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相关论文: Time Variation of the Fine Structure Constant Driv…

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The brightest southern quasar above redshift $z=1$, HE 0515$-$4414, with its strong intervening metal absorption-line system at $z_{abs}=1.1508$, provides a unique opportunity to precisely measure or limit relative variations in the…

宇宙学与河外天体物理 · 物理学 2016-12-07 Srđan M. Kotuš , Michael T. Murphy , Robert F. Carswell

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…

宇宙学与河外天体物理 · 物理学 2024-10-02 John K. Webb , Chung-Chi Lee , Dinko Milaković , Darren Dougan , Vladimir A. Dzuba , Victor V. Flambaum

At redshifts z_abs < 2, quasar absorption-line constraints on space-time variations in the fine-structure constant, alpha, rely on the comparison of MgII and FeII transition wavelengths. One potentially important uncertainty is the relative…

天体物理学 · 物理学 2008-11-26 Y. Fenner , M. T. Murphy , B. K. Gibson

Current analyses of VLT/UVES quasar spectra disagree with the Keck/HIRES evidence for a varying fine-structure constant, alpha. To investigate this we introduce a simple method for calculating the minimum possible uncertainty on…

天体物理学 · 物理学 2015-06-24 M. T. Murphy , J. K. Webb , V. V. Flambaum

Any time variation in the fine-structure constant alters the ionization history of the universe and therefore changes the pattern of cosmic microwave background fluctuations. We calculate the changes in the spectrum of these fluctuations as…

天体物理学 · 物理学 2009-10-31 Manoj Kaplinghat , Robert J. Scherrer , Michael S. Turner

We have investigated some cosmological consequences of variation of the fine structure constant, $\alpha$, in the context of the Bekenstein-Sandvik-Barrow-Magueijo (BSBM) model. In this context, such a variation is attributed to electric…

广义相对论与量子宇宙学 · 物理学 2021-08-10 Yousef Bisabr

The possibility of variation of the fundamental constants of nature has been a long-standing question, with important consequences for fundamental physics and cosmology. In particular, it has been shown that variations in the fine-structure…

宇宙学与河外天体物理 · 物理学 2020-07-01 Rodrigo S. Gonçalves , Susana Landau , Jailson S. Alcaniz , Rodrigo F. L. Holanda

We discuss present and future cosmological constraints on variations of the fine structure constant $\alpha$ induced by an early dark energy component having the simplest allowed (linear) coupling to electromagnetism. We find that current…

宇宙学与河外天体物理 · 物理学 2011-08-08 Erminia Calabrese , Eloisa Menegoni , C. J. A. P. Martins , Alessandro Melchiorri , Graca Rocha

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…

天体物理学 · 物理学 2008-11-26 P. P. Avelino , C. J. A. P. Martins , G. Rocha , P. Viana

We present constraints on the spacetime variation of the fine-structure constant $\alpha$ at redshifts $2.5\le z<9.5$ using JWST emission-line galaxies. The galaxy sample consists of 621 high-quality spectra with strong and narrow [O III]…

宇宙学与河外天体物理 · 物理学 2025-01-22 Linhua Jiang , Shuqi Fu , Feige Wang , Sarah E. I. Bosman , Zheng Cai , Hyunsung D. Jun , Zhiwei Pan , Fengwu Sun , Jinyi Yang , Huanian Zhang

The recent measurements of the Cosmic Microwave Background anisotropies at arcminute angular scales performed by the ACT and SPT experiments are probing the damping regime of CMB fluctuations. The analysis of these datasets unexpectedly…

宇宙学与河外天体物理 · 物理学 2013-05-30 Eloisa Menegoni , Maria Archidiacono , Erminia Calabrese , Silvia Galli , C. J. A. P. Martins , Alessandro Melchiorri

We calculate the dependence of atomic transition frequencies on the fine structure constant, $\alpha = e^2/\hbar c$, for some ions of Ti, Mn, Na, C, and O. The results of these calculations will be used in the search for variation of alpha…

天体物理学 · 物理学 2007-05-23 J. C. Berengut , V. A. Dzuba , V. V. Flambaum , M. V. Marchenko

There are obvious discrepancies among various experimental constraints on the variation of the fine-structure constant, $\alpha$. We attempt to discuss the issue in the framework of de Sitter invariant Special Relativity (${\cal SR}_{c,R}$)…

天体物理学 · 物理学 2015-06-24 Shao-Xia Chen , Neng-Chao Xiao , Mu-Lin Yan

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…

广义相对论与量子宇宙学 · 物理学 2018-09-05 Xin Li , Li Tang , Hai-Nan Lin , Li-Li Wang

Only astronomical observations can effectively probe in space-time the variabil ity of the physical dimensionless constants such as the fine structure constant and proton-to-electron mass ratio, \mu, which are related to fund amental forces…

天体物理学 · 物理学 2007-12-31 Paolo Molaro

The comparison of different atomic transition frequencies over time can be used to determine the present value of the temporal derivative of the fine structure constant alpha in a model-independent way without assumptions on constancy or…

原子物理 · 物理学 2009-11-10 E. Peik , B. Lipphardt , H. Schnatz , T. Schneider , Chr. Tamm , S. G. Karshenboim

Astrophysical observations suggest that the fine structure constant (alpha) may (or may not) be evolving over the cosmological time scale. This raises a much debated question: is alpha variation due to the variation of the speed of light…

高能物理 - 唯象学 · 物理学 2007-05-23 A. Yu. Ignatiev , B. J. Carson

We reanalyze Oklo $^{149}$Sm data using realistic models of the natural nuclear reactors. Disagreements among recent Oklo determinations of the time evolution of $\alpha$, the electromagnetic fine structure constant, are shown to be due to…

核实验 · 物理学 2008-11-26 C. R. Gould , E. I. Sharapov , S. K. Lamoreaux

We discuss the fundamemtal constants in the Standard Model of particle physics, in particular possible changes of these constants on the cosmological time scale. The Grand Unification of the observed strong, electromagnetic and weak…

高能物理 - 唯象学 · 物理学 2016-10-25 Harald Fritzsch

We study inhomogeneous cosmological variations in the fine structure 'constant', $\alpha ,$ in Friedmann universes. Inhomogeneous motions of the scalar field driving changes in $\alpha $ display spatial oscillations that decrease in…

天体物理学 · 物理学 2009-11-07 J. D. Barrow , J. Magueijo , H. B. Sandvik