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We forecast the ability of future CMB and galaxy lensing surveys to constrain variations of the fine structure constant. We found that lensing data, as those expected from satellite experiments as Euclid could improve the constraint from…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Matteo Martinelli , Eloisa Menegoni , Alessandro Melchiorri

Contemporary multidimensional cosmological theories predict different variations of fundamental physical constants in course of the cosmological evolution. On the basis of the QSO spectra analysis, we show that the fine-structure constant…

Astrophysics · Physics 2007-05-23 D. A. Varshalovich , A. Y. Potekhin , A. V. Ivanchik , V. E. Panchuk , K. M. Lanzetta

We investigate the temporal evolution of the redshift and the luminosity distance within the standard Friedmann-Roberston-Walker cosmological model. The redshift and luminosity distance of sources evolve with time and we show that they tend…

Astrophysics · Physics 2007-05-23 C. Barbachoux , G. Le Denmat

I briefly present some current theoretical motivations for time or space variations of the fundamental constants of nature and review current key observational results. I focus on the fine-structure constant, and particularly on…

Astrophysics · Physics 2007-05-23 C. J. A. P. Martins

We review the observational information on the constancy of the fine structure constant alpha. We find that small improvements on the measurement of ^{187}Re lifetime can provide significant progress in exploring the range of variability…

Astrophysics · Physics 2009-11-07 G. Fiorentini , B. Ricci

Verification of theoretical predictions of an oscillating behavior of the fine-structure constant alpha with cosmic time requires high precision Delta alpha/alpha measurements at individual redshifts, while in earlier studies the mean Delta…

Astrophysics · Physics 2009-11-11 S. A. Levshakov , M. Centurion , P. Molaro , S. D'Odorico , D. Reimers , R. Quast , M. Pollmann

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 observations show that the electromagnetic fine-structure constant, $\alpha_e$, may vary with space and time. In the framework of Finsler spacetime, we propose here an anisotropic cosmological model, in which both the spatial and…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-09 Xin Li , Hai-Nan Lin

Evidence from a large sample of quasar absorption-line spectra in damped Lyman-alpha systems has suggested a possible time variation of the fine structure constant alpha. The most statistically significant portion of this sample involves…

Astrophysics · Physics 2009-09-15 Timothy P. Ashenfelter , Grant J. Mathews , Keith A. Olive

We propose and investigate a class of dynamical dark energy models in which the cosmological constant evolves from negative values in the early Universe to a positive value at low redshifts. This framework includes a generalised ladder-step…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-20 Mariam Bouhmadi-López , Beñat Ibarra-Uriondo

We investigate the evolution of the faint-end slope of the luminosity function, $\alpha$, using semi-analytical modeling of galaxy formation. In agreement with observations, we find that the slope can be fitted well by $\alpha (z) =a+b z$,…

Astrophysics · Physics 2009-11-13 S. Khochfar , J. Silk , R. A. Windhorst , R. E. Ryan

Sensitivity of the frequencies of twenty two atomic transitions to the variation of the fine structure constant $\alpha$ is calculated. The findings are to be used in search for possible variation of $\alpha$ across our Galaxy using high…

Atomic Physics · Physics 2022-06-22 V. A. Dzuba , V. V. Flambaum , M. T. Murphy , D. A. Berke

Detecting or placing upper limits on spacetime variations of fundamental constants requires quantifying every potential source of uncertainty. We continue our previous study into the impact of continuum variations on measurements of the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-02 John K. Webb , Chung-Chi Lee , Dinko Milaković , Darren Dougan , Vladimir A. Dzuba , Victor V. Flambaum

We derive a redshift drift formula within the framework of varying speed of light (VSL) theory using the specific ansatz for the variability of $c(t) = c_0 a^n(t)$. We show that negative values of the parameter $n$, which correspond to…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-26 Adam Balcerzak , Mariusz P. Dabrowski

Astrophysical tests of the stability of fundamental couplings, such as the fine-structure constant $\alpha$, are becoming an increasingly powerful probe of new physics. Here we discuss how these measurements, combined with local atomic…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-09 C. J. A. P. Martins , A. M. M. Pinho , R. F. C. Alves , M. Pino , C. I. S. A. Rocha , M. von Wietersheim

In view of new experimental results that strongly suggest a non-zero cosmological constant, it becomes interesting to revisit the Friedman-Lemaitre model of evolution of a universe with cosmological constant and radiation pressure. In this…

Astrophysics · Physics 2007-05-23 Robert Coquereaux , Alex Grossmann

Cosmography is a model-independent phenomenological approach to observational cosmology, relying on Taylor series expansions of physical quantities as a function of the cosmological redshift or other analogous variables. A recent work…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-27 C. J. A. P. Martins

We constrain the evolution of the rest-frame far-infrared (FIR) luminosity function out to high redshift, by combining several pieces of complementary information provided by the deep Balloon-borne Large-Aperture Submillimeter Telescope…

An attempt is made for a new type of analysis of the time-variability of the fine-structure constant trying to fit the most recent result from the laboratory measurements, the Oklo constraint and the data from the QSO absorption lines all…

Astrophysics · Physics 2009-12-04 Yasunori Fujii

The data from the QSO absorption lines indicating a nonzero time-variability of the fine-structure constant has been re-analyzed on the basis of a "damped-oscillator" fit, as motivated by the same type of behavior of a scalar field,…

Astrophysics · Physics 2015-06-24 Yasunori Fujii
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