# Cosmologies with varying light speed

@article{Barrow1999CosmologiesWV, title={Cosmologies with varying light speed}, author={John D. Barrow}, journal={Physical Review D}, year={1999}, volume={59}, pages={043515} }

We analyse a generalisation of general relativity that incorporates a cosmic time-variation of the velocity of light in vacuum, $c,$ and the Newtonian gravitation 'constant', $G,$ proposed by Albrecht and Maguejo. We find exact solutions for Friedmann universes and determine the rate of variation of $c$ required to solve the flatness and classical cosmological constant problems. Potential problems with this approach to the resolution of the flatness and classical cosmological constant problems…

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## References

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A Time varying speed of light as a solution to cosmological puzzles

- Physics
- 1999

We consider the cosmological implications of light travelling faster in the early Universe. We propose a prescription for deriving corrections to the cosmological evolution equations while the speed…

Varying-α theories and solutions to the cosmological problems

- Physics
- 1998

Abstract If the fine structure constant α = e 2 /(ℏ c ) were to change, then a number of interpretations would be possible, attributing this change either to variations in the electron charge, the…