Further evidence for cosmological evolution of the fine structure constant.

@article{Webb2001FurtherEF,
  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},
  year={2001},
  volume={87 9},
  pages={
          091301
        }
}
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

Figures and Tables from this paper

Possible evidence for a variable fine-structure constant from QSO absorption lines: systematic errors
Comparison of quasar (QSO) absorption spectra with laboratory spectra allows us to probe possible variations in the fundamental constants over cosmological time-scales. In a companion paper weExpand
Constraining the cosmological time variation of the fine - structure constant
The variation of the fine-structure constant α = e2 / ħc can be probed by comparing the wavelength of atomic transitions from the redshift of quasars in the Universe and laboratory over cosmologicalExpand
New Limit on the Spatial and Temporal Variations of the Fine-Structure Constant Using High Redshifts of Quasar Spectra
Highly precise measurements on the light from distant quasars can served as a powerful tool to test the possible spatial and temporal variations of the fine-structure constant α = e2 /c during theExpand
Does the fine structure constant vary? A third quasar absorption sample consistent with varying α
We report results from a third sample of quasar absorption line spectra from the Keck telescope which has been studied to search for any possible variation of the fine structure constant, α. ThisExpand
A new analysis of fine-structure constant measurements and modelling errors from quasar absorption lines
We present an analysis of 23 absorption systems along the lines of sight towards 18 quasars in the redshift range of 0.4 6 zabs 6 2.3 observed on the Very Large Telescope (VLT) using the UltravioletExpand
Constraining variations in the fine-structure constant, quark masses and the strong interaction
We present evidence for variations in the fine-structure constant from Keck/HIRES spectra of 143 quasar absorption systems over the redshift range 0.2 1.8). Our most robust estimate is a weightedExpand
Does the fine structure constant vary? A detailed investigation into systematic effects
We have previously presented 5.7 σ evidence for a smaller αat redshifts 0.2 < zabs < 3.7 from a sample of 128 Keck/HIRES quasar absorption systems: Δα/α = (-0.57 ± 0.10) x10-5. A non-zero <Δα/αExpand
Spatial variation in the fine-structure constant – new results from VLT/UVES
Quasar absorption lines provide a precise test of whether the fine-structure constant, α, is the same in different places and through cosmological time. We present a new analysis of a large sample ofExpand
Constraining Fundamental Constants of Physics with Quasar Absorption Line Systems
We summarize the attempts by our group and others to derive constraints on variations of fundamental constants over cosmic time using quasar absorption lines. Most upper limits reside in the rangeExpand
Does the Fine-Structure Constant Vary with Cosmological Epoch?
We use the strong nebular emission lines of O III, ??5007 and 4959, to set a robust upper limit on the time dependence of the fine-structure constant. We find < 2 ? 10-13 yr-1, corresponding toExpand
...
1
2
3
4
5
...