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Recently it has been suggested that an increase in the fine structure constant alpha with time would decrease the entropy of a Reissner-Nordstrom black hole, thereby violating the second law of thermodynamics. In this note we point out…

High Energy Physics - Theory · Physics 2009-11-07 Malcolm Fairbairn , Michel H. G. Tytgat

In the Letter [1] (also [2]) there is a claim that the generalised second law of thermodynamics (entropy increase) for black holes provides some limits on the rate of variation of the fundamental constants of nature (electric charge e,…

General Relativity and Quantum Cosmology · Physics 2009-02-27 V. V. Flambaum

New and rather controversial observations hint that the fine structure constant \alpha may have been smaller in the early universe, suggesting that some of the fundamental ``constants'' of physics may be dynamical. In a recent paper,…

High Energy Physics - Theory · Physics 2010-04-28 S. Carlip , S. Vaidya

Here it is shown that the variation in the fine structure constant measured by Webb et al. matches the theoretically derived value for the maximum variation in the electronic charge permitted by the Generalized Second Law of Thermodynamics…

Astrophysics · Physics 2007-05-23 Jane H MacGibbon

Speculation that the fine-structure constant $\alpha$ varies in spacetime has a long history. We derive, in 4-D general relativity and in isotropic coordinates, the solution for a charged spherical black hole according to the framework for…

General Relativity and Quantum Cosmology · Physics 2013-11-06 Jacob D. Bekenstein , Marcelo Schiffer

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

A recent paper [DDL] claims that the increase of the proton electric charge e leads to a (forbidden) decrease of black hole entropy, therefore, possible evidence for variation of $\alpha=e^2/\hbar c$ [alpha] must be interpreted as a…

Astrophysics · Physics 2007-05-23 V. V. Flambaum

Here we apply the Generalized Second Law of Thermodynamics and derive upper limits on the variation in the fundamental constants. The maximum variation in the electronic charge permitted for black holes accreting and emitting in the present…

Astrophysics · Physics 2008-11-26 Jane H MacGibbon

The theoretical maximum time variation in the electronic charge permitted by the Generalized Second Law of Thermodynamics applied to black holes radiating and accreting in the cosmic microwave background matches the measured cosmological…

General Relativity and Quantum Cosmology · Physics 2010-04-02 Jane H. MacGibbon

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

If the fine structure constant is not really constant, is this due to a variation of $e$, $\hbar$, or $c$? It is argued that the only reasonable conclusion is a variable speed of light.

Quantum Physics · Physics 2009-11-07 Asher Peres

Astrophysical observations suggest that the fine structure constant (alpha) may (or may not) be evolving over the cosmological time scale. This raises a much debated question: is alpha variation due to the variation of the speed of light…

High Energy Physics - Phenomenology · Physics 2007-05-23 A. Yu. Ignatiev , B. J. Carson

We briefly review the recent experimental results on possible variations of the fine structure constant $\alpha$ on the cosmological time scale and its position dependence. We outline the theoretical grounds for the assumption that $\alpha$…

General Relativity and Quantum Cosmology · Physics 2012-05-11 K. A. Bronnikov , S. A. Kononogov

Recent experimental data indicates that the fine structure constant alpha may be varying on cosmological time scales. We consider the possibility that such a variation could be induced by a second order phase transition which occurs at late…

High Energy Physics - Phenomenology · Physics 2010-04-05 Z. Chacko , C. Grojean , M. Perelstein

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

Determination of the fine structure constant alpha and search for its possible variation are considered. We focus on a role of the fine structure constant in modern physics and discuss precision tests of quantum electrodynamics. Different…

Atomic Physics · Physics 2015-06-26 Savely G. Karshenboim

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 discuss the Flambaum commentary [arXiv:0808.2518] on the application of the Generalized Second Law of Thermodynamics to derive limits on the variation of fundamental constants, for example the fine structure constant.

General Relativity and Quantum Cosmology · Physics 2009-02-27 Jane H MacGibbon

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

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
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