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We search for transient variations of the fine structure constant using data from a European network of fiber-linked optical atomic clocks. By searching for coherent variations in the recorded clock frequency comparisons across the network,…

We perform a likelihood analysis of the recently released BOOMERanG and MAXIMA data, allowing for the possibility of a time-varying fine-structure constant. We find that in general this data prefers a value of $\alpha$ that was smaller in…

Astrophysics · Physics 2008-11-26 P. P. Avelino , C. J. A. P. Martins , G. Rocha , P. Viana

We report on the spectroscopy of radio-frequency transitions between nearly-degenerate, opposite-parity excited states in atomic dysprosium (Dy). Theoretical calculations predict that these states are very sensitive to variation of the…

Atomic Physics · Physics 2013-08-14 N. Leefer , C. T. M. Weber , A. Cingöz , J. R. Torgerson , D. Budker

Development of fundamental physics relies on the constancy of various fundamental quantities such as the fine structure constant. Detecting or constraining the possible time variations of these fundamental physical quantities is an…

Astrophysics · Physics 2009-11-10 H. Chand , R. Srianand , P. Petitjean , B. Aracil

We present a detailed analysis (including redshift tomography) of the cosmic dipoles in the Keck+VLT quasar absorber and in the Union2 SnIa samples. We show that the fine structure constant cosmic dipole obtained through the Keck+VLT quasar…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Antonio Mariano , Leandros Perivolaropoulos

Sensitivity coefficients to temporal variation of the fine-structure constant alpha for transitions between the fine-structure (FS) sub-levels of the ground states of C I, Si I, S I, Ti I, Fe I, N II, Fe II, O III, S III, Ar III, Fe III, Mg…

Astrophysics · Physics 2009-09-01 M. G. Kozlov , S. G. Porsev , S. A. Levshakov , D. Reimers , P. Molaro

Theories unifying gravity with other interactions suggest spatial and temporal variation of fundamental ``constants'' in the Universe. A change in the fine structure constant, alpha, could be detected via shifts in the frequencies of atomic…

We extend our recent work on the effects of a time-varying fine-structure constant $\alpha$ in the cosmic microwave background, by providing a thorough analysis of the degeneracies between $\alpha$ and the other cosmological parameters, and…

Testing the spatial variation of fine-structure constant $\alpha$ indicated in [Webb et al., Phys. Rev. Lett. 107, 191101 (2011)] with terrestrial laboratory atomic measurements requires at least $\dot{\alpha}/\alpha \sim…

Atomic Physics · Physics 2016-01-20 V. A. Dzuba , M. S. Safronova , U. I. Safronova , V. V. Flambaum

We present a detailed analysis of present and future Cosmic Microwave Background constraints of the value of the fine-structure constant, $\alpha$. We carry out a more detailed analysis of the WMAP first-year data, deriving state-of-the-art…

Numerous few-electron atomic systems are considered which can be used effectively for observing a potential variation of the fine-structure constant $\alpha$ and the electron-proton mass ratio $m_e/m_p$. We examine optical magnetic dipole…

In the present report the author presents a simple and systematically defined formula for the fine structure constant based only on the number $\pi$. The difference between the suggested value and the currently known experimental one is…

General Physics · Physics 2007-05-23 Anastass Anastasov

(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

This paper is devoted to the study of a discrepancy-type characteristic -- the fixed volume discrepancy -- of the Fibonacci point set in the unit square. It was observed recently that this new characteristic allows us to obtain optimal rate…

Numerical Analysis · Mathematics 2019-08-14 Vladimir Temlyakov , Mario Ullrich

We reconsider the Re187 bound on the variation of the fine-structure constant. We combine the meteoritic measurement with several present-day lab measurements to firmly establish the quantitative upper limit to the time variation over the…

We discuss how existing astrophysical measurements of various combinations of the fine-structure constant $\alpha$, the proton-to-electron mass ratio $\mu$ and the proton gyromagnetic ratio g$_{p}$ towards the radio source PKS1413+135 can…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-01 A. M. R. V. L. Monteiro , M. C. Ferreira , M. D. Julião , C. J. A. P. Martins

The Delta-variance analysis, has proven to be an efficient and accurate method of characterising the power spectrum of interstellar turbulence. The implementation presently in use, however, has several shortcomings. We propose and test an…

Astrophysics · Physics 2009-11-13 V. Ossenkopf , M. Krips , J. Stutzki

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

Recent cosmological tensions pose difficulties for $\Lambda$CDM. Forthcoming facilities will be able to check whether these tensions result from systematic effects or indeed with the $\Lambda$CDM model itself. However, these new data will…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-12 Dinko Milaković , John K. Webb

We propose a new method to probe for variations in the fine structure constant alpha using clusters of galaxies, opening up a window on a new redshift range for such constraints. Hot clusters shine in the X-ray mainly due to bremsstrahlung,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Silvia Galli