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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

In a previous work, the meaning of the Planck constant $h = \left( e^2 / 2 \alpha \right) \sqrt{\mu_0 / \epsilon_0}$, accomplished by solving Maxwell's electrodynamics laws with specific electric $1 / \tau_C = 1 / R_q C_q$ and magnetic $1/…

General Physics · Physics 2023-03-02 Paulo Roberto Bueno

Within the context of mass-varying neutrinos, we construct a cosmological model that has a phase transition in the electromagnetic fine structure constant \alpha at a redshift of 0.5. The model accommodates hints of a time variable \alpha…

High Energy Physics - Phenomenology · Physics 2008-11-26 L. Anchordoqui , V. Barger , H. Goldberg , D. Marfatia

If there is an extra U(1) gauge symmetry broken at low energies, then it may be possible from the charges of the known quarks and leptons under this U(1) to make inferences about how much gauge unification occurs at high scales and about…

High Energy Physics - Phenomenology · Physics 2011-05-12 S. M. Barr , Almas Khan

We discuss experiments and observations aimed at testing the possible space-time variability of fundamental physical constants, predicted by the modern theory. Specifically, we consider two of the dimensionless physical parameters which are…

Atomic Physics · Physics 2007-05-23 D. A. Varshalovich , A. Y. Potekhin , A. V. Ivanchik

In the present paper we demonstrate the possibility of the [SUSY(5)]^3 SUSY unification at the energy scale $\mu_{GUT}\approx 10^{18.3} GeV$ with the value of GUT inverse finestructure constant $\alpha_{GUT}^{-1}\approx 34.4$, which is very…

High Energy Physics - Theory · Physics 2007-05-23 L. Laperashvili , D. A. Ryzhikh

One of the topical problems of contemporary physics is a possible variability of the fundamental constants. Here we consider possible variability of two dimensionless constants which are most important for calculation of atomic and…

Atomic Physics · Physics 2016-09-08 D. A. Varshalovich , A. Y. Potekhin , A. V. Ivanchik

Astrophysical tests of the stability of Nature's fundamental couplings are a key probe of the standard paradigms in fundamental physics and cosmology. In this report we discuss updated constraints on the stability of the fine-structure…

High Energy Physics - Phenomenology · Physics 2015-08-26 S. M. João , C. J. A. P. Martins , I. S. A. B. Mota , P. M. T. Vianez

Recent astrophysical observations of quasar absorption systems indicate that the fine structure constant $\alpha$ and the proton-electron mass ratio $\mu$ may have evolved through the history of the universe. Motivated by these…

Astrophysics · Physics 2008-11-26 Seokcheon Lee

We present an up-to-date analysis for a precise determination of the effective fine structure constant and discuss the prospects for future improvements. We advocate to use a determination monitored by the Adler function which allows us to…

High Energy Physics - Phenomenology · Physics 2008-11-07 F. Jegerlehner

We derive the covariant equations of motion for Maxwell field theory and electrodynamics in multiscale spacetimes with weighted Laplacian. An effective spacetime-dependent electric charge of geometric origin naturally emerges from the…

High Energy Physics - Theory · Physics 2014-01-16 Gianluca Calcagni , Joao Magueijo , David Rodríguez Fernández

Ratio of electron charge radius and Compton wavelength of electron is known to be equal to the dimensionless electromagnetic coupling constant $e^2 /\hbar c$. It is pointed out that the coupling constant has two alternative interpretations:…

General Physics · Physics 2011-04-19 S. C. Tiwari

Data from e+e- annihilation into hadrons collected by the JADE experiment at centre-of-mass energies between 14 GeV and 44 GeV were used to study the four-jet rate as a function of the Durham algorithm's resolution parameter y_cut. The…

High Energy Physics - Experiment · Physics 2007-05-23 J. Schieck , S. Kluth , S. Bethke , P. A. Movilla Fernandez , C. Pahl , the JADE Collaboration

There exist four pion nucleon coupling constants, $f_{\pi^0, pp}$, $-f_{\pi^0, nn}$, $f_{\pi^+, pn} /\sqrt{2}$ and $ f_{\pi^-, np} /\sqrt{2}$ which coincide when up and down quark masses are identical and the electron charge is zero. While…

Nuclear Theory · Physics 2016-09-21 E. Ruiz Arriola , J. E. Amaro , R. Navarro Perez

The prospects for a determination of the strong coupling constant $\alpha_s$ via scaling violations of fragmentation functions in deeply inelastic scattering are studied. The statistical error in the case of an integrated luminosity of $250…

High Energy Physics - Phenomenology · Physics 2016-09-06 Dirk Graudenz

We perform a dispersive analysis of the $\omega\pi$ electromagnetic transition form factor, using as input the discontinuity provided by unitarity below the $\omega\pi$ threshold and including for the first time experimental data on the…

High Energy Physics - Phenomenology · Physics 2015-05-21 I. Caprini

Our calculations have shown that the 5f_5/2-7s_1/2 23131 cm^{-1} transition from the ground state in the ion Th^{3+} is very sensitive to the temporal variation of the fine structure constant alpha (q=-75300 cm^{-1}). The line is very…

Atomic Physics · Physics 2010-04-29 V. V. Flambaum , S. G. Porsev

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 explore the possibility that the reported time variation of the fine structure constant $\alpha$ is due to a coupling between electromagnetism and gravitation. This may reconcile the claimed results on $\alpha$ with the upper limit from…

General Relativity and Quantum Cosmology · Physics 2011-05-23 J. P. Mbelek , M. Lachièze-Rey

We consider scaling of the entanglement entropy across a topological quantum phase transition in one dimension. The change of the topology manifests itself in a sub-leading term, which scales as $L^{-1/\alpha}$ with the size of the…

Statistical Mechanics · Physics 2017-02-08 Yuting Wang , Tobias Gulden , Alex Kamenev
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