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So my question is how likely is this scenerio.

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- Thread starter Kt_Atis
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- #1

- 18

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So my question is how likely is this scenerio.

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So my question is how likely is this scenerio.

the thing that bothers me about the concept of the weakness of gravity is that when you get to specifics, it isn't only a comparison of the force of gravity to the forces of other fundamental interactions, say electromagnetic, but there are other quantities involved like the amounts of mass and charge. and these quantities are not commensurable ("comparing apples to oranges"), so since the force of gravity depends on how much mass you have and the force of E&M depends on how much charge you have, who says that gravity as a class of interaction is weaker than EM as an interaction? we can come up with a mass-to-charge ratio where the forces would be equal.

[tex] \sqrt{ \frac{1}{G 4 \pi \epsilon_0} } = \frac{m_P }{q_P} [/tex]

with a mass/charge ratio of that, the strength of gravity is the same as the strength of EM. but elementary particles have a much less mass/charge ratio than that. so that is why, for charged elementary particles, the gravitational interaction seems to be insignificant - because the charge on the protons is approximately the Planck unit of charge but the mass of the protons is far, far less than the Planck mass.

i like how Frank Wilczek puts it:

http://www.physicstoday.org/pt/vol-54/iss-6/p12.html [Broken] June 2001 Physics Today...We see that the question [posed] is not, "Why is gravity so feeble?" but rather, "Why is the proton's mass so small?" For in Natural (Planck) Units, the strength of gravity simply is what it is, a primary quantity, while the proton's mass is the tiny number [1/(13 quintillion)]...

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