'Hover over the picture above to see the watch working'
What is the evidence for the invariance of the speed of light? If you're not totally sure of the answer to this question then please don't ask us, it's not that we don't know but that it would take too long to explain (honest).
If you have the slightest understanding of Relativity or any of Einstein's theories then you might appreciate this 'Relativity watch'. Instead of the hands rotating around the watch over the numbers the hands actually stay still whilst the numbers rotate around the watch. A non-relative watch!
Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.
Albert Einstein US (German-born) physicist (1879 - 1955)