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Related papers: Effective constraints of loop quantum gravity

200 papers

A consistent implementation of quantum gravity is expected to change the familiar notions of space, time and the propagation of matter in drastic ways. This will have consequences on very small scales, but also gives rise to correction…

General Relativity and Quantum Cosmology · Physics 2009-08-26 Martin Bojowald , Golam Mortuza Hossain , Mikhail Kagan , S. Shankaranarayanan

The primordial spectrum of cosmological tensor perturbations is considered as a possible probe of quantum gravity effects. Together with string theory, loop quantum gravity is one of the most promising frameworks to study quantum effects in…

General Relativity and Quantum Cosmology · Physics 2009-04-09 J. Grain , A. Barrau

We calculate the quantum corrections to the gauge-invariant gravitational potentials of spinning particles in flat space, induced by loops of both massive and massless matter fields of various types. While the corrections to the Newtonian…

High Energy Physics - Theory · Physics 2016-12-13 Markus B. Fröb

We explore the infrared limit of quantum gravity in presence of a cosmological constant or effective potential for scalar fields. For a positive effective scalar potential, one-loop perturbation theory around flat space is divergent due to…

General Relativity and Quantum Cosmology · Physics 2018-08-01 C. Wetterich

This article sheds new light on the problem of cosmological reduction in Loop Quantum Gravity. We critically analyze Quantum Reduced Loop Gravity -- an attempt to extract the cosmological sector of the full theory. We reconsider the…

General Relativity and Quantum Cosmology · Physics 2021-01-12 Jakub Bilski , Antonino Marciano

Canonical quantum gravity provides insights into the quantum dynamics as well as quantum geometry of space-time by its implications for constraints. Loop quantum gravity in particular requires specific corrections due to its quantization…

General Relativity and Quantum Cosmology · Physics 2015-05-14 Martin Bojowald

Loop quantum cosmology predicts that quantum gravity effects resolve the big-bang singularity and replace it by a cosmic bounce. Furthermore, loop quantum cosmology can also modify the form of primordial cosmological perturbations, for…

General Relativity and Quantum Cosmology · Physics 2017-06-28 Edward Wilson-Ewing

This article provides a cartoon of the quantization of General Relativity using the ideas of effective field theory. These ideas underpin the use of General Relativity as a theory from which precise predictions are possible, since they show…

General Relativity and Quantum Cosmology · Physics 2007-05-23 C. P. Burgess

We evaluated the scattering amplitude of neutral scalar particles at one-loop order in the context of effective field theory of quantum gravity in the presence of a cosmological constant. Our study suggests that quantum gravitational…

High Energy Physics - Theory · Physics 2013-12-02 A. C. Lehum

Starting from an heuristic approach to the semiclassical limit in loop quantum gravity, the construction of effective Hamiltonians describing Planck length corrections to the propagation of photons and spin 1/2 fermions, leading to modified…

High Energy Physics - Phenomenology · Physics 2016-11-09 Luis F. Urrutia

We compute the one-loop quantum corrections to the gravitational potentials of a spinning point particle in a de Sitter background, due to the vacuum polarisation induced by conformal fields in an effective field theory approach. We…

High Energy Physics - Theory · Physics 2017-04-19 Markus B. Fröb , Enric Verdaguer

A general nonperturvative loop quantization procedure for metric modified gravity is reviewed. As an example, this procedure is applied to scalar-tensor theories of gravity. The quantum kinematical framework of these theories is rigorously…

General Relativity and Quantum Cosmology · Physics 2013-04-09 Xiangdong Zhang , Yongge Ma

A finite and unitary nonlocal formulation of quantum gravity is applied to the cosmological constant problem. The entire functions in momentum space at the graviton-standard model particle loop vertices generate an exponential suppression…

General Relativity and Quantum Cosmology · Physics 2016-02-08 J. W. Moffat

We explore the possibility of a consistent cosmology based on the gauge-fixing independent running of the gravitational and cosmological constants ($G$ and $\Lambda$) in the framework of effective quantum gravity. In particular, their…

General Relativity and Quantum Cosmology · Physics 2024-04-30 Nicolas R. Bertini , Davi C. Rodrigues , Ilya L. Shapiro

We develop an effective framework for the $\bar\mu$ scheme of holonomy corrections motivated by loop quantum gravity for vacuum spherically symmetric space-times. This is done by imposing the areal gauge in the classical theory, and then…

General Relativity and Quantum Cosmology · Physics 2022-06-15 Jarod George Kelly , Robert Santacruz , Edward Wilson-Ewing

The quantum contributions to the gravitational action are relatively easy to calculate in the higher derivative sector of the theory. However, the applications to the post-inflationary cosmology and astrophysics require the corrections to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Julio C. Fabris , Paulo L. C. de Oliveira , Davi C. Rodrigues , Ilya L. Shapiro , A. M. Velasquez-Toribio

Loop quantum gravity and cosmology are reviewed with an emphasis on evaluating the dynamics, rather than constructing it. The three crucial parts of such an analysis are (i) deriving effective equations, (ii) controlling the theory's…

General Relativity and Quantum Cosmology · Physics 2011-01-31 Martin Bojowald

The cosmological primordial power spectrum is known to be one of the most promising observable to probe quantum gravity effects. In this article, we investigate how the tensor power spectrum is modified by Loop Quantum Gravity corrections.…

General Relativity and Quantum Cosmology · Physics 2010-04-06 J. Grain , T. Cailleteau , A. Barrau , A. Gorecki

Cosmological perturbations are generally described by quantum fields on (curved but) classical space-times. While this strategy has a large domain of validity, it can not be justified in the quantum gravity era where curvature and matter…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Ivan Agullo , Abhay Ashtekar , William Nelson

Degenerate geometrical configurations in quantum gravity are important to understand if the fate of classical singularities is to be revealed. However, not all degenerate configurations arise on an equal footing, and one must take into…

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