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We study the evolution of the fine-structure constant, $\alpha$, induced by non-linear density perturbations in the context of the simplest class of quintessence models with a non-minimal coupling to the electromagnetic field, in which the…

Astrophysics · Physics 2009-11-13 P. P. Avelino , C. J. A. P. Martins , J. Menezes , C. Santos

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 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 data from the QSO absorption lines indicating a nonzero time-variability of the fine-structure constant has been re-analyzed on the basis of a "damped-oscillator" fit, as motivated by the same type of behavior of a scalar field,…

Astrophysics · Physics 2015-06-24 Yasunori Fujii

The recent evidence for a cosmological evolution of the fine structure constant \alpha=e^2/\hbar c found from an analysis of absorption systems in the spectra of distant quasars, is modelled by a cosmological scenario in which it is assumed…

Astrophysics · Physics 2007-05-23 J. W. Moffat

Higher-dimensional theories have the remarkable feature of predicting a time (and hence redshift) dependence of the `fundamental' four dimensional constants on cosmological timescales. In this paper we update the bounds on a possible…

In the present work, we consider the cosmological constant model $\Lambda\propto\alpha^{-6}$, which is well motivated from three independent approaches. As is well known, the hint of varying fine structure constant $\alpha$ was found in…

General Relativity and Quantum Cosmology · Physics 2017-01-10 Hao Wei , Xiao-Bo Zou , Hong-Yu Li , Dong-Ze Xue

Theories unifying gravity and other interactions suggest the possibility of spatial and temporal variation of physical ``constants'' in the Universe. Detection of high redshift absorption systems intersecting the sight lines towards distant…

Astrophysics · Physics 2009-08-18 V. A. Dzuba , V. V. Flambaum , M. T. Murphy , J. K. Webb

Dynamical models of dark energy can imply that the fine structure constant $\alpha$ varies over cosmological time scales. Data on shifts in resonance energies $E_r$ from the Oklo natural fission reactor have been used to place restrictive…

Nuclear Theory · Physics 2015-10-13 Leila Hamdan , Edward D. Davis

In present paper we evaluate the fine structure constant variation, that should take place as the Universe expands and its curvature is changed adiabatically. Such variation of the fine structure constant is attributed to an energy losses…

General Physics · Physics 2020-12-15 Anton A. Lipovka , Ivan A. Cardenas

The cosmological evolution of a quintessence-like scalar field, phi, coupled to matter and gauge fields leads to effective modifications of the coupling constants and particle masses over time. We analyze a class of models where the scalar…

Astrophysics · Physics 2009-09-15 Seokcheon Lee , Keith A. Olive , Maxim Pospelov

Cosmological dark energy is a natural source of variation of the fine structure constant. Using a model-independent approach we show that once general assumptions about the alpha-varying interactions are made, astronomical probes of its…

Astrophysics · Physics 2015-06-24 David Parkinson , Bruce A. Bassett , John D. Barrow

We consider a long range scalar force that mainly couples to dark matter and unstable Standard Model states, like the muon, with tiny strength. Probing this type of force would present a challenge to observations. We point out that the…

High Energy Physics - Phenomenology · Physics 2018-12-13 Hooman Davoudiasl , Pier Paolo Giardino

The fine structure constant, alpha, is shown to be proportional to the ratio of the quanta of electric and magnetic flux of force of the electron, and provides a new representation, which is global across all unit systems. Consequently, a…

High Energy Physics - Phenomenology · Physics 2023-03-14 Michael Edmund Tobar

We forecast the ability of future CMB and galaxy lensing surveys to constrain variations of the fine structure constant. We found that lensing data, as those expected from satellite experiments as Euclid could improve the constraint from…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Matteo Martinelli , Eloisa Menegoni , Alessandro Melchiorri

We demonstrate that recent measurements of Cosmic Microwave Background temperature and polarization anisotropy made by the ACBAR, QUAD and BICEP experiments substantially improve the cosmological constraints on possible variations of the…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-28 Eloisa Menegoni , Silvia Galli , James Bartlett , Carlos J. A. P. Martins , Alessandro Melchiorri

We report a robust constrain on the possible variation of fine-structure constant, alpha = e^2/(hbar*c), obtained using O III 4959,5007, nebular emission lines from QSOs. We find Delta-alpha/alpha=-(2.1 +/- 1.6) x 10^(-5) based on a well…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 H. Rahmani , N. Maheshwari , R. Srianand

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

[O III]$\lambda\lambda$4960,5008 doublet are often the strongest narrow emission lines in starburst galaxies and quasi-stellar objects (QSOs), and thus are a promising probe to possible variation of the fine-structure constant $\alpha$ over…

Astrophysics of Galaxies · Physics 2023-10-30 Ge Li , Luming Sun , Xiangjun Chen , Hongyan Zhou

We consider the signatures of a domain wall produced in the spontaneous symmetry breaking involving a dilaton-like scalar field coupled to electromagnetism. Domains on either side of the wall exhibit slight differences in their respective…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-18 Keith A. Olive , Marco Peloso , Jean-Philippe Uzan
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