Summary: Is the velocity of light a fixed constant of nature, invariant over time? This page presents the available measurements of c and several statistical studies which suggest that c has decreased in the past 300 years. What other "constants" of physics might prove to be non-fixed? How would a non-constant c affect physical laws? Possible consequences for cosmology and the age of the universe. Responses and comments are solicited.

Of Special Interest

Related Web Links Concerning the Constants of Physics

Speed of Light (Basic Information and Measurement Methods)

The laws list (Laws of Physics)

Physical Reference Data (NIST)

The Speed of Light - A Limit on Principle? (Laro Schatzer, Swiss Physicist)

Alexander Shlyakhter (Oklo reactor, fundamental constants, cosmology, fine-structure constant, neutron cross sections)

Notes and Links on Leap Seconds (various sources)

Notes on the Quantization of the Red-Shifted Light from Distant Galaxies

The Fine Structure Constant, by James Gilson

On the Speed of Gravity

The Speed of Gravity - What the Experiments Say, by Tom Van Flandern

There was once a young man from Wight
Who could travel faster than the speed of light.
He went out one day
In a relative way
And returned home the previous night.

On the Constancy of the Velocity of Light

Barry Setterfield's Library | Lambert Dolphin's Library Last update 8/13/03.


spelling and punctuation checked 27June02 RPS