Do the fundamental constants change with time ?

Abstract

Comparisons between the redshifts of spectral lines from cosmologically-distant galaxies can be used to probe temporal changes in low-energy fundamental constants like the fine structure constant and the proton-electron mass ratio. In this article, I review the results from, and the advantages and disadvantages of, the best techniques using this approach, before focussing on a new method, based on conjugate satellite OH lines, that appears to be less affected by systematic effects and hence holds much promise for the future.

15 pages, 3 figures. This is an electronic version of an invited review article for Mod. Phys. Lett. A, published as [Mod. Phys. Lett. A, Vol. 23, No. 32, 2008, pp. 2711] (copyright World Scientific Publishing Company; http://www.worldscientific.com/)

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Cited by in corpus (10)

• Keck telescope constraint on cosmological variation of the proton-to-electron mass ratio
• Constraining changes in the proton-electron mass ratio with inversion and rotational lines
• A search for HI 21cm absorption in strong MgII absorbers in the redshift desert
• Constraining fundamental constant evolution with HI and OH lines
• Probing fundamental constant evolution with neutral atomic gas lines
• Gyromagnetic Factors and Atomic Clock Constraints on the Variation of Fundamental Constants
• Probing fundamental constant evolution with redshifted conjugate-satellite OH lines
• Competing bounds on the present-day time variation of fundamental constants
• Searching for spatial variations of alpha^2/mu in the Milky Way
• The value of the fine structure constant over cosmological times