[thechat] Speed of light may have changed recently

[Madhu Menon]

http://www.newscientist.com/news/news.jsp

<quote>


The speed of light, one of the most sacrosanct of the universal physical 
constants, may have been lower as recently as two billion years ago - and 
not in some far corner of the universe, but right here on Earth.

The controversial finding is turning up the heat on an already simmering 
debate, especially since it is based on re-analysis of old data that has 
long been used to argue for exactly the opposite: the constancy of the 
speed of light and other constants.

A varying speed of light contradicts Einstein's theory of relativity, and 
would undermine much of traditional physics. But some physicists believe it 
would elegantly explain puzzling cosmological phenomena such as the nearly 
uniform temperature of the universe. It might also support string theories 
that predict extra spatial dimensions.

</quote>


Will the physicists on this list please explain the rest of the article in 
plain English? My high-school physics is more than a decade old and hence, 
rusty. Alan?

Regards,

Madhu