XIème Ecole de Cosmologie
17 - 22 septembre 2012 IESC, Cargèse
 Lentilles gravitationnelles
leur impact dans l’étude des galaxie et la cosmologie

Constraints on variation of fundamental constants from Cosmology

Eloisa MENEGONI
University of Rome Sapienza

Poster

Résumé : In about six refereed papers [7][10][12][13][14][15], I investigated the value of nature’s fundamental couplings in the early universe, considering possible deviations from the current standard values. A time varying fine structure constant can leave an imprint on CMB anisotropies by changing the time of recombination and the size of the acoustic horizon at photon-electron decoupling (see [1],[2],[3],[4]). The CMB datasets have been extensively used to constrain α by parametraizing a variation in the fine structure constant as Δα = (α - α0)∕α0, where α0 is the standard, local value and α is the value during the recombination process[5],[6]. By performing a MCMC analysis and using WMAP-5 years data, and I found α∕α0 = 0.998 ± 0.021 at 68% c.l., the constraints are much tighter if you also include all the CMB data plus a prior on the value of Hubble constant, in this case I found α∕α0 = 1.001 ± 0.007 [7].
By including early dark energy component [11], the variations of the fine structure constant using WMAP-7 years data and HST data give α∕α0 = 0.963 ± 0.044, Ωe < 0.064 and for the coupling ζ < 0.047 at 95%c.l.. By performing a Fisher matrix analysis and using Planck and CMBPol experimental specifications I found better and strong constraints on the parameter: for Planck σ(α∕α0) = 0.0012, σ(Ωe) = 0.0036, σ(ζ) < 0.0012 and the results for CMBPol σ(α∕α0) = 0.00025, σ(Ωe) = 0.0015 and σ(ζ) < 0.00022 [12].
Bibliographie
    • (1] Steen Hannestad. Phys.Rev. D60 (1999) 023515 DOI: 10.1103/PhysRevD.60.023515 Cite as: arXiv:astro-ph/9810102v2 .[2]   Manoj Kaplinghat, Robert J. Scherrer, Michael S. Turner. Phys.Rev. D60 (1999) 023516 DOI: 10.1103/PhysRevD.60.023516 Cite as: arXiv:astro-ph/9810133v2 .
    • [3]   R.A. Battye, R. Crittenden, J. Weller. Phys.Rev. D63 (2001) 043505 DOI: 10.1103/PhysRevD.63.043505 Cite as: arXiv:astro-ph/0008265v1.
    • [4]   P.P. Avelino, S. Esposito, G. Mangano, C.J.A.P. Martins, A. Melchiorri, G. Miele, O. Pisanti, G. Rocha, P.T.P. Viana. Phys.Rev.D64:103505,2001 DOI: 10.1103/PhysRevD.64.103505 Report number: DAMTP-2001-13, DSF-5-2001 Cite as: arXiv:astro-ph/0102144v4.
    • [5]   C.J.A.P.Martins , A. Melchiorri , G. Rocha , R. Trotta , P.P. Avelino , P. Viana . Phys.Lett.B585:29-34,2004 DOI: 10.1016/j.physletb.2003.11.080 Report number: DAMTP-2003-13 Cite as: arXiv:astro-ph/0302295v2.
    • [6]   G. Rocha (Cambridge, CAUP), R. Trotta (Geneva), C.J.A.P. Martins (CAUP, Cambridge, IAP), A. Melchiorri (Oxford), P.P. Avelino (Porto), P.T.P. Viana (CAUP). NewAstron.Rev.47:863-869,2003 DOI: 10.1016/j.newar.2003.07.018 Cite as: arXiv:astro-ph/0309205v1.
    • [7]   Eloisa Menegoni, Silvia Galli, James Bartlett, Carlos J. A. P. Martins, Alessandro Melchiorri. Phys.Rev.D80:087302,2009 DOI: 10.1103/PhysRevD.80.087302 Cite as: arXiv:0909.3584v1 [astro-ph.CO].
    • [8]   P. Loren-Aguilar, E. Garcia-Berro, J. Isern, Yu.A. Kubyshin. Class.Quant.Grav.20:3885-3896,2003 DOI: 10.1088/0264-9381/20/18/302 Cite as: arXiv:astro-ph/0309722v1.
    • [9]   E. Garcia-Berro, J. Isern and Y. A. Kubyshin,. Astron. Astrophys. Rev. 14, 113 (2007).
    • [10]   C.J.A.P. Martins, Eloisa Menegoni, Silvia Galli, Gianpiero Mangano, Alessandro Melchiorri. Phys.Rev.D82:023532,2010 DOI: 10.1103/PhysRevD.82.023532 Cite as: arXiv:1001.3418v3 [astro-ph.CO].
    • [11]   Erminia Calabrese, Roland de Putter, Dragan Huterer, Eric V. Linder, Alessandro Melchiorri. Phys.Rev.D83:023011,2011 DOI: 10.1103/PhysRevD.83.023011 Cite as: arXiv:1010.5612v1 [astro-ph.CO].
    • [12]   Erminia Calabrese, Eloisa Menegoni, C.J.A.P. Martins, Alessandro Melchiorri, Graca Rocha. Phys.Rev.D84:023518,2011 DOI: 10.1103/PhysRevD.84.023518 Cite as: arXiv:1104.0760v1 [astro-ph.CO].
    • [13]   2009 ”‘Constraints on the dark energy equation of state in presence of a varying fine structure constant”’ (IJMPD, International Journal of Modern Physics D, Volume 19, Issue 04, pp. 507-512 2010). E. Menegoni, S. Pandolfi, S. Galli, M. Lattanzi, A. Melchiorri.
    • [14]   ”The Fine Structure Constant and the CMB Damping Scale”, Eloisa Menegoni, Maria Archidiacono, Erminia Calabrese, Silvia Galli, C. J. A. P. Martins, Alessandro Melchiorri. Cite as: arXiv:1202.1476v1 [astro-ph.CO].
    • [15]   ”Future constraints on variations of the fine structure constant from combined CMB and weak lensing measurements” Matteo Martinelli, Eloisa Menegoni, Alessandro Melchiorri. Cite as: arXiv:1202.4373v2 [astro-ph.CO].

Programme