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MathGroup Archive 2006

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Re: near Planck's mass

  • To: mathgroup at
  • Subject: [mg68459] Re: near Planck's mass
  • From: Roger Bagula <rlbagula at>
  • Date: Sun, 6 Aug 2006 02:56:29 -0400 (EDT)
  • References: <eb1jsc$e8b$>
  • Sender: owner-wri-mathgroup at

Another way to get it this kind of mass with a Sqrt[2] factor instead of 

(* Schwartzschild's singularity radius*)
(*with electronmagnetiic radius*)

This method is more like the Planck derivation at r=h/(m*c)
Roger Bagula wrote:

>Back about 1987 or before
> I was studying gravitation and quantum mechanics
>and I came across  this:
>(* Classical electromagnetic radius*)
>r = e^2/(m*c^2)
>(* Riemannian Curvature*)
>R = -2/r^2
>(* 3 space volume*)
>V = (4*Pi/3)*r^3
>(*scalar energy densidty*)
>T = m*c^2/V
>(* solution for R = -8Pi*G*T(v, v) : scalar reduction of Einstein's
>        general relativity*)
>Solve[R + (8*Pi*G/c^4)*T == 0, m]
>e = 4.80325*10^(-10)
>G = 6.6732*10^(-8)
>(* mass in grams*)
>m = e/Sqrt[3*G]
>At the time I hadn't run into Planck's mass.
>If you put in
> r=h/(m*c)
>in this calculation  you get a version of the Planck mass.
>I was wondering if this was a well known calculation like Planck's mass?

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