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We introduce a methodology to test models with spatial variations of the fine-structure constant $\alpha$, based on the calculation of the angular power spectrum of these measurements. This methodology enables comparisons of observations…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-24 A. M. M. Pinho , M. Martinelli , C. J. A. P. Martins

Recent updated results of quasar spectra suggested a 3.9$\sigma$ significance of spatial variation of the fine-structure constant. Theoretically, it is important to examine whether the fine-structure constant, as a fundamental constant in…

General Relativity and Quantum Cosmology · Physics 2020-11-17 Zhe Chang , Qing-Hua Zhu

The detection of a spatial variation of the fine-structure constant, alpha, based on study of quasar absorption systems has recently been reported. The physics that causes this alpha-variation should have other observable manifestations,…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-16 J. C. Berengut , V. V. Flambaum , J. A. King , S. J. Curran , J. K. Webb

We analyze the consistency of different astronomical data of the variation in the fine-structure constant obtained with KECK and VLT. We tested the consistency using the Student test and confidence intervals. We splited the data sets in to…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-27 Lucila Kraiselburd , Susana J. Landau , Claudio Simeone

Temporal and spatial variation of fine-structure constant $\alpha\equiv e^2/\hbar c$ in cosmology has been reported in analysis of combination Keck and VLT data. This paper studies this variation based on consideration of basic spacetime…

General Relativity and Quantum Cosmology · Physics 2015-09-02 Sze-Shiang Feng , Mu-Lin Yan

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

Recent work by Webb {\it et al.} has provided indications of spatial variations of the fine-structure constant, $\alpha$, at a level of a few parts per million. Using a dataset of 293 archival measurements, they further show that a dipole…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-16 A. M. M. Pinho , C. J. A. P. Martins

A method offering an order of magnitude sensitivity gain is described for using quasar spectra to investigate possible time or space variation in the fine structure constant, alpha. Applying the technique to a sample of 30 absorption…

Spatial and temporal variations in the electron-to-proton mass ratio, mu, and in the fine-structure constant, alpha, are predicted in non-Standard models aimed to explain the nature of dark energy. Among them the so-called chameleon-like…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-20 S. A. Levshakov , I. I. Agafonova , P. Molaro , D. Reimers

In this paper, we investigate how the fine structure constant, $\alpha$, locally varies in the presence of a static and spherically symmetric gravitational source. The procedure consists in calculating the solution and the energy…

General Relativity and Quantum Cosmology · Physics 2016-09-27 V. B. Bezerra , M. S. Cunha , C. R. Muniz , M. O. Tahim , H. S. Vieira

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

Calculation of the Dirac hydrogen atom spectrum in the framework of dynamical fine structure constant (alpha) variability discloses a small departure in the laboratory from Sommerfeld's formula for the fine structure shifts, possibly…

Astrophysics · Physics 2007-05-23 Jacob D. Bekenstein

Murphy et al. (2003a, MNRAS, 345, 609) claim to find evidence of cosmological variations of the fine structure constant $\alpha$ in the spectra of intervening QSO absorption line systems. We find that this result is affected by systematic…

Astrophysics · Physics 2016-08-30 Rino Bandiera , Edvige Corbelli

The remarkable detection of a spatial variation in the fine-structure constant, alpha, from quasar absorption systems must be independently confirmed by complementary searches. In this letter, we discuss how terrestrial measurements of…

Atomic Physics · Physics 2012-09-11 J. C. Berengut , V. V. Flambaum

Astrophysical tests of the stability of dimensionless fundamental couplings, such as the fine-structure constant $\alpha$, are an area of much increased recent activity, following some indications of possible spacetime variations at the few…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-16 P. M. M. Leal , C. J. A. P. Martins , L. B. Ventura

Recent theoretical ideas and observational claims suggest that the fine structure constant alpha may be variable. We examine a spectrum of models in which alpha is a function of a scalar field. Specifically, we consider three scenarios:…

High Energy Physics - Phenomenology · Physics 2009-11-10 Charles L. Steinhardt

We review recent activity searching for variations in the fundamental constants of nature in quasar absorption spectra and in the laboratory. While research in this direction has been ongoing for many decades, the topic has recently been…

Atomic Physics · Physics 2011-02-02 J. C. Berengut , V. V. Flambaum

We have studied the Bekenstein-Sandvik-Barrow-Magueijo (BSBM) model for the spatial and temporal variations of the fine structure constant, alpha, with the aid of full N-body simulations which explicitly and self-consistently solve for the…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-04 Baojiu Li , David F. Mota , John D. Barrow

Star-forming galaxies at high redshifts are the ideal targets to probe the hypothetical variation of the fine-structure constant alpha over cosmological time scales. We propose a modification of the alkali doublets method which allows us to…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-10 S. A. Levshakov , M. G. Kozlov

The effect of fractal space time of the quantum particles on the variation of the fine structure constant $\alpha$ has been studied. The variation of fine structure constant has been investigated around De Broglie length $\lambda$ and…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-05 A. Bhattacharya , A. Chandra , B. Chakrabarti
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