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A reanalysis of quasar absorption spectra results suggesting a spatial gradient in values of the fine-structure constant

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 نشر من قبل Julian Berengut
 تاريخ النشر 2012
  مجال البحث فيزياء
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We statistically analyse a recent sample of data points measuring the fine-structure constant alpha (relative to the terrestrial value) in quasar absorption systems. Using different statistical techniques, we find general agreement with previous authors that a dipole model is a well-justified fit to the data. We determine the significance of the dipole fit relative to that of a simple monopole fit, discuss the consistency of the interpretation, and test alternate models for potential variation of alpha against the data. Using a simple analysis we find that the monopole term (the constant offset in (delta alpha)/alpha) may be caused by non-terrestrial magnesium isotope abundances in the absorbers. Finally we test the domain-wall model against the data.



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