The fact that light travels at the same speed in all frames of reference is one of the greatest revelations of modern science.
John's book "Lightspeed: The Ghostly Aether and the Race to Measure the Speed of Light" is available now: https://geni.us/3NJlCIB

How have physicists from the ancient Greeks to Einstein tackled the problem of how light travels and what discoveries did it lead them to along the way? John Spence tells the stories of some of the greatest experimental scientists in history as they searched in vain for the mysterious 'aether' and a frame of absolute rest in the universe.

Watch the Q&A:    • Q&A: How We Have Measured the Speed o...  

Prof John C.H. Spence is a Fellow of the Royal Society and the Richard Snell Professor of Physics and a Regents Professor at Arizona State University. He is also the director of science for the NSF BioXFEL Science and Technology Center on the application of X-Ray Free-electron lasers to structural biology.

This talk was filmed in the Ri on 11 March 2020.

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