J. K. Webb

Further evidence for cosmological evolution of the fine structure constant

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 find no systematic effects which can explain our results. The only potentially significant systematic effects push Delta alpha/alpha towards positive values; i.e., our results would become more significant were we to correct for them.

Search for time variation of the fine structure constant

An order of magnitude sensitivity gain is described for using quasar spectra to investigate possible time or space variation in the fine structure constant

Further evidence for a variable fine‐structure constant from Keck/HIRES QSO absorption spectra

\ensuremath{\alpha}

Indications of a spatial variation of the fine structure constant.

. Applied to a sample of 30 absorption systems, spanning redshifts

Possible evidence for a variable fine-structure constant from QSO absorption lines: motivations, analysis and results

0.5lzl1.6

The Origin of C IV Absorption Systems at Redshifts z < 1: Discovery of Extended C IV Envelopes around Galaxies*

, we derive limits on variations in

The Gaseous Extent of Galaxies and the Origin of Lyα Absorption Systems. V. Optical and Near-Infrared Photometry of Lyα-absorbing Galaxies at z < 1*

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An Assessment of Grip Strength Measurement in Rheumatoid Arthritis

over a wide range of epochs. For the whole sample,

The Gaseous Extent of Galaxies and the Origin of Ly? Absorption Systems. III. Hubble Space Telescope Imaging of Ly?-absorbing Galaxies at z < 1

\ensuremath{\Delta}\ensuremath{\alpha}/\ensuremath{\alpha}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}(\ensuremath{-}1.1\ifmmode\pm\else\textpm\fi{}0.4)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}

Revision of VLT/UVES constraints on a varying fine‐structure constant

. This deviation is dominated by measurements at