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What's Dirac's Large Number Hypothesis ?

  1. Jul 7, 2004 #1
    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]
  2. jcsd
  3. Jul 7, 2004 #2
    Could be that everything has a wavefunction limit, every particle has a finite 'Horizon', the limit of which is scale dependant?

    The size 'apparent', of the Universe is not fully known. therefore the any ratio of Universe size must be governed by an actual particle, not by the actual Universe.

    Particles may know the size of the Universe in relation to themselves?
  4. Jul 7, 2004 #3
    Based on the large number hypothesis, the size of the universe is roughly 10 billions light-years across. What is the corresponding increase in distance for a degree decrease in temperature?
  5. Jul 7, 2004 #4
    size considerations concern only the observable universe- the actual volume is almost certainly infinite/transfinite based on all the evidence we have-


    /:set\AI transmedia laboratories

  6. Jul 7, 2004 #5
    The equation [itex] m = \left( \frac{c^2}{G} \right) r [/itex] implies that [itex]r[/itex] is equal to 1/2 the Schwarzschild radius, [itex]R[/itex].

    [tex] R = \frac{2 G m}{c^2} [/tex]

    The factor

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

    is a very small number.
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