Further evidence for cosmological evolution of the fine structure constant.

  title={Further evidence for cosmological evolution of the fine structure constant.},
  author={John K Webb and Michael Murphy and Victor V. Flambaum and V. A. Dzuba and John D. Barrow and Christopher W. Churchill and J. Xavier Prochaska and Arthur M. Wolfe},
  journal={Physical review letters},
  volume={87 9},
We describe the results of a search for time variability of the fine structure constant alpha using absorption systems in the spectra of distant quasars. Three large optical data sets and two 21 cm and mm absorption systems provide four independent samples, spanning approximately 23% to 87% of the age of the universe. Each sample yields a smaller alpha in the past and the optical sample shows a 4 sigma deviation: Delta alpha/alpha = -0.72+/-0.18 x 10(-5) over the redshift range 0.5<z<3.5. We… Expand

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