How constant are the physical constants?
Beginning with Paul Dirac in 1937, some scientists have speculated that physical constants may actually decrease in proportion to the age of the universe. Scientific experiments have not yet pinpointed any definite evidence that this is the case, although they have placed upper bounds on the maximum possible relative change per year at very small amounts (roughly 10−5 per year for the fine structure constant α and 10−11 for the gravitational constant G). Paul Adrien Maurice Dirac, OM, FRS (IPA: [dɪræk]) (August 8, 1902 â October 20, 1984) was a British theoretical physicist and a founder of the field of quantum physics. … Year 1937 (MCMXXXVII) was a common year starting on Friday (link will display the full calendar) of the Gregorian calendar. … It is currently disputed [2] [3] that any changes in dimensionful physical constants such as G, c, ħ, or ε0 are operationally meaningful;[1] however, a sufficient change in a dimensionless constant such as α is generally agreed to be some
