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Related papers: Quantum gravity without vacuum dispersion

200 papers

Causal Dynamical Triangulations (CDT) is a proposal for a theory of quantum gravity, which implements a path-integral quantization of gravity as the continuum limit of a sum over piecewise flat spacetime geometries. We use Monte Carlo…

High Energy Physics - Theory · Physics 2012-06-25 J. Ambjorn , S. Jordan , J. Jurkiewicz , R. Loll

A possible way to capture the effects of quantum gravity in spacetime at a mesoscopic scale, for relatively low energies, is through an energy dependent metric, such that particles with different energies probe different spacetimes. In this…

General Relativity and Quantum Cosmology · Physics 2022-10-12 G. Chirco , S. Liberati , J. J. Relancio

We replace the usual Hamiltonian constraint of quantum gravity H|psi>=0 by a weaker one <psi|H|psi>=0. This allows |psi> to satisfy the time-dependent functional Schrodinger equation. In general, only the phase of the wave function appears…

General Relativity and Quantum Cosmology · Physics 2007-05-23 H. Nikolic

We revisit a supersymmetric string model for space-time foam, in which bosonic open-string states, such as photons, can possess quantum-gravity-induced velocity fluctuations in vacuum. We argue that the suggestion of light speed variation…

High Energy Physics - Phenomenology · Physics 2021-08-27 Chengyi Li , Bo-Qiang Ma

Although we lack complete understanding of quantum aspects of gravitation, it is usually agreed, using general arguments, that a final quantum gravity theory will endow space and time with some (fundamental or effective) notion of…

Quantum Physics · Physics 2024-05-28 Daniel A. Turolla Vanzella

The principles of quantum field theory in flat spacetime suggest that gravity is mediated by a massless particle with helicity $\pm2$, the so-called graviton. It is regarded as textbook knowledge that, when the self-coupling of a particle…

General Relativity and Quantum Cosmology · Physics 2018-09-25 Carlos Barceló , Raúl Carballo-Rubio , Luis J. Garay

We show that an analog of the physics at the Planck scale can be found in the propagation of tightly focused laser beams. Various equations that occur in generalized quantum mechanics are formally identical to those describing the nonlinear…

Optics · Physics 2014-06-26 Claudio Conti

To facilitate the search for a continuum limit of causal dynamical triangulations, Ambjorn, Coumbe, Gizbert-Studnicki, and Jurkiewicz recently reported measurements of the lattice spacing as a function of the bare couplings. Although these…

General Relativity and Quantum Cosmology · Physics 2016-04-08 Joshua H. Cooperman

The noncommutativity of the space-time had important implications for the very early Universe, when its size was of the order of the Planck length. An important implication of this effect is the deformation of the standard dispersion…

General Relativity and Quantum Cosmology · Physics 2018-10-09 Yunxin Ye , Tiberiu Harko , Shi-Dong Liang

The idea that the cosmological term, Lambda, should be a time dependent quantity in cosmology is a most natural one. It is difficult to conceive an expanding universe with a strictly constant vacuum energy density, namely one that has…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 Joan Sola

It is well known that in quantum gravity, the very geometry of space and time is subject to continual fluctuation. The mathematical formulation for this old theory is still lacking. This article formulates this more than forty-year-old…

General Relativity and Quantum Cosmology · Physics 2024-09-27 Behzad Tajahmad

In the investigation and resolution of the cosmological constant problem the inclusion of the dynamics of quantum gravity can be a crucial step. In this work we suggest that the quantum constraints in a canonical theory of gravity can…

High Energy Physics - Theory · Physics 2013-04-23 Jan Govaerts , Simone Zonetti

We reinterpret the spectral dimension of spacetimes as the scaling of an effective self-energy transition amplitude in quantum field theory (QFT), when the system is probed at a given resolution. This picture has four main advantages: (a)…

High Energy Physics - Theory · Physics 2016-04-13 Gianluca Calcagni , Leonardo Modesto , Giuseppe Nardelli

One of the main results of Scale Relativity as regards the foundation of quantum mechanics is its explanation of the origin of the complex nature of the wave function. The Scale Relativity theory introduces an explicit dependence of…

General Physics · Physics 2013-11-13 Laurent Nottale , Marie-Noëlle Célérier

The quantum gravity is formulated based on principle of local gauge invariance. The model discussed in this paper has local gravitational gauge symmetry and gravitational field is represented by gauge field. In leading order approximation,…

High Energy Physics - Theory · Physics 2007-05-23 Ning Wu

Cosmological linear perturbation theory predicts that the peculiar velocity $V(x)$ and the matter overdensity $\delta(x)$ at a same point $x$ are statistically independent quantities, as log as the initial density fluctuations are random…

Astrophysics · Physics 2009-10-31 Naoki Seto

We unify all existing results on the change of the speed of low--energy photons due to modifications of the vacuum, finding that it is given by a universal constant times the quotient of the difference of energy densities between the usual…

High Energy Physics - Theory · Physics 2016-09-06 J. I. Latorre , P. Pascual , R. Tarrach

In this talk, I present a theory of quantum gravity beyond Einstein. The theory is established based on spinnic and scaling gauge symmetries by treating the gravitational force on the same footing as the electroweak and strong forces. A…

High Energy Physics - Theory · Physics 2015-11-04 Yue-Liang Wu

We make the first steps towards a generic theory for energy spreading and quantum dissipation. The Wall formula for the calculation of friction in nuclear physics and the Drude formula for the calculation of conductivity in mesoscopic…

Condensed Matter · Physics 2009-10-31 Doron Cohen

The cosmological phenomenology of gravity is typically studied in two limits: relativistic perturbation theory (on large scales) and Newtonian gravity (required for smaller, non-linear, scales). Traditional approaches to model-independent…

General Relativity and Quantum Cosmology · Physics 2020-07-21 Daniel B Thomas