c is the speed of light, isn't it?
Abstract
Theories for a varying speed of light have been proposed as an alternative way of solving several standard cosmological problems. Recent observational hints that the fine structure constant may have varied over cosmological scales have given impetus to these theories. However, the speed of light is hidden in many physics equations and plays different roles in them. We discuss these roles to shed light on proposals for varying speed of light theories. We also emphasize the requirements for attaining consistency of the resulting equations, when what was previously a constant is made a dynamical variable.
 Publication:

American Journal of Physics
 Pub Date:
 March 2005
 DOI:
 10.1119/1.1819929
 arXiv:
 arXiv:grqc/0305099
 Bibcode:
 2005AmJPh..73..240E
 Keywords:

 01.40.d;
 98.80.k;
 03.30.+p;
 Education;
 Cosmology;
 Special relativity;
 General Relativity and Quantum Cosmology;
 Astrophysics;
 High Energy Physics  Theory
 EPrint:
 14 pages, Latex