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Related papers: Constraints on variation in $\alpha$ and $m_e$ fro…

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We have shown that the varying physical constant model is consistent with the recently published variational approach wherein Einstein equations are modified to include the variation of the speed of light c, gravitational constant G and…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-21 Rajendra P. Gupta

We reconsider several current bounds on the variation of the fine-structure constant in models where all gauge and Yukawa couplings vary in an interdependent manner, as would be expected in unified theories. In particular, we re-examine the…

High Energy Physics - Phenomenology · Physics 2009-09-15 Keith A. Olive , Maxim Pospelov , Yong-Zhong Qian , Alain Coc , Michel Casse , Elisabeth Vangioni-Flam

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

We use recent astrophysical and local tests of the stability of the fine-structure constant, $\alpha$, to constrain a particular phenomenological but physically motivated class of models in which the dark energy equation of state can…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-12 C. J. A. P. Martins , M. Prat Colomer

Many physical theories beyond the Standard Model predict time variations of basic physics parameters. Direct measurement of the time variations of these parameters is very difficult or impossible to achieve. By contrast, measurements of…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-29 Rodger I. Thompson

Varying fundamental constants (VFC) [e.g., the fine-structure constant, $\alpha_{\rm EM}$] can arise in numerous extended cosmologies. Through their effect on the decoupling of baryons and photons during last scattering and reionisation,…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-13 Luke Hart , Jens Chluba

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

We relate possible cosmological variations in the mass ratio mu \equiv m_p/m_e and the fine structure constant alpha to long-range composition-dependent forces mediated by a scalar field. The differential acceleration eta in Eotvos-type…

High Energy Physics - Phenomenology · Physics 2010-10-27 Thomas Dent

The six parameters of the standard $\Lambda$CDM model have best-fit values derived from the Planck temperature power spectrum that are shifted somewhat from the best-fit values derived from WMAP data. These shifts are driven by features in…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-22 Planck Collaboration , N. Aghanim , Y. Akrami , M. Ashdown , J. Aumont , M. Ballardini , A. J. Banday , R. B. Barreiro , N. Bartolo , S. Basak , K. Benabed , M. Bersanelli , P. Bielewicz , A. Bonaldi , L. Bonavera , J. R. Bond , J. Borrill , F. R. Bouchet , C. Burigana , E. Calabrese , J. -F. Cardoso , A. Challinor , H. C. Chiang , L. P. L. Colombo , C. Combet , B. P. Crill , A. Curto , F. Cuttaia , P. de Bernardis , A. de Rosa , G. de Zotti , J. Delabrouille , E. Di Valentino , C. Dickinson , J. M. Diego , O. Doré , A. Ducout , X. Dupac , S. Dusini , G. Efstathiou , F. Elsner , T. A. Enßlin , H. K. Eriksen , Y. Fantaye , F. Finelli , F. Forastieri , M. Frailis , E. Franceschi , A. Frolov , S. Galeotta , S. Galli , K. Ganga , R. T. Génova-Santos , M. Gerbino , J. González-Nuevo , K. M. Górski , A. Gruppuso , J. E. Gudmundsson , D. Herranz , E. Hivon , Z. Huang , A. H. Jaffe , W. C. Jones , E. Keihänen , R. Keskitalo , K. Kiiveri , J. Kim , T. S. Kisner , L. Knox , N. Krachmalnicoff , M. Kunz , H. Kurki-Suonio , G. Lagache , J. -M. Lamarre , A. Lasenby , M. Lattanzi , C. R. Lawrence , M. Le Jeune , F. Levrier , A. Lewis , P. B. Lilje , M. Lilley , V. Lindholm , M. López-Caniego , P. M. Lubin , Y. -Z. Ma , J. F. Macías-Pérez , G. Maggio , D. Maino , N. Mandolesi , A. Mangilli , M. Maris , P. G. Martin , E. Martínez-González , S. Matarrese , N. Mauri , J. D. McEwen , P. R. Meinhold , A. Mennella , M. Migliaccio , M. Millea , M. -A. Miville-Deschênes , D. Molinari , A. Moneti , L. Montier , G. Morgante , A. Moss , A. Narimani , P. Natoli , C. A. Oxborrow , L. Pagano , D. Paoletti , G. Patanchon , L. Patrizii , V. Pettorino , F. Piacentini , L. Polastri , G. Polenta , J. -L. Puget , J. P. Rachen , B. Racine , M. Reinecke , M. Remazeilles , A. Renzi , M. Rossetti , G. Roudier , J. A. Rubiño-Martín , B. Ruiz-Granados , L. Salvati , M. Sandri , M. Savelainen , D. Scott , C. Sirignano , G. Sirri , L. Stanco , A. -S. Suur-Uski , J. A. Tauber , D. Tavagnacco , M. Tenti , L. Toffolatti , M. Tomasi , M. Tristram , T. Trombetti , J. Valiviita , F. Van Tent , P. Vielva , F. Villa , N. Vittorio , B. D. Wandelt , I. K. Wehus , M. White , A. Zacchei , A. Zonca

We use the Cosmic Microwave Background Anisotropies (CMBA) power spectra to constrain the cosmological variation of gravitational constant G. It is found that the sensitivity of CMBA to the variation of G is enhanced when G is required to…

Astrophysics · Physics 2008-11-26 K. C. Chan , M. -C. Chu

Cosmological variation of the fine structure constant $\alpha$ due to the evolution of a spatially homogeneous ultra-light scalar field ($m \sim H_0$) during the matter and $\Lambda$ dominated eras is analyzed. Agreement of $\Delta…

Astrophysics · Physics 2009-11-07 Carl L. Gardner

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…

Astrophysics · Physics 2007-12-31 Paolo Molaro

A combined analysis of Cosmic Microwave Background (CMB) and Lyman-a forest data allows to constrain the matter power spectrum from small scales of about 1 Mpc/h all the way to the horizon scale. The long lever arm and complementarity…

Astrophysics · Physics 2009-10-08 Matteo Viel , Martin G. Haehnelt , Antony Lewis

Recent experimental data indicates that the fine structure constant alpha may be varying on cosmological time scales. We consider the possibility that such a variation could be induced by a second order phase transition which occurs at late…

High Energy Physics - Phenomenology · Physics 2010-04-05 Z. Chacko , C. Grojean , M. Perelstein

(Abridged) Many-multiplet (MM) method applied to three inhomogeneous samples of Keck/HIRES quasar absorption spectra gives a shift in the value of the fine-structure constant of Delta alpha/alpha = (-5.4+/-1.2) 10^{-6} in the redshift range…

Astrophysics · Physics 2017-08-23 Sergei A. Levshakov

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

We present observational constraints on a scalar-tensor gravity theory by $\chi^2$ test for CMB anisotropy spectrum. We compare the WMAP temperature power spectrum with the harmonic attractor model, in which the scalar field has its…

Astrophysics · Physics 2009-11-10 Ryo Nagata , Takeshi Chiba , Naoshi Sugiyama

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

We perform a comparison of WMAP 9-year (WMAP9) and Planck 2015 cosmic microwave background (CMB) temperature power spectra across multipoles $30\leq\ell\leq1200$. We generate simulations to estimate the correlation between the two datasets…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-01 Yajing Huang , Graeme E. Addison , Janet L. Weiland , Charles L. Bennett

We critically assess recent claims suggesting that upper limits on the time variation of the fine-structure constant tightly constrain the coupling of a dark energy scalar field to the electromagnetic sector, and, indirectly, the violation…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-20 P. P. Avelino
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