# New varying speed of light theories

@article{Magueijo2003NewVS, title={New varying speed of light theories}, author={Jo{\~a}o Magueijo}, journal={Reports on Progress in Physics}, year={2003}, volume={66}, pages={2025-2068} }

We review recent work on the possibility of a varying speed of light (VSL). We start by discussing the physical meaning of a varying-c, dispelling the myth that the constancy of c is a matter of logical consistency. We then summarize the main VSL mechanisms proposed so far: hard breaking of Lorentz invariance; bimetric theories (where the speeds of gravity and light are not the same); locally Lorentz invariant VSL theories; theories exhibiting a colour-dependent speed of light; varying-c…

## 230 Citations

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