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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 study the $\Lambda(\alpha)$CDM models with $\Lambda(\alpha)$ being a function of the time-varying fine structure constant $\alpha$. We give a close look at the constraints on two specific $\Lambda(\alpha)$CDM models with one and two…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-13 Jin-Jun Zhang , Lu Yin , Chao-Qiang Geng

Last year I talked at this meeting about a possible time dependence of the QCD coupling constant $\alpha_s$. This year I shall look into the problem once more, without fully repeating the arguments given last year. Astrophysical indications…

High Energy Physics - Phenomenology · Physics 2009-11-10 Harald Fritzsch

Large statistical samples of quasar spectra have previously indicated possible cosmological variations in the fine-structure constant, $\alpha$. A smaller sample of higher signal-to-noise ratio spectra, with dedicated calibration, would…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 T. M. Evans , M. T. Murphy , J. B. Whitmore , T. Misawa , M. Centurion , S. D'Odorico , S. Lopez , C. J. A. P. Martins , P. Molaro , P. Petitjean , H. Rahmani , R. Srianand , M. Wendt

The ^{207}Pb^{19}F molecule possesses a pair of closely spaced levels of opposite parity due to near cancelation of the omega-type doubling and magnetic hyperfine interaction energy shifts [Alphei et al., Phys. Rev. A, 83, 040501 (2011)].…

Atomic Physics · Physics 2014-05-08 V. V. Flambaum , Y. V. Stadnik , M. G. Kozlov , A. N. Petrov

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

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

Peik and Tamm [Europhys. Lett. 61, 181 (2003)] proposed a nuclear clock based on the isomeric transition between the ground state and the first excited state of thorium-229. This transition was recognized as a potentially sensitive probe of…

Atomic Physics · Physics 2021-01-19 Pavel Fadeev , Julian C. Berengut , Victor V. Flambaum

Dynamical models of dark energy can imply that the fine structure constant $\alpha$ varies over cosmological time scales. Data on shifts in resonance energies $E_r$ from the Oklo natural fission reactor have been used to place restrictive…

Nuclear Theory · Physics 2015-10-13 Leila Hamdan , Edward D. Davis

I review recent constraints on and claimed detections of a time-varying fine-structure constant $\alpha$. Our results are consistent with no variation in $\alpha$ from the epoch of recombination to the present day, and restrict any such…

High Energy Physics - Phenomenology · Physics 2016-09-06 C. J. A. P. Martins

If the recent observations suggesting a time variation of the fine structure constant are correct, they imply the existence of an ultra light scalar particle. This particle inevitably couples to nucleons through the \alpha-dependence of…

High Energy Physics - Phenomenology · Physics 2009-11-07 Gia Dvali , Matias Zaldarriaga

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

Temporal and spatial variation of fine-structure constant $\alpha\equiv e^2/\hbar c$ in cosmology has been reported in analysis of combination Keck and VLT data. This paper studies this variation based on consideration of basic spacetime…

General Relativity and Quantum Cosmology · Physics 2015-09-02 Sze-Shiang Feng , Mu-Lin Yan

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…

Astrophysics · Physics 2009-10-31 Manoj Kaplinghat , Robert J. Scherrer , Michael S. Turner

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…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Eloisa Menegoni , Maria Archidiacono , Erminia Calabrese , Silvia Galli , C. J. A. P. Martins , Alessandro Melchiorri

Absorption-line systems detected in high resolution quasar spectra can be used to compare the value of dimensionless fundamental constants such as the fine-structure constant, alpha, and the proton-to-electron mass ratio, mu = m_p/m_e, as…

We argue that the accuracy by which the isochron parameters of the decay $^{187}{\rm Re}\to ^{187}{\rm Os}$ are determined by dating iron meteorites may not directly constrain the possible time-dependence of the decay rate and hence of the…

High Energy Physics - Phenomenology · Physics 2009-11-10 Yasunori Fujii , Akira Iwamoto

The relative effects of variation of the fine structure constant alpha=e^2/hc and dimensionless strong interaction parameter m_q/Lambda_{QCD} are enhanced 5-6 orders of magnitude in very narrow ultraviolet transition between the ground and…

Atomic Physics · Physics 2011-11-23 V. V. Flambaum

The strongest transitions of Zn and CrII are the most sensitive to relative variations in the fine-structure constant ($\Delta\alpha/\alpha$) among the transitions commonly observed in quasar absorption spectra. They also lie within just…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-04 Michael T. Murphy , Adrian L. Malec , J. Xavier Prochaska

We derive strong observational limits on any possible large-scale spatial variation in the values of physical 'constants' whose space-time evolution is driven by a scalar field. The limits are imposed by the isotropy of the microwave…

Astrophysics · Physics 2009-11-10 John D. Barrow
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