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Brax, Ph.; Bruck, Carsten van de; Davis, Anne-Christine; Rhodes, C. S.

doi:10.1023/a:1022543206870

Cited by 69 publications

(91 citation statements)

References 4 publications

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“…[26] and references therein). It has also been suggested, however, that the chameleon field arises from the compactification of extra dimensions, [27]. In this case, there is no particular reason why the true Planck scale (i.e.…”

Section: The Models a Chameleon Modelmentioning

confidence: 99%

Detecting chameleons: The astronomical polarization produced by chameleonlike scalar fields

2009

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We show that a coupling between chameleon-like scalar fields and photons induces linear and circular polarization in the light from astrophysical sources. In this context chameleon-like scalar fields includes those of the Olive-Pospelov (OP) model, which describes a varying fine structure constant. We determine the form of this polarization numerically and give analytic expressions in two useful limits. By comparing the predicted signal with current observations we are able to improve the constraints on the chameleon-photon coupling and the coupling in the OP model by over two orders of magnitude. It is argued that, if observed, the distinctive form of the chameleon induced circular polarization would represent a smoking gun for the presence of a chameleon. We also report a tentative statistical detection of a chameleon-like scalar field from observations of starlight polarization in our galaxy.

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Section: The Models a Chameleon Modelmentioning

confidence: 99%

Detecting chameleons: The astronomical polarization produced by chameleonlike scalar fields

2009

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“…Several theories that attempt to unify the four fundamental interactions, such as superstrings (Wu & Wang 1986;Barr & Mohapatra 1988;Maeda 1988;Damour & Polyakov 1994;Damour et al 2002a,b), brane world (Youm 2001a,b;Brax et al 2003;Palma et al 2003) and Kaluza-Klein theories (Kaluza 1921;Klein 1926;Weinberg 1983;Gleiser & Taylor 1985;Overduin & Wesson 1997), allow fundamental constants to vary within cosmological time scales. The time variation of several fundamental constants was studied by Campbell & Olive (1995), Bergström et al (1999), Ichikawa & Kawasaki (2002), Nollett & Lopez (2002), Yoo & Scherrer (2003), Müller et al (2004), Ichikawa & Kawasaki (2004), Cyburt et al (2005), Landau et al (2006), Coc et al (2007), Chamoun et al (2007), Mosquera et al (2008), Landau et al (2008), Landau & Scóccola (2010), , Civitarese et al (2010), among others.…”

Section: Introductionmentioning

confidence: 99%

Time variation of the fine structure constant and of the Higgs vacuum expectation value on cosmological time scales

Mosquera

Civitarese

2011

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Aims. We study the time variation of both the fine structure constant, α, and the Higgs vacuum expectation value, v, during Big Bang nucleosynthesis (BBN). Methods. We calculate the primordial abundances of D, 4 He, and 7 Li by modifying Kawano's code, and by using observational data we set constraints on the joint variation of α and v. To perform the calculations we considered the dependence of the deuteriumbinding energy, D , upon v, obtained from the treatment of different proton-neutron interactions. Results. Results are consistent with variation on v (even at the level of 6σ) and null variation of α (within 2σ) if the 7 Li data are used in the analysis. However, if data on these nuclei are not considered in the statistical analysis, we found null variation on both fundamental constants within 2σ. Conclusions. We found that the best-fit values of the variation of v and α are sensible to the dependence of the deuterium binding energy upon the Higgs vacuum expectation value. We found non-null variation of v within 6σ if all the observational data are used in the analysis. If data on the primordial abundance of 7 Li are taken at face value, the discrepancy between BBN and WMAP estimates may be explained by allowing variations of v.

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“…Since BBN is sensible to parameters such as the fine structure constant, the electron mass, the Higgs vacuum expectation value (v), the deuterium binding energy ( D ), among others, it is an important test to set constraints on deviations from the standard cosmology, and on physical theories beyond the standard model (SM). There are some theories which allow fundamental constants to vary over cosmological times scales (Kaluza 1921;Klein 1926;Weinberg 1983;Gleiser & Taylor 1985;Wu & Wang 1986;Barr & Mohapatra 1988;Maeda 1988;Damour & Polyakov 1994;Overduin & Wesson 1997;Youm 2001a,b;Damour et al 2002a,b;Brax et al 2003;Palma et al 2003). The time variation of fundamental constants (e.g.…”

Section: Introductionmentioning

confidence: 99%

Effect of the variation of the Higgs vacuum expectation value upon the deuterium binding energy and primordial abundances of D and⁴He

Mosquera

Civitarese

2010

A&A

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Aims. We calculate the constraints on the time variation of the Higgs vacuum expectation value from Big Bang Nucleosynthesis. Methods. Starting from the calculation of the deuterium binding-energy, as a function of the pion-mass and using the NN-Reid 93 potential, we calculate the abundances of primordial D and 4 He by modifying Kawano's code. The Higgs vacuum expectation value (v) and the baryon to photon ratio (η B ) enter the calculation as free parameters. By using the observational data of D and 4 He, we set constraints on η B and on the variation of v, relative to a constant value of Λ QCD . Results. Results are consistent with null variation in v and D for the early universe, within 6σ. Conclusions. We obtained a linear dependence of D upon v and found that the best-fit-value of the variation of v is null within 6σ.

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Cited by 69 publications

References 4 publications

Detecting chameleons: The astronomical polarization produced by chameleonlike scalar fields

Detecting chameleons: The astronomical polarization produced by chameleonlike scalar fields

Time variation of the fine structure constant and of the Higgs vacuum expectation value on cosmological time scales

Effect of the variation of the Higgs vacuum expectation value upon the deuterium binding energy and primordial abundances of D and⁴He

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Cited by 69 publications

References 4 publications

Detecting chameleons: The astronomical polarization produced by chameleonlike scalar fields

Detecting chameleons: The astronomical polarization produced by chameleonlike scalar fields

Time variation of the fine structure constant and of the Higgs vacuum expectation value on cosmological time scales

Effect of the variation of the Higgs vacuum expectation value upon the deuterium binding energy and primordial abundances of D and4He

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Effect of the variation of the Higgs vacuum expectation value upon the deuterium binding energy and primordial abundances of D and⁴He