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Related papers: Revised fits to $\Delta\alpha/\alpha$ in consisten…

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Theories unifying gravity and other interactions suggest the possibility of spatial and temporal variation of physical ``constants''. Accuracy achieved for the atomic optical frequency standards (optical clocks) approaches the level when…

Atomic Physics · Physics 2009-02-05 V. A. Dzuba , V. V. Flambaum.

We make use of Dirac LNH and results for a time varying fine structure constant in order to derive possible laws of variation for speed of light, the number of nucleons in the Universe, energy density and gravitational constant. By…

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

If the fine structure constant $\alpha =e^2/(\hbar c)$ were to change, then a number of interpretations would be possible, attributing this change either to variations in the electron charge, the dielectric constant of the vacuum, the speed…

Astrophysics · Physics 2009-10-31 John D. Barrow , Joao Magueijo

(Abridged) Many-multiplet (MM) method applied to three inhomogeneous samples of Keck/HIRES quasar absorption spectra gives a shift in the value of the fine-structure constant of Delta alpha/alpha = (-5.4+/-1.2) 10^{-6} in the redshift range…

Astrophysics · Physics 2017-08-23 Sergei A. Levshakov

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

From astrophysics there are indications that the finestructure constant $\alpha $ has changed during the past 10 billion years. Within grand unification one can deduce that also the QCD scale has changed. Tests for a time variation of this…

High Energy Physics - Phenomenology · Physics 2007-05-23 Harald Fritzsch

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 study the cosmological constraints of the time variation of the electron mass $m_e$ and the fine-structure constant $\alpha$, using data of cosmic microwave background, supernovae light curve and baryon acoustic oscillation (BAO) data…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-15 Yo Toda , Osamu Seto

We derive formulae for the time variation of the gravitational ``constant'' and of the fine structure ``constant'' in various models with extra dimensions and analyze their consistency with the observational data.

General Relativity and Quantum Cosmology · Physics 2007-05-23 E. Garcia-Berro , Yu. A. Kubyshin , P. Loren-Aguilar

Electromagnetic and gravitational central-field problems are studied with relativistic quantum mechanics on curved space-time backgrounds. Corrections to the transition current are identified. Analogies of the gravitational and…

General Physics · Physics 2015-02-04 U. D. Jentschura , J. H. Noble , I. Nandori

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

We presented a new physical model that links the maximum speed of light with the minimal Planck scale into a maximal-acceleration Relativity principle in the spacetime tangent bundle and in phase spaces (cotangent bundle). The maximal…

High Energy Physics - Theory · Physics 2009-11-07 Carlos Castro

Attempts to measure the variability of the fine structure constant alpha over cosmological time, using spectra of high redshift quasars have produced conflicting results. We use the Many Multiplet (MM) method with Mg II and Fe II lines on…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 A. Songaila , L. L. Cowie

Tests of the stability of nature's fundamental constants are one of the cornerstones of the ongoing search for the new physics which is required to explain the recent acceleration of the universe. The two main settings for these tests are…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-18 C. J. A. P. Martins , M. Vila Miñana

The time variation of fundamental mass scales can have profound cosmological implications. We investigate a particular model of crossover quintessence which is compatible with all present cosmological observations. This model can also…

High Energy Physics - Phenomenology · Physics 2017-08-23 C. Wetterich

We report a new constraint on the variation of the fine-structure constant based on the analysis of 15 Si IV doublets selected from a ESO-UVES sample. We find \Delta\alpha/\alpha = (+0.15+/-0.43) x 10^-5 over a redshift range of 1.59< z <…

Astrophysics · Physics 2009-11-10 Hum Chand , Patrick Petitjean , Raghunathan Srianand , Bastien Aracil

Detecting any evolution of dimensionless in the ratios of physical quantities, such as the fine structure constant, would prove that the Weak Equivalence Principle is violated and lead to a paradigm shift in physics. High resolution…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-03 Dinko Milaković

Quasar absorption spectral data indicate the presence of a spatial gradient in the electromagnetic fine-structure constant $\alpha$ on cosmological length scales. We point out that experiments with accelerometers, including torsion pendula…

Atomic Physics · Physics 2021-06-30 Yevgeny V. Stadnik

The accelerating universe is closely related to today's version of the cosmological constant problem; fine-tuning and coincidence problems. We show how successfully the scalar-tensor theory, a rather rigid theoretical idea, provides us with…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-01 Yasunori Fujii

In this paper, we formulate a generalization of the simple Bekenstein-Sandvik-Barrow-Magueijo (BSBM) theory of varying alpha by allowing the coupling constant, \omega, for the corresponding scalar field \psi\ to depend on \psi. We focus on…

General Relativity and Quantum Cosmology · Physics 2012-01-13 John D. Barrow , Sean Z. W. Lip