------------------------------------------------------ Uncertainty in the Universal Gravitational Constant G. ------------------------------------------------------
I remember once reading a book or paper, I forget which, where the chap was pondering on why the universal gravitational constant, G, was one of the most poorly defined fundamental constants. In my 1968 coy if Kaye and Laby's Tables of physical and chemical constants the value is given as 6.670_10^-8_cm^3_g^-1_s^-2 In the margin of K&L I have a pencilled note that the value of G in the 1973 edition is 6.673. When I looked up G on the internet I got a value of 6.672. Now I wonder....Could it just be the lack of precision in G is because G isn't actually a constant at all, but is really a variable? Possibly variation in inertial mass with change in velocity -> Leo gives rise to a second order perturbation in gravitational mass. Perhaps we ought to couple the word "allegedly", to the word "constant". Still, it shouldn't be too difficult to sort it out one way or the other since G should vary with the seasons. Trouble is, any variation like that would have been in great danger of being seen as an artifact. Indeed as a blasphemy on the divine Newton. Still, it would be very interesting to examine the history of G measurement to find what it reveals. Cheers Grimer
