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arXiv · 1008.3907

Indications of a spatial variation of the fine structure constant

J. K. Webb·J. A. King·M. T. Murphy·V. V. Flambaum·R. F. Carswell·M. B. Bainbridge
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Abstract

We previously reported Keck telescope observations suggesting a smaller value of the fine structure constant, alpha, at high redshift. New Very Large Telescope (VLT) data, probing a different direction in the universe, shows an inverse evolution; alpha increases at high redshift. Although the pattern could be due to as yet undetected systematic effects, with the systematics as presently understood the combined dataset fits a spatial dipole, significant at the 4.2-sigma level, in the direction right ascension 17.5 +/- 0.9 hours, declination -58 +/- 9 degrees. The independent VLT and Keck samples give consistent dipole directions and amplitudes, as do high and low redshift samples. A search for systematics, using observations duplicated at both telescopes, reveals none so far which emulate this result.

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J. K. Webb, J. A. King, M. T. Murphy, V. V. Flambaum, R. F. Carswell, M. B. Bainbridge. 2011-11-01. Indications of a spatial variation of the fine structure constant. https://doi.org/10.1103/physrevlett.107.191101

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