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The possible variation of the electromagnetic fine structure constant $\alpha_e$ on cosmological scales arouses great interests in recent years. The strongly lensed gravitational waves and the electromagnetic counterparts could be used to…

General Relativity and Quantum Cosmology · Physics 2018-09-05 Xin Li , Li Tang , Hai-Nan Lin , Li-Li Wang

We study atomic systems that are in the frequency range of optical atomic clocks and have enhanced sensitivity to potential time-variation of the fine structure constant, alpha. The high sensitivity is due to coherent contributions from…

Atomic Physics · Physics 2010-09-16 J. C. Berengut , V. A. Dzuba , V. V. Flambaum

It has been a notably elusive task to find a remotely sensical ansatz for a calculation of Sommerfeld's electrodynamic fine-structure constant alpha_QED ~ 1/137.036 based on first principles. However, this has not prevented a number of…

High Energy Physics - Phenomenology · Physics 2014-12-23 U. D. Jentschura , I. Nandori

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

If the recent observations suggesting a time variation of the fine structure constant are correct, they imply the existence of an ultra light scalar particle. This particle inevitably couples to nucleons through the \alpha-dependence of…

High Energy Physics - Phenomenology · Physics 2009-11-07 Gia Dvali , Matias Zaldarriaga

The finite nuclear-size effect on the leading bound-electron g factor and the one-loop QED corrections to the bound-electron g factor is investigated for the ground state of hydrogen-like ions. The calculation is performed to all orders in…

Atomic Physics · Physics 2015-06-17 V. A. Yerokhin , C. H. Keitel , Z. Harman

Measurements of the fine-structure constant alpha require methods from across subfields and are thus powerful tests of the consistency of theory and experiment in physics. Using the recoil frequency of cesium-133 atoms in a matter-wave…

Atomic Physics · Physics 2018-12-14 Richard H. Parker , Chenghui Yu , Weicheng Zhong , Brian Estey , Holger Müller

There is a growing interest in astrophysical tests of the stability of dimensionless fundamental couplings, such as the fine-structure constant $\alpha$, as an optimal probe of new physics. The imminent arrival of the ESPRESSO spectrograph…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-25 C. S. Alves , A. C. O. Leite , C. J. A. P. Martins , T. A. Silva , S. A. Berge , B. S. A. Silva

Comparisons between the redshifts of spectral lines from cosmologically-distant galaxies can be used to probe temporal changes in low-energy fundamental constants like the fine structure constant and the proton-electron mass ratio. In this…

Astrophysics · Physics 2010-10-27 Nissim Kanekar

We investigate the variation of the fine-structure constant, {\alpha}, in symmetron models using N-body simulations in which the full spatial distribution of {\alpha} at different redshifts has been calculated. In particular, we obtain…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-29 Marvin F. Silva , Hans A. Winther , David F. Mota , C. J. A. P. Martins

We present a theoretical calculation on the time-variability of the fine-structure constant to fit the result of the recent precise analysis of the measurement of the QSO absorption lines. We find the parameters and initial values of the…

Astrophysics · Physics 2008-11-26 Yasunori Fujii

We study a theory in which the electromagnetic field is disformally coupled to a scalar field, in addition to a usual non-minimal electromagnetic coupling. We show that disformal couplings modify the expression for the fine-structure…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-16 Carsten van de Bruck , Jurgen Mifsud , Nelson J. Nunes

We study the change of the effective fine structure constant in the cosmological models of a scalar field with a non-vanishing coupling to the electromagnetic field. Combining cosmological data and terrestrial observations we place…

High Energy Physics - Phenomenology · Physics 2009-11-10 E. J. Copeland , N. J. Nunes , M. Pospelov

We present a theoretical justification for a method of extracting of supplementary information for the phase retrieval procedure taken from diffraction of fs-pulses from X-ray Free Electron Laser facilities. The approach is based on…

Materials Science · Physics 2015-02-18 A. Leonov , D. Ksenzov , A. Benediktovitch , I. Feranchuk , U. Pietsch

The hyperfine structure (hfs) and the g factor of a bound electron are caused by external magnetic fields. For the hfs, the magnetic field is due to the nuclear spin. A uniform-in-space and constant-in-time magnetic field is used to probe…

Atomic Physics · Physics 2015-05-14 Vladimir A. Yerokhin , Ulrich D. Jentschura

We consider the effect of the coupled variations of fundamental constants on the nucleon magnetic moment. The nucleon g-factor enters into the interpretation of the measurements of variations in the fine-structure constant, alpha, in both…

High Energy Physics - Phenomenology · Physics 2011-12-19 Feng Luo , Keith A. Olive , Jean-Philippe Uzan

The present review includes the description of theoretical methods for the investigations of the spectra of hydrogen-like systems. Various versions of the quasipotential approach and the method of the effective Dirac equation are…

High Energy Physics - Phenomenology · Physics 2011-07-19 Valeri V. Dvoeglazov , Rudolf N. Faustov , Yuri N. Tyukhtyaev

We study the dependence of the primordial nuclear abundances as a function of the electromagnetic fine-structure constant $\alpha$, keeping all other fundamental constants fixed. We update the leading nuclear reaction rates, in particular…

High Energy Physics - Theory · Physics 2023-05-26 Ulf-G. Meißner , Bernard Ch. Metsch , Helen Meyer

Fe II emission lines are observed from nearly all classes of astronomical objects over a wide spectral range from the infrared to the ultraviolet. To meaningfully interpret these lines, reliable atomic data are necessary. In work presented…

Atomic Physics · Physics 2019-03-12 Yier Wan , C. Favreau , S. D. Loch , B. M. McLaughlin , Yueying Qi , P. C. Stancil

We perform accurate calculations of the dependence of transition frequencies in two valence electron atoms and ions on a variation of the fine structure constant, alpha. The relativistic Hartree-Fock method is used with many-body…

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