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Do the Fundamental Constants Vary in the Course of the Cosmological Evolution?

A. Ivanchik·E. Rodriguez·P. Petitjean·D. Varshalovich
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Abstract

We estimate the cosmological variation of the proton-to-electron mass ratio μ=m_p/m_e by measuring the wavelengths of molecular hydrogen transitions in the early universe. The analysis is performed using high spectral resolution observations (FWHM ~ 7 km/s) of two damped Lyman-αsystems at z_{abs}=2.3377 and 3.0249 observed along the lines of sight to the quasars Q 1232+082 and Q 0347-382 respectively. The most conservative result of the analysis is a possible variation of μover the last ~ 10 Gyrs, with an amplitude Δμ/μ= (5.7+-3.8)x10^{-5}. The result is significant at the 1.5σlevel only and should be confirmed by further observations. This is the most stringent estimate of a possible cosmological variation of μobtained up to now.

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A. Ivanchik, E. Rodriguez, P. Petitjean, D. Varshalovich. 2002-01-14. Do the Fundamental Constants Vary in the Course of the Cosmological Evolution?. https://doi.org/10.1134/1.1491963

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