In 1972, Scientists Discovered a Two Billion-Year-Old Nuclear Reactor In Gabon
> Davis and co point out that the Oklo data can also constrain changes in other constants, such as the ratio of light quark masses to the proton mass. To date, this work is consistent with these constants being constant.<p>In the history of science, how many 'constants' have, so far, been shown not to be constant?