Comment by rramadass
6 hours ago
Just to clarify; The term "2 x 109" is actually "2 x 10^9" or 2 billion years which was considered the present epoch i.e. accepted age of the universe at that time.
Dirac large numbers hypothesis - https://en.wikipedia.org/wiki/Dirac_large_numbers_hypothesis
Correct (but now we know it should be somewhat higher than that), and 1039 should be 10^39, one of Dirac's Large Numbers, the size of the observable universe in atomic units, and also the ratio of electromagnetic to gravitational forces in the hydrogen atom.
Right. Added the wikipedia link to Dirac's LNH above.
Also found this; The fundamental constants and their variation: observational status and theoretical motivations - https://arxiv.org/abs/hep-ph/0205340