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Author Topic: Particle Spin  (Read 3067 times)

Offline Supercryptid

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Particle Spin
« on: 18/12/2005 01:24:06 »
Particles are said to spin like tops, but this spin is quantized. So here are some questions regarding spin:

1) Can particles be thought of as spinning a certain number of times around their axis of rotation per minute, much as a wheel? That is, can the RPM of a particle's spin be calculated?

2) Do all particles of a particular type rotate at the same RPM? For example, do all electrons spin at the same speed, or do some rotate faster than others?


 

Offline Soul Surfer

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Re: Particle Spin
« Reply #1 on: 18/12/2005 18:20:11 »
"Spin" is quantised and all isolated electrons are essentially identical.

The spin of a particle is a bit more complex than that of a simple tennis or cricket ball it is really something to do with angular momentum and as particles cannot be localised properly thinking of it as RPM is not useful idea.  I am looking for some good web pages to explain spin and will post them later if I can find one.

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Offline gsmollin

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Re: Particle Spin
« Reply #2 on: 20/12/2005 12:42:39 »
Fundamental particles have duality properties. In some experiments, the spin of an electron appears to be about an axis, just like a tennis ball. In other experiments, it does not. This is similar to wave-particle duality, and electrons have that property too. Macroscopic analogies to fundamental properties are very tricky, and many phycisists don't use them because of that, so frequently good papers on QM lack this intuition.

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Offline Solvay_1927

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Re: Particle Spin
« Reply #3 on: 21/12/2005 23:08:44 »
quote:
I am looking for some good web pages to explain spin and will post them later if I can find one.

Ian, please do post some if you can find any - I'd like to understand "spin" better myself.  I can't find anything between the very technical (requiring a good understanding of quantum mathematics) and the very basic (descriptions which just say "it popped out of Dirac's application of special relativity to Schrodinger's equations" without explaining what that really means).
Ta.
Paul.
 

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Re: Particle Spin
« Reply #3 on: 21/12/2005 23:08:44 »

 

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