(adsbygoogle = window.adsbygoogle || []).push({}); What's Dirac's Large Number Hypothesis ???

In 1938, Dirac noted that the ratio of the electrostatic force between and electron and a proton to their gravitational attraction was approximately equal to the ratio of the size of the universe to the size of an electron )[itex]10^{-20} [/itex] cm.

[tex] \frac{F_{elec}}{F_{grav}} \sim \frac{Size_u}{Size_e} \sim 10^{39} [/tex]

If we equate the gravitational acceleration of some mass, m, to the centripetal acceleration which depends on the velocity of this mass and as this velocity approaches the speed of light in vacuum then this mass is related to a large number product with radius of circular motion.

[tex] m = \left( \frac{c^2}{G} \right) r [/tex]

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# What's Dirac's Large Number Hypothesis ?

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