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In this paper, we present the details of the ab initio high-precision configuration interaction and many-body perturbation theory calculations that were used in a previous work to place limits on the dependence of the fine-structure…

Atomic Physics · Physics 2013-12-06 A. Ong , J. C. Berengut , V. V. Flambaum

The gravitational potential phi = GM/Rc^2 at the surface of the white dwarf G191-B2B is 10,000 times stronger than that at the Earth's surface. Numerous photospheric absorption features are detected, making this a suitable environment to…

Hot white dwarf stars are the ideal probe for a relationship between the fine-structure constant and strong gravitational fields, providing us with an opportunity for a direct observational test. We study a sample of hot white dwarf stars,…

Recently, white dwarf stars have found a new use in the fundamental physics community. Many prospective theories of the fundamental interactions of Nature allow traditional constants, like the fine structure constant $\alpha$, to vary in…

Solar and Stellar Astrophysics · Physics 2014-10-14 S. P. Preval , M. A. Barstow , J. B. Holberg , J. D. Barrow , J. C. Berengut , J. K. Webb , D. Dougan , J. Hu

In this paper, we investigate how the fine structure constant, $\alpha$, locally varies in the presence of a static and spherically symmetric gravitational source. The procedure consists in calculating the solution and the energy…

General Relativity and Quantum Cosmology · Physics 2016-09-27 V. B. Bezerra , M. S. Cunha , C. R. Muniz , M. O. Tahim , H. S. Vieira

The fine structure constant, $\alpha$, sets the strength of the electromagnetic force. The Standard Model of particle physics provides no explanation for its value, which could potentially vary. The wavelengths of stellar absorption lines…

Solar and Stellar Astrophysics · Physics 2022-11-30 Michael T. Murphy , Daniel A. Berke , Fan Liu , Chris Flynn , Christian Lehmann , Vladimir A. Dzuba , Victor V. Flambaum

In extensions of general relativity and in theories aiming at unifying gravity with the forces of the Standard Model, the value of the "fundamental constants" is often determined by the vacuum expectation value of new fields, which may thus…

General Relativity and Quantum Cosmology · Physics 2014-03-19 Cosimo Bambi

White dwarf atmospheres are subjected to gravitational potentials around $10^5$ times larger than occur on Earth. They provide a unique environment in which to search for any possible variation in fundamental physics in the presence of…

A method offering an order of magnitude sensitivity gain is described for using quasar spectra to investigate possible time or space variation in the fine structure constant, alpha. Applying the technique to a sample of 30 absorption…

We report a robust constrain on the possible variation of fine-structure constant, alpha = e^2/(hbar*c), obtained using O III 4959,5007, nebular emission lines from QSOs. We find Delta-alpha/alpha=-(2.1 +/- 1.6) x 10^(-5) based on a well…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 H. Rahmani , N. Maheshwari , R. Srianand

Star-forming galaxies at high redshifts are the ideal targets to probe the hypothetical variation of the fine-structure constant alpha over cosmological time scales. We propose a modification of the alkali doublets method which allows us to…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-10 S. A. Levshakov , M. G. Kozlov

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

A new method based on large-scale structure observations is proposed to probe a possible time variation of the fine-structure constant ($\alpha$). Our analyses are based on time-delay of Strong Gravitational Lensing and Type Ia Supernovae…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-09 L. R. Colaço , J. E. Gonzalez , R. F. L. Holanda

Spectra of molecular hydrogen (H$_2$) are employed to search for a possible proton-to-electron mass ratio ($\mu$) dependence on gravity. The Lyman transitions of H$_2$, observed with the Hubble Space Telescope towards white dwarf stars that…

General Relativity and Quantum Cosmology · Physics 2014-10-02 Julija Bagdonaite , Edcel J. Salumbides , Simon P. Preval , Martin A. Barstow , John D. Barrow , Michael T. Murphy , Wim Ubachs

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

The constraints on the time variation of the fine structure constant at recombination epoch relative to its present value, $\Delta\alpha/\alpha \equiv (\alpha_{\mathrm{rec}} - \alpha_{\mathrm{now}})/\alpha_{\mathrm{now}}$, are obtained from…

Astrophysics · Physics 2014-11-18 Masahiro Nakashima , Ryo Nagata , Jun'ichi Yokoyama

Astrophysical tests of the stability of fundamental couplings, such as the fine-structure constant $\alpha$, are a powerful probe of new physics. Recently these measurements, combined with local atomic clock tests and Type Ia supernova and…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-13 C. J. A. P. Martins , A. M. M. Pinho , P. Carreira , A. Gusart , J. López , C. I. S. A. Rocha

Calculation of the Dirac hydrogen atom spectrum in the framework of dynamical fine structure constant (alpha) variability discloses a small departure in the laboratory from Sommerfeld's formula for the fine structure shifts, possibly…

Astrophysics · Physics 2007-05-23 Jacob D. Bekenstein

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

Searches for variations of fundamental constants require accurate measurement errors. There are several potential sources of errors and quantifying each one accurately is essential. This paper addresses one source of uncertainty relating to…

Instrumentation and Methods for Astrophysics · Physics 2022-12-02 Chung-Chi Lee , John K. Webb , Darren Dougan , Vladimir A. Dzuba , Victor V. Flambaum
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