Cosmologies with varying light speed
Abstract
We analyze a generalization 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 Magueijo. 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 are highlighted. Reformulations are suggested which give the theory a more desirable limit as a theory of varying G in the limit of constant c and its relationship to theories with varying electron charge and constant c are discussed.
 Publication:

Physical Review D
 Pub Date:
 February 1999
 DOI:
 10.1103/PhysRevD.59.043515
 arXiv:
 arXiv:astroph/9811022
 Bibcode:
 1999PhRvD..59d3515B
 Keywords:

 98.80.Cq;
 95.30.Sf;
 Particletheory and fieldtheory models of the early Universe;
 Relativity and gravitation;
 Astrophysics;
 General Relativity and Quantum Cosmology
 EPrint:
 latex file. 19 pages