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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 fundamental constants at recombination can differ from their present-day values due to degeneracies in cosmological parameters, raising the possibility of yet-undiscovered physics coupled directly to the Standard Model. We study the…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-20 Masha Baryakhtar , Olivier Simon , Zachary J. Weiner

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

Optical quasar spectra can be used to trace variations of the fine-structure constant alpha. Controversial results that have been published in last years suggest that in addition to to wavelength calibration problems systematic errors might…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Nils Prause , Dieter Reimers

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

A phenomenological model is proposed to explain the recent observed cosmological variation of the fine structure constant as an effect of the quantum vacuum, assuming a flat universe with cosmological constant $\Lambda$ in the cases…

Astrophysics · Physics 2010-12-17 Antonio F. Rañada

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

We report the detection of the satellite 18 cm OH lines at 1612 and 1720 MHz in the z=0.2467 molecular absorption system toward the radio source PKS 1413+135. The two OH lines are conjugate; the 1612 MHz line is seen in absorption while the…

Astrophysics · Physics 2009-11-10 Jeremy Darling

Exploring the possibility that fundamental constants of Nature might vary temporally or spatially constitutes one of the key science drivers for the European Southern Observatory's ESPRESSO spectrograph on the VLT and for the HIRES…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 Chung-Chi Lee , John K. Webb , R. F. Carswell , Dinko Milaković

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

Cosmological dark energy is a natural source of variation of the fine structure constant. Using a model-independent approach we show that once general assumptions about the alpha-varying interactions are made, astronomical probes of its…

Astrophysics · Physics 2015-06-24 David Parkinson , Bruce A. Bassett , John D. Barrow

Astrophysical tests of the stability of fundamental couplings are becoming an increasingly important probe of new physics. Motivated by the recent availability of new and stronger constraints we update previous works testing the consistency…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-31 C. J. A. P. Martins , A. M. M. Pinho

High resolution spectra of quasar absorption systems provide the best constraints on temporal or spatial changes of fundamental constants in the early universe. An important systematic that has never before been quantified concerns model…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-25 Chung-Chi Lee , John K. Webb , Dinko Milaković , Robert F. Carswell

The present constraints on fundamental constant variation (\alpha and \mu) obtained in the radio range are reviewed, coming essentially from absorption lines in front of quasars of intermediate to high-z galaxies, through CO, HI, OH, HCO+,…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-06 F. Combes

Exploring physics beyond General Relativity and the Standard Model of Particle Physics involves investigating spacetime variations in natural constants. This study employs an $H_2$-single of QSO 0347-383 observational spectrum to propose a…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-09 T. D. Le

We statistically analyse a recent sample of data points measuring the fine-structure constant alpha (relative to the terrestrial value) in quasar absorption systems. Using different statistical techniques, we find general agreement with…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-02 J. C. Berengut , E. M. Kava , V. V. Flambaum

We explore a possible time variation of the fine structure constant ($\alpha \equiv e^2/\hbar c$) using the Sunyaev-Zel'dovich effect measurements of galaxy clusters along with their X-ray observations. Specifically, the ratio of the…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-24 Zhi-E Liu , Wen-Fei Liu , Tong-Jie Zhang , Zhong-Xu Zhai , Kamal Bora

It was hypothesized in the literature that some physical parameters may be time-evolving and the astrophysical data can serve as a probe. Recently, James Webb Space Telescope (JWST) have released its early observations. In this work, we…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-15 Ze-Fan Wang , Lei Lei , Lei Feng , Yi-Zhong Fan

We use the Cosmic Microwave Background (CMB) anisotropy data from Planck to constrain the spatial fluctuations of the fine-structure constant \alpha. Through Thompson scattering of CMB photons, spatial anisotropies of \alpha lead to…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-07 Jon O'Bryan , Joseph Smidt , Francesco De Bernardis , Asantha Cooray

Quasar spectra reveal a rich array of important astrophysical information about galaxies which intersect the quasar line of sight. They also enable tests of the variability of fundamental constants over cosmological time and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Michael T. Murphy , Julian C. Berengut