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Related papers: Gravitons and Lightcone Fluctuations

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Finding signatures of quantum gravity in cosmological observations is now actively pursued both from the theoretical and the experimental side. Recent work has concentrated on finding signatures of light-cone fluctuations in the CMB.…

General Relativity and Quantum Cosmology · Physics 2009-11-11 David Polarski , Philippe Roche

Quantum fields possess zero-point or vacuum fluctuations which induce mechanical effects, namely generalised Casimir forces, on any scatterer. Symmetries of vacuum therefore raise fundamental questions when confronted with the principle of…

Quantum Physics · Physics 2007-05-23 Marc-Thierry Jaekel , Serge Reynaud

The quantum fluctuations of the geodesic deviation equation in a flat background spacetime are discussed. We calculate the resulting mean squared fluctuations in the relative velocity and separation of test particles. The effect of these…

General Relativity and Quantum Cosmology · Physics 2018-10-10 H. S. Vieira , L. H. Ford , V. B. Bezerra

We compute the metric fluctuations induced by a turbulent energy-matter tensor within the first order Post-Minkowskian approximation. It is found that the turbulent energy cascade can in principle interfere with the process of black hole…

General Relativity and Quantum Cosmology · Physics 2022-11-16 Donato Bini , Stuart Kauffman , Sauro Succi , Pablo G. Tello

We consider a model of modified gravity from the nonperturbative quantization of a metric. We obtain the modified gravitational field equations and the modified conservational equations. We apply it to the FLRW spacetime and find that due…

General Relativity and Quantum Cosmology · Physics 2016-05-20 Rong-Jia Yang

Zero-point fluctuations are a universal consequence of quantum theory. Vacuum fluctuations of electromagnetic field have provided crucial evidence and guidance for QED as a successful quantum field theory with a defining gauge symmetry…

General Relativity and Quantum Cosmology · Physics 2021-05-12 Charles H. -T. Wang , Melania Mieczkowska

We apply the new quantization scheme outlined in Phys. Rev. D102 (2020) 125001 to explore the influence which quantum vacuum fluctuations of the spacetime metric exert on the universes of Quantum Einstein Gravity, which is regarded an…

High Energy Physics - Theory · Physics 2021-12-22 Maximilian Becker , Martin Reuter

It is generally expected that quantum gravity affects the structure of space-time by introducing stochastic fluctuations in the geometry, and, ultimately, in the measurements of four-distances and four-momenta.These fluctuations may induce…

Astrophysics · Physics 2007-05-23 R. Aloisio , P. Blasi , A. Galante , P. L. Ghia , A. F. Grillo

We investigate the effects of light-cone fluctuations over the renormalized vacuum expectation value of the stress-energy tensor of a real massless minimally coupled scalar field defined in a ($d+1$)-dimensional flat space-time with…

High Energy Physics - Theory · Physics 2014-05-27 V. A. De Lorenci , G. Menezes , N. F. Svaiter

It was shown that quantum metric fluctuations smear out the singularities of Green's functions on the light cone [1], but it does not remove other ultraviolet divergences of quantum field theory. We have proved that the quantum field theory…

General Relativity and Quantum Cosmology · Physics 2011-06-02 S. Rouhani , M. V. Takook

I present a theory of quantum gravity based on the principle of gravitational energy fluctuations. Gravitational energy fluctuations -- gravitons -- are responsible for elastic scattering of subatomic particles. Such scattering corresponds…

General Relativity and Quantum Cosmology · Physics 2010-09-08 Max I. Fomitchev

Vacuum fluctuations of quantum fields are altered in presence of a strong gravitational background, with important physical consequences. We argue that a non-trivial spacetime geometry can act as an optically active medium for quantum…

General Relativity and Quantum Cosmology · Physics 2017-11-22 Ivan Agullo , Adrian del Rio , Jose Navarro-Salas

We discuss effects of loss of coherence in low energy quantum systems caused by or related to gravitation, referred to as gravitational decoherence. These effects, resulting from random metric fluctuations, for instance, promise to be…

Quantum Physics · Physics 2017-09-26 Angelo Bassi , André Großardt , Hendrik Ulbricht

The problem of formulating a fully consistent quantum gravity theory (QGT) has not yet been solved. Even before we are able to work out the details of a complete theory, however, we do know some important qualitative features to be expected…

Astrophysics · Physics 2007-05-23 Rosanne Di Stefano , L. H. Ford , Hongwei Yu , D. J. Fixsen

Electromagnetic and gravitational radiation do not propagate solely on the null cone in a generic curved spacetime. They develop "tails," traveling at all speeds equal to and less than unity. If sizeable, this off-the-null-cone effect could…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 Yi-Zen Chu , Glenn D. Starkman

We study fluctuations and correlations between spacial regions, generated by the primordial quantum gravitational phase of the universe. We do so by a numerical evaluation of Lorentzian amplitudes in Loop Quantum Gravity, in a…

General Relativity and Quantum Cosmology · Physics 2021-06-17 Francesco Gozzini , Francesca Vidotto

One of the most common expectations of a quantum theory of gravity is that space-time is uncertain or fluctuating at microscopic scales, making it a stochastic medium for particle propagation. Particles traversing this space-time may…

High Energy Physics - Phenomenology · Physics 2022-01-19 Thomas Stuttard

We derive some of the central equations governing quantum fluctuations in gravitational waves, making use of general relativity as a sensible effective quantum theory at large distances. We begin with a review of classical gravitational…

General Relativity and Quantum Cosmology · Physics 2023-03-06 Mark P. Hertzberg , Jacob A. Litterer

Quantum fluctuations impose fundamental limits on measurement and space-time probing. Although using optimised probe fields can allow to push sensitivity in a position measurement beyond the "standard quantum limit", quantum fluctuations of…

Quantum Physics · Physics 2009-10-28 Marc-Thierry Jaekel , Serge Reynaud

Quantum gravity is quite elusive at the experimental level; thus a lot of interest has been raised by recent searches for quantum gravity effects in the propagation of light from distant sources, like gamma ray bursters and active galactic…

General Physics · Physics 2010-12-03 Stefano Ansoldi , Edoardo Milotti