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question on spin on nucleons (1 Viewer)
- Thread starter angmor
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Rohanesburg
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Spin is a phenomenon based on Pauli’s exclusion principle. The stability of the atomic structure due to spin, is purely a mathematical descripition based on heisenburg's uncertainty principle. And as a consequence there is no actual 'spin' of the nucleons, it is just a mathematical description of atomic structure.
I'm no expert in spin of nucleons, but as far as the spin of electrons go, they do "spin" in a sense... which is why unpaired electron carries a magnetic moment.
If I recall correctly, Pauli's exclusion principle is one used to describe electron configuration. As such, spin is definitely a observable phenomenon.
If I recall correctly, Pauli's exclusion principle is one used to describe electron configuration. As such, spin is definitely a observable phenomenon.
darkchild69
Nanotechnologist
I believe it is to do with the net orbital angular momentum equalling zero
zagga20
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Ok so yeah, this is a bit late for you... but for those of us who are still interested.
From what i read in Stephen Hawking's, A Brief History of Time.
Spin is a description of a particle.
Particles with Spin 0, are particles that are viewed the same, no matter how you rotate it.
such as a circle, or a dot.
Particles with spin 1, need to be rotated 360 degrees until they can be viewed in the same state.
such as an arrow -->
spin 2, need to be spun 180 degrees.
eg. <-->
and spin 1/2 must be spun 720 degrees until they can be viewed in the same state
eg... i...dont...know...
I believe this is just a description of their angular momentum though, because they dont physically spin, they just HAVE angular momentum.
either that, or i misread what good ol' hawking was trying to say. which is entirely possible!
From what i read in Stephen Hawking's, A Brief History of Time.
Spin is a description of a particle.
Particles with Spin 0, are particles that are viewed the same, no matter how you rotate it.
such as a circle, or a dot.
Particles with spin 1, need to be rotated 360 degrees until they can be viewed in the same state.
such as an arrow -->
spin 2, need to be spun 180 degrees.
eg. <-->
and spin 1/2 must be spun 720 degrees until they can be viewed in the same state
eg... i...dont...know...
I believe this is just a description of their angular momentum though, because they dont physically spin, they just HAVE angular momentum.
either that, or i misread what good ol' hawking was trying to say. which is entirely possible!
willC
New Member
Yes, as far as I can tell spin isn't actually an observable property, it's a description of how it's angular momentum behaves mathematically. The whole concept of a point mass being able to spin is absurd-it has no axis on which it can rotate! Hence why its called "intrinsic spin"
1/2 spin particles are particularly unusual-like zagga said. It takes two complete 'rotations' before they look the same as they did before rotating. This behaviour cannot be likened to any tangible object as most objects (for example cards, which Hawkings uses as a good analogy) look the same after either 1 or less complete rotations.
It's a real pity theres no syllabus dot point on spin 'cause, not only is it really interesting, but its one of the fundamental ideas of quantum physcis along with quantisation of angular momentum of electrons and the wave-particle duality.
Can't wait till physics tomorrow!!!!!!!!!!!!!!!
1/2 spin particles are particularly unusual-like zagga said. It takes two complete 'rotations' before they look the same as they did before rotating. This behaviour cannot be likened to any tangible object as most objects (for example cards, which Hawkings uses as a good analogy) look the same after either 1 or less complete rotations.
It's a real pity theres no syllabus dot point on spin 'cause, not only is it really interesting, but its one of the fundamental ideas of quantum physcis along with quantisation of angular momentum of electrons and the wave-particle duality.
Can't wait till physics tomorrow!!!!!!!!!!!!!!!