New constraints on varying α

@article{Rocha2003NewCO,
title={New constraints on varying $\alpha$},
author={Graca M. Rocha and Richard Trotta and Carlos J. A. P. Martins and Alessandro Melchiorri and P. P. Avelino and Pedro T. P. Viana},
journal={New Astronomy Reviews},
year={2003},
volume={47},
pages={863-869}
}
• Published 6 September 2003
• Physics
• New Astronomy Reviews

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References

SHOWING 1-10 OF 32 REFERENCES
Early universe constraints on a time varying fine structure constant
• Physics
• 2001
Higher-dimensional theories have the remarkable feature of predicting a time (and hence redshift) dependence of the `fundamental' four dimensional constants on cosmological timescales. In this paper
Measuring $α$ in the Early Universe: CMB Temperature, Large-Scale Structure and Fisher Matrix Analysis
• Physics
• 2002
We extend our recent work on the effects of a time-varying fine-structure constant $\alpha$ in the cosmic microwave background, by providing a thorough analysis of the degeneracies between $\alpha$
Further evidence for cosmological evolution of the fine structure constant.
• Physics
Physical review letters
• 2001
The results of a search for time variability of the fine structure constant alpha using absorption systems in the spectra of distant quasars find no systematic effects which can explain the results.
Looking for a varying a in the cosmic microwave background
• Physics
• 2000
We perform a likelihood analysis of the recently released BOOMERanG and MAXIMA data, allowing for the possibility of a time-varying fine-structure constant. We find that in general this data prefers
Constraining variations in the fine structure constant with the cosmic microwave background
• Physics
• 1999
Any time variation in the fine-structure constant alters the ionization history of the universe and therefore changes the pattern of cosmic microwave background fluctuations. We calculate the changes
Does the fine structure constant vary? A third quasar absorption sample consistent with varying α
• Physics
• 2002
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. This
The fundamental constants and their variation: observational and theoretical status
This article describes the various experimental bounds on the variation of the fundamental constants of nature. After a discussion of the role of fundamental constants, their definition and link with
A New Calculation of the Recombination Epoch
• Physics
• 1999
We have developed an improved recombination calculation of H, He I, and He II in the early universe that involves a line-by-line treatment of each atomic level. We find two major differences compared
Does the proton-to-electron mass ratio μ = mp/me vary in the course of cosmological evolution?
• Physics
• 2002
The possible cosmological variation of the proton-to-electron mass ratio μ = mp/me was estimated by measuring the H2 wavelengths in the high-resolution spectrum of the quasar Q 0347-382. Our analysis
Behavior of varying-alpha cosmologies
• Physics
• 2002
We determine the behaviour of a time-varying fine structure 'constant' $\alpha (t)$ during the early and late phases of universes dominated by the kinetic energy of changing $\alpha (t)$, radiation,