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Related papers: Spatial Variations of Fundamental Constants

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The tests of the constancy of the fundamental constants are tests of the local position invariance and thus of the equivalence principle. We summarize the various constraints that have been obtained and then describe the connection between…

General Relativity and Quantum Cosmology · Physics 2015-05-13 Jean-Philippe Uzan

Testing the cosmological variation of fundamental constants of Nature can provide valuable insights into new physics scenarios. While many such constraints have been derived for Standard Model coupling constants and masses, the $\bar\theta$…

High Energy Physics - Phenomenology · Physics 2022-10-13 Hooman Davoudiasl , Julia Gehrlein , Robert Szafron

Rolling tachyon field models are among the candidates suggested as explanations for the recent acceleration of the Universe. In these models the field is expected to interact with gauge fields and lead to variations of the fine-structure…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-28 C. J. A. P. Martins , F. M. O. Moucherek

We have investigated some cosmological consequences of variation of the fine structure constant, $\alpha$, in the context of the Bekenstein-Sandvik-Barrow-Magueijo (BSBM) model. In this context, such a variation is attributed to electric…

General Relativity and Quantum Cosmology · Physics 2021-08-10 Yousef Bisabr

We review recent progress in the study of varying constants and attempts to explain the observed values of the fundamental physical constants. We describe the variation of $G$ in Newtonian and relativistic scalar-tensor gravity theories. We…

General Relativity and Quantum Cosmology · Physics 2009-09-25 John D. Barrow

Scalar field dynamics may give rise to a nonzero cosmological variation of fundamental constants. Within different scenarios based on the unification of gauge couplings, the various claimed observations and bounds may be combined in order…

High Energy Physics - Phenomenology · Physics 2010-04-21 Thomas Dent , Steffen Stern , Christof Wetterich

We advance the viewpoint that only relevant modes of the vacuum fluctuations, namely, with wavelengths conditioned by the size, homogeneity, geometry and topology of the Universe, do contribute into the cosmological constant. A formula is…

Astrophysics · Physics 2014-10-13 V. G. Gurzadyan , She-Sheng Xue

If the reported measurements of the time variation of the fine structure constant from observations of distant QSOs are correct, combined with the Oklo limit they would strongly constrain the class of the quintessence potential. If these…

High Energy Physics - Phenomenology · Physics 2009-11-07 Takeshi Chiba , Kazunori Kohri

Last year I talked at this meeting about a possible time dependence of the QCD coupling constant $\alpha_s$. This year I shall look into the problem once more, without fully repeating the arguments given last year. Astrophysical indications…

High Energy Physics - Phenomenology · Physics 2009-11-10 Harald Fritzsch

We describe the results of a search for time variability of the fine structure constant, alpha, using absorption systems in the spectra of distant quasars. Three large optical datasets and two 21cm/mm absorption systems provide four…

Astrophysical indications that the fine structure constant has undergone a small time variation during the cosmological evolution are discussed within the framework of the standard model of the electroweak and strong interactions and of…

High Energy Physics - Phenomenology · Physics 2009-11-07 Xavier Calmet , Harald Fritzsch

A number of positive and null results on the time variation of fundamental constants have been reported. It is difficult to judge whether or not these claims are mutually consistent, since the observable quantities depend on several…

High Energy Physics - Phenomenology · Physics 2009-02-23 Thomas Dent , Steffen Stern , Christof Wetterich

The Cosmic Microwave Background anisotropies provide a unique opportunity to constrain simultaneous variations of the fine-structure constant $\alpha$ and Newton's gravitational constant $G$. Those correlated variations are possible in a…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-28 C. J. A. P. Martins , Eloisa Menegoni , Silvia Galli , Gianpiero Mangano , Alessandro Melchiorri

We determine the behaviour of a time-varying fine structure 'constant' $\alpha (t)$ during the early and late phases of universes dominated by the kinetic energy of changing $\alpha (t)$, radiation, dust, curvature, and lambda,…

Astrophysics · Physics 2008-11-26 J. D. Barrow , H. B. Sandvik , J. Magueijo

There is no doubt that the field of Fundamental Constants in Physics and Their Time Variation is one of the hottest subjects in modern theoretical and experimental physics, with potential implications in all fundamental areas of physics…

High Energy Physics - Phenomenology · Physics 2015-07-14 Joan Solà

Fundamental physical constants play important role in modern physics. Studies of their variation can open an interface to new physics. An overview of different approaches to a search for such variations is presented as well as possible…

Atomic Physics · Physics 2007-05-23 Savely G. Karshenboim

We discuss how laboratory experiments can be used to place constraints on possible variations of the fine structure constant alpha in the observationally relevant redshift interval z ~= 0 - 5, within a rather general theoretical framework.…

Astrophysics · Physics 2009-10-30 Mario Livio , Massimo Stiavelli

We consider implications of the microscopic dynamics of spacetime for the evolution of cosmological models. We argue that quantum geometry effects may lead to stochastic fluctuations of the gravitational constant, which is thus considered…

General Relativity and Quantum Cosmology · Physics 2022-09-15 Marco de Cesare , Fedele Lizzi , Mairi Sakellariadou

By employing Dirac LNH, and a further generalization by Berman (GLNH), we estimate how should vary the total number of nucleons, the energy density, Newton Gravitational constant, the cosmological constant, the magnetic permeability and…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marcelo S. Berman , Luis A. Trevisan

By measuring the fundamental constants in astrophysical objects one can test basic physical principles as space-time invariance of physical laws along with probing the applicability limits of the standard model of particle physics. The…

Instrumentation and Methods for Astrophysics · Physics 2016-03-07 S. A. Levshakov