- #1
TheAtheistKing
We set speed v=0 all the time in physics, and reach neat and tidy conclusions, but can anything really be at rest? I am interested in criticisms to the following line of reasoning:
Definition of momentum
[tex] \vec P = mass*velocity = M \vec v [/tex]
And from this it follows that the magnitude of the momentum of a particle is equal to the particle's mass times the particle's speed.
In quantum mechanics the magnitude of the momentum of a particle is equal to Planck's constant divided by the wavelength of the particle.
[tex] |\vec P| = \frac{h}{\lambda} [/tex]
Hence we have:
[tex] m|\vec v| = \frac{h}{\lambda} [/tex]
So if something is at rest, then we have:
[tex] 0 = \frac{h}{\lambda} [/tex]
But nothing can really be infinite, so lambda cannot be infinite, hence the RHS must be nonzero. Hence if the fundamental relation of quantum mechanics is correct, then it follows that nothing can have speed |v|=0, hence no particle can be truly at rest.
Notice I have ignored the center of mass of bodies, but so focus on particles for now. Can any particle truly be at rest? If the above line of reasoning is fine, then wouldn't that mean that in any inertial reference frame whatsover, any particle is accelerating? And if that is the case, would this not explain why there was a second moment in time? And would this not explain why relative motion cannot cease?
Any thoughts?
Definition of momentum
[tex] \vec P = mass*velocity = M \vec v [/tex]
And from this it follows that the magnitude of the momentum of a particle is equal to the particle's mass times the particle's speed.
In quantum mechanics the magnitude of the momentum of a particle is equal to Planck's constant divided by the wavelength of the particle.
[tex] |\vec P| = \frac{h}{\lambda} [/tex]
Hence we have:
[tex] m|\vec v| = \frac{h}{\lambda} [/tex]
So if something is at rest, then we have:
[tex] 0 = \frac{h}{\lambda} [/tex]
But nothing can really be infinite, so lambda cannot be infinite, hence the RHS must be nonzero. Hence if the fundamental relation of quantum mechanics is correct, then it follows that nothing can have speed |v|=0, hence no particle can be truly at rest.
Notice I have ignored the center of mass of bodies, but so focus on particles for now. Can any particle truly be at rest? If the above line of reasoning is fine, then wouldn't that mean that in any inertial reference frame whatsover, any particle is accelerating? And if that is the case, would this not explain why there was a second moment in time? And would this not explain why relative motion cannot cease?
Any thoughts?
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