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Related papers: Emergent modified gravity: Covariance regained

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We argue that a conformally invariant extension of general relativity coupled to the Standard Model is the fundamental theory that needs to be quantized. We show that it can be treated by loop quantum gravity techniques. Through a gauge…

General Relativity and Quantum Cosmology · Physics 2017-01-24 Miguel Campiglia , Rodolfo Gambini , Jorge Pullin

Quantum Mechanics is revisited as the appropriate theoretical framework for the description of the outcome of experiments that rely on the use of classical devices. In particular, it is emphasized that the limitations on the measurability…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Giovanni Amelino-Camelia

We present a 4-dimensional generally covariant gauge theory which leads to the Gauss constraint but lacks both the Hamiltonian and spatial diffeomorphism constraints. The canonical theory therefore resembles Yang-Mills theory without the…

General Relativity and Quantum Cosmology · Physics 2024-02-23 Viqar Husain , Hassan Mehmood

A set of diverse but mutually consistent results obtained in different settings has spawned a new view of loop quantum gravity and its physical implications, based on the interplay of operator calculations and effective theory: Quantum…

General Relativity and Quantum Cosmology · Physics 2012-12-27 Martin Bojowald

A new approach to quantum gravity is presented based on a nonlinear quantization scheme for canonical field theories with an implicitly defined Hamiltonian. The constant mean curvature foliation is employed to eliminate the momentum…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Charles H-T Wang

In this paper the novel features of Yokoyama gaugeon formalism are stressed out for the theory of perturbative quantum gravity in Einstein curved spacetime. The quantum gauge transformations for the theory of perturbative gravity are…

General Relativity and Quantum Cosmology · Physics 2014-03-26 Sudhaker Upadhyay

The field equations in modified gravity theories possess an important decoupling property with respect to certain classes of nonholonomic frames. This allows us to construct generic off--diagonal solutions depending on all spacetime…

General Relativity and Quantum Cosmology · Physics 2015-02-23 Sergiu I. Vacaru

The task of quantizing gravity is compared with Einstein's relativization of gravity. The philosophical and physical foundations of general relativity are briefly reviewed. The Ehlers-Pirani-Schild scheme of operationally determining the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Jeeva S. Anandan

In it's usual presentation, classical mechanics appears to give time a very special role. But it is well known that mechanics can be formulated so as to treat the time variable on the same footing as the other variables in the extended…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Michael Reisenberger , Carlo Rovelli

We reformulate the general theory of relativity in the language of Riemann-Cartan geometry. We start from the assumption that the space-time can be described as a non-Riemannian manifold, which, in addition to the metric field, is endowed…

General Relativity and Quantum Cosmology · Physics 2015-06-12 J. B. Fonseca-Neto , C. Romero , S. P. G. Martinez

A generalised canonical formulation of gravity is devised for foliations of spacetime with codimension $n\ge1$. The new formalism retains n-dimensional covariance and is especially suited to 2+2 decompositions of spacetime. It is also…

General Relativity and Quantum Cosmology · Physics 2009-10-30 James D. E. Grant , Ian G. Moss

We consider a specific Hamiltonian formulation of the Teleparallel Equivalent of General Relativity, where the canonical variables are expressed by means of differential forms. We show that some ``position'' variables of this formulation…

General Relativity and Quantum Cosmology · Physics 2024-10-24 Andrzej Okolow

The first part of the series formulates the Einstein-Cartan theory in the covariant hamiltonian framework. The first section revises the general multisymplectic approach and introduces the notion of the d-jet bundles. Since the whole…

General Relativity and Quantum Cosmology · Physics 2018-03-16 Marián Pilc

We introduce the natural lift of spacetime diffeomorphisms for conformal gravity and discuss the physical equivalence between the natural and gauge natural structure of the theory. Accordingly, we argue that conformal transformations must…

General Relativity and Quantum Cosmology · Physics 2015-06-22 M. Campigotto , L. Fatibene

We suggest commutation relations for a quantum measure. In one version of these relations, the right-hand side takes account of the presence of curvature of space; in the simplest case, this yields the action of general relativity. We…

General Relativity and Quantum Cosmology · Physics 2024-01-01 Vladimir Dzhunushaliev , Vladimir Folomeev

Emergent modified gravity is a canonical theory based on general covariance where the spacetime is not fundamental, but rather an emergent object. This feature allows for modifications of the classical theory and can be used to model new…

General Relativity and Quantum Cosmology · Physics 2024-02-06 Erick I. Duque

On one popular view, the general covariance of gravity implies that change is relational in a strong sense, such that all it is for a physical degree of freedom to change is for it to vary with regard to a second physical degree of freedom.…

General Relativity and Quantum Cosmology · Physics 2018-01-18 Sean Gryb , Karim Thebault

Several quantum gravity and string theory thought experiments indicate that the Heisenberg uncertainty relations get modified at the Planck scale so that a minimal length do arises. This modification may imply a modification of the…

Classical Physics · Physics 2020-09-28 O. I. Chashchina , A. Sen , Z. K. Silagadze

Versions of parameterized pseudo-Newtonian gravity theories specially designed for cosmology have been introduced in recent cosmology literature. The modifications demand a zero-pressure fluid in the context of versions of modified…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jai-chan Hwang , Hyerim Noh , Chan-Gyung Park

"Physical theories of fundamental significance tend to be gauge theories. These are theories in which the physical system being dealt with is described by more variables than there are physically independent degree of freedom. The…

Classical Physics · Physics 2007-05-23 Germain Rousseaux