J. Tambornino , T. Thiemann

We study how the problem of observables is fully resolved for background independent theories defined on finite graphs. We argue the correct analogue of coordinate independence is the invariance under changes of graph labels, a kind of…

General Relativity and Quantum Cosmology · Physics 2025-08-05 Emil Broukal , Andrea Di Biagio , Eugenio Bianchi , Marios Christodoulou

The four-dimensional gauge group of general relativity corresponds to arbitrary coordinate transformations on a four-manifold. Theories of gravity with a dynamical structure remarkably like Einstein's theory can be obtained on the basis of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Julian Barbour , Niall O Murchadha

We discuss the issue of observables in general-relativistic perturbation theory, adopting the view that any observable in general relativity is represented by a scalar field on spacetime. In the context of perturbation theory, an observable…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Marco Bruni , Sebastiano Sonego

Quantum Relativity is supposed to be a new theory, which locally is a deformation of Special Relativity, and globally it is a background independent theory including the main ideas of General Relativity, with hindsight from Quantum Theory.…

General Physics · Physics 2010-06-08 Lucian M Ionescu

As in the case of the other gauge field theories, there is so called ``gauge'' also in general relativity. This ``gauge'' is unphysical degree of freedom. There are two kinds of ``gauges'' in general relativity. These are called the first-…

General Relativity and Quantum Cosmology · Physics 2007-11-08 Kouji Nakamura

Change and local spatial variation are missing in canonical General Relativity's observables as usually defined, part of the problem of time. Definitions can be tested using equivalent formulations, non-gauge and gauge, because they must…

General Relativity and Quantum Cosmology · Physics 2017-03-06 J. Brian Pitts

We consider general relativity with a cosmological constant as a perturbative expansion around a completely solvable diffeomorphism invariant field theory. This theory is the $\Lambda\to\infty$ limit of general relativity. This allows an…

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

The algebra of observables associated with a quantum field theory is invariant under the connected component of the Lorentz group and under parity reversal, but it is not invariant under time reversal. If we take general covariance…

Quantum Physics · Physics 2008-10-28 Peter Morgan

We explore the hypothesis that the set of symmetries enjoyed by the theory that describes gravity is not the full group of diffeomorphisms Diff(M), as in General Relativity, but a maximal subgroup of it, TransverseDiff(M), with its elements…

High Energy Physics - Theory · Physics 2015-05-18 J. J. Lopez-Villarejo

Einstein's General Relativity (GR) is a dynamical theory of the spacetime metric. We describe an approach in which GR becomes an SU(2) gauge theory. We start at the linearised level and show how a gauge theoretic Lagrangian for…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Kirill Krasnov

The questions of describing observables and observation in quantum gravity appear to be centrally important to its physics. A relational approach holds significant promise, and a classification of different types of relational observables…

High Energy Physics - Theory · Physics 2025-06-13 Steven B. Giddings

We investigate a possible unified theory of all interactions which is based only on fundamental spinor fields. The vielbein and metric arise as composite objects. The effective quantum gravitational theory can lead to a modification of…

High Energy Physics - Theory · Physics 2009-11-10 C. Wetterich

(Abridged Abstract) This paper deals with a number of technical achievements that are instrumental for a dis-solution of the so-called {\it Hole Argument} in general relativity. The work is carried through in metric gravity for the class of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Luca Lusanna , Massimo Pauri