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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

We study constraints on time variation of the fine structure constant alpha from cosmic microwave background (CMB) taking into account simultaneous change in alpha and the electron mass m_e which might be implied in unification theories. We…

Astrophysics · Physics 2008-11-26 Kazuhide Ichikawa , Toru Kanzaki , Masahiro Kawasaki

We studied the role of fundamental constants in an updated recombination scenario, focusing on the time variation of the fine structure constant \alpha and the electron mass m_e in the early Universe. Using CMB data including WMAP 5-yr…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-02 Claudia G. Scóccola , Susana J. Landau , Hector Vucetich

We investigate constraints on the time variation of the fine structure constant between the recombination epoch and the present epoch, \Delta\alpha/\alpha \equiv (\alpha_{rec} - \alpha_{now})/\alpha_{now}, from cosmic microwave background…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Masahiro Nakashima , Kazuhide Ichikawa , Ryo Nagata , Jun'ichi Yokoyama

I review recent constraints on and claimed detections of a time-varying fine-structure constant $\alpha$, and discuss our own work, particularly on the effects of $\alpha$ in the cosmic microwave background and large-scale structure. Our…

Astrophysics · Physics 2007-05-23 C. J. A. P. Martins

We forecast the ability of future CMB and galaxy lensing surveys to constrain variations of the fine structure constant. We found that lensing data, as those expected from satellite experiments as Euclid could improve the constraint from…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Matteo Martinelli , Eloisa Menegoni , Alessandro Melchiorri

We present a summary of recent constraints on the value of the fine-structure constant at the epoch of decoupling from the recent observations made by the Wilkinson Microwave Anisotropy Probe (WMAP) satellite. Within the set of models…

Astrophysics · Physics 2008-11-26 G. Rocha , R. Trotta , C. J. A. P. Martins , A. Melchiorri , P. P. Avelino , P. T. P. Viana

Any variation of the fundamental physical constants, and more particularly of the fine structure constant, $\alpha$, or of the mass of the electron, $m_e$, would affect the recombination history of the Universe and cause an imprint on the…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-11 P. A. R. Ade , N. Aghanim , M. Arnaud , M. Ashdown , J. Aumont , C. Baccigalupi , A. J. Banday , R. B. Barreiro , E. Battaner , K. Benabed , A. Benoit-Lévy , J. -P. Bernard , M. Bersanelli , P. Bielewicz , J. R. Bond , J. Borrill , F. R. Bouchet , C. Burigana , R. C. Butler , E. Calabrese , A. Chamballu , H. C. Chiang , P. R. Christensen , D. L. Clements , L. P. L. Colombo , F. Couchot , A. Curto , F. Cuttaia , L. Danese , R. D. Davies , R. J. Davis , P. de Bernardis , A. de Rosa , G. de Zotti , J. Delabrouille , J. M. Diego , H. Dole , O. Doré , X. Dupac , T. A. Enßlin , H. K. Eriksen , O. Fabre , F. Finelli , O. Forni , M. Frailis , E. Franceschi , S. Galeotta , S. Galli , K. Ganga , M. Giard , J. González-Nuevo , K. M. Górski , A. Gregorio , A. Gruppuso , F. K. Hansen , D. Hanson , D. L. Harrison , S. Henrot-Versillé , C. Hernández-Monteagudo , D. Herranz , S. R. Hildebrandt , E. Hivon , M. Hobson , W. A. Holmes , A. Hornstrup , W. Hovest , K. M. Huffenberger , A. H. Jaffe , W. C. Jones , E. Keihänen , R. Keskitalo , R. Kneissl , J. Knoche , M. Kunz , H. Kurki-Suonio , J. -M. Lamarre , A. Lasenby , C. R. Lawrence , R. Leonardi , J. Lesgourgues , M. Liguori , P. B. Lilje , M. Linden-Vørnle , M. López-Caniego , P. M. Lubin , J. F. Macías-Pérez , N. Mandolesi , M. Maris , P. G. Martin , E. Martínez-González , S. Masi , S. Matarrese , P. Mazzotta , P. R. Meinhold , A. Melchiorri , L. Mendes , E. Menegoni , A. Mennella , M. Migliaccio , M. -A. Miville-Deschênes , A. Moneti , L. Montier , G. Morgante , A. Moss , D. Munshi , J. A. Murphy , P. Naselsky , F. Nati , P. Natoli , H. U. Nørgaard-Nielsen , F. Noviello , D. Novikov , I. Novikov , C. A. Oxborrow , L. Pagano , F. Pajot , D. Paoletti , F. Pasian , G. Patanchon , O. Perdereau , L. Perotto , F. Perrotta , F. Piacentini , M. Piat , E. Pierpaoli , D. Pietrobon , S. Plaszczynski , E. Pointecouteau , G. Polenta , N. Ponthieu , L. Popa , G. W. Pratt , S. Prunet , J. P. Rachen , R. Rebolo , M. Reinecke , M. Remazeilles , C. Renault , S. Ricciardi , I. Ristorcelli , G. Rocha , G. Roudier , B. Rusholme , M. Sandri , G. Savini , D. Scott , L. D. Spencer , V. Stolyarov , R. Sudiwala , D. Sutton , A. -S. Suur-Uski , J. -F. Sygnet , J. A. Tauber , D. Tavagnacco , L. Terenzi , L. Toffolatti , M. Tomasi , M. Tristram , M. Tucci , J. -P. Uzan , L. Valenziano , J. Valiviita , B. Van Tent , P. Vielva , F. Villa , L. A. Wade , D. Yvon , A. Zacchei , A. Zonca

The formation of the cosmic microwave background radiation (CMBR) provides a very powerful probe of the early universe at the epoch of recombination. Specifically, it is possible to constrain the variation of fundamental physical constants…

Astrophysics · Physics 2009-10-31 Steen Hannestad

We demonstrate that recent measurements of Cosmic Microwave Background temperature and polarization anisotropy made by the ACBAR, QUAD and BICEP experiments substantially improve the cosmological constraints on possible variations of the…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-28 Eloisa Menegoni , Silvia Galli , James Bartlett , Carlos J. A. P. Martins , Alessandro Melchiorri

We study the role of fundamental constants in an updated recombination scenario. We focus on the time variation of the fine structure constant, and the electron mass in the early Universe, and put bounds on these quantities by using data…

Astrophysics · Physics 2008-10-31 Claudia G. Scóccola , Susana. J. Landau , Hector Vucetich

We discuss how laboratory experiments can be used to place constraints on possible variations of the fine structure constant alpha in the observationally relevant redshift interval z ~= 0 - 5, within a rather general theoretical framework.…

Astrophysics · Physics 2009-10-30 Mario Livio , Massimo Stiavelli

We update the constraints on the time variation of the fine structure constant $\alpha$ and the electron mass $m_e$, using the latest CMB data, including the 7-yr release of WMAP. We made statistical analyses of the variation of each one of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Susana. J. Landau , Claudia G. Scóccola

We extend our recent work on the effects of a time-varying fine-structure constant $\alpha$ in the cosmic microwave background, by providing a thorough analysis of the degeneracies between $\alpha$ and the other cosmological parameters, and…

We present up-to-date constraints on the value of the fine-structure constant at the epoch of decoupling from the recent observations made by the Wilkinson Microwave Anisotropy Probe (WMAP) satellite. In the framework of models we…

Astrophysics · Physics 2008-11-26 C. J. A. P. Martins , A. Melchiorri , G. Rocha , R. Trotta , P. P. Avelino , P. Viana

We present a detailed analysis of present and future Cosmic Microwave Background constraints of the value of the fine-structure constant, $\alpha$. We carry out a more detailed analysis of the WMAP first-year data, deriving state-of-the-art…

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

We present updated constraints on the variation of the fine structure constant, $\alpha_{\rm EM}$, and effective electron rest mass, $m_{\rm e}$, during the cosmological recombination era. These two fundamental constants directly affect the…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-25 Luke Hart , Jens Chluba

Some attempts of easing the critical Hubble tension present in modern cosmology have resorted to using variations of fundamental constants, such as the fine-structure constant, at the time of recombination. In this article we demonstrate…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-22 Léo Vacher , Nils Schöneberg

Higher-dimensional theories have the remarkable feature of predicting a time (and hence redshift) dependence of the `fundamental' four dimensional constants on cosmological timescales. In this paper we update the bounds on a possible…

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