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Related papers: Time-Varying alpha and Particle Physics

200 papers

Endeavours of the unification of the four fundamental interactions have resulted in a development of theories having cosmological solutions in which low-energy limits of fundamental physical constants vary with time. The validity of such…

Astrophysics · Physics 2011-05-23 A. V. Ivanchik , A. Y. Potekhin , D. A. Varshalovich

It is well-known that $f(R)$ theories in Einstein frame is conformally equivalent to quintessence models in which the scalar field minimally couples with gravity. If there exists a matter system in Jordan frame, then it interacts with the…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Yousef Bisabr

The existing observational data on possible variations of fundamental physical constants (FPC) confirm more or less confidently only a variability of the fine structure constant $\alpha$ in space and time. A model construction method is…

General Relativity and Quantum Cosmology · Physics 2015-06-12 K. A. Bronnikov , V. N. Melnikov , S. G. Rubin , I. V. Svadkovsky

A brief note on the time variation of the fine structure constant $\alpha_{em}$; it is shown that such a variation should violate mass-energy conservation in the absence of proton decay.

Astrophysics · Physics 2007-05-23 G. R. Filewood

If the recent observations suggesting a time variation of the fine structure constant are correct, they imply the existence of an ultra light scalar particle. This particle inevitably couples to nucleons through the \alpha-dependence of…

High Energy Physics - Phenomenology · Physics 2009-11-07 Gia Dvali , Matias Zaldarriaga

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 consider classically scale-invariant theories with non-minimally coupled scalar fields, where the Planck mass and the hierarchy of physical scales are dynamically generated. The classical theories possess a fixed point, where scale…

High Energy Physics - Phenomenology · Physics 2017-05-03 K. Kannike , M. Raidal , C. Spethmann , H. Veermäe

Recently spatial as well as temporal variations of the fine structure constant alpha have been reported. We show that a "runaway domain wall", which arises for the scalar field potential without minima, can account for such variations…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-04 Takeshi Chiba , Masahide Yamaguchi

We review the observational information on the constancy of the fine structure constant alpha. We find that small improvements on the measurement of ^{187}Re lifetime can provide significant progress in exploring the range of variability…

Astrophysics · Physics 2009-11-07 G. Fiorentini , B. Ricci

A phenomenological model is proposed to explain the recent observed cosmological variation of the fine structure constant as an effect of the quantum vacuum, assuming a flat universe with cosmological constant $\Lambda$ in the cases…

Astrophysics · Physics 2010-12-17 Antonio F. Rañada

We work with a class of scalar extended theory of gravity that can drive the present cosmic acceleration as well as accommodate a mild cosmic variation of the fine structure constant $\alpha$. The motivation comes from a vintage theory…

General Relativity and Quantum Cosmology · Physics 2022-04-20 Soumya Chakrabarti

Time variation of fundamental constants would not be surprising in the framework of theories involving extra dimensions. The variation of any one constant is likely to be correlated with variations of others in a pattern that is diagnostic…

High Energy Physics - Phenomenology · Physics 2014-11-17 Paul Langacker

An oscillating, compact Friedmann universe with a massive conformally coupled scalar field is studied in the framework of quantum cosmology. The scalar field is treated as a perturbation and we look for solutions of the Wheeler-DeWitt…

General Relativity and Quantum Cosmology · Physics 2019-10-23 Thibault Damour , Alexander Vilenkin

We review some of the history and properties of theories for the variation of the gravitation and fine structure 'constants'. We highlight some general features of the cosmological models that exist in these theories with reference to…

General Relativity and Quantum Cosmology · Physics 2014-11-17 John D. Barrow

To explain the recently reported large-scale spatial variations of the fine structure constant $\alpha$, we apply some models of curvature-nonlinear multidimensional gravity. Under the reasonable assumption of slow changes of all quantities…

General Relativity and Quantum Cosmology · Physics 2013-12-31 K. A. Bronnikov , M. V. Skvortsova

We show that observational limits on the possible time variation of constants of Nature are significantly affected by allowing for both space and time variation. Bekenstein's generalisation of Maxwell's equations to allow for cosmological…

Astrophysics · Physics 2009-10-31 John D. Barrow , Chris O'Toole

The fine-structure constant alpha approximately 1/137 is traditionally regarded as a fundamental dimensionless parameter. I argue instead that alpha is a scaled quantity that arises only where the structural scales contributed by classical…

History and Philosophy of Physics · Physics 2025-12-09 Harry Sticker

We present a theoretical calculation on the time-variability of the fine-structure constant to fit the result of the recent precise analysis of the measurement of the QSO absorption lines. We find the parameters and initial values of the…

Astrophysics · Physics 2008-11-26 Yasunori Fujii

The variation of fine structure constant with the variation of velocity of light has been studied considering contribution to the permeability and permittivity of the vacuum and incorporating contribution of fractal potential originated…

General Physics · Physics 2017-06-09 A. Bhattacharya , R. Saha , R. Ghosh

We derive the formulae for the time variation of the gravitational "constant" G and of the fine structure "constant" \alpha in various models with extra dimensions and analyze their consistency with the available observational data for…

Astrophysics · Physics 2009-11-10 P. Loren-Aguilar , E. Garcia-Berro , J. Isern , Yu. A. Kubyshin