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Magnetic induction protons


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Hello everyone

 

I basically get the hang of MRI, but I'm left with one small - not all too important - question:

 

Although protons do not genuinly spin, creating their own cute little magnetic dipole, let's consider they do, for simplicity.

 

Does the right-hand rule apply to protons? Or electrons?

 

As in: consider a proton spinning in the plane of your computer screen, in a counterclockwise sense. Does the magnetic dipole inducted by its spin point out of your screen? Or inwards?

 

Is the contrary true for electrons? (Not important in MRI, but just curious; physics is a great while ago)

 

Thanks.

 

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I think - and this is very much guesswork - that quantum spin precession in a magnetic field follows exactly the same shape and direction path as would be expected by a classical spin precession in a magnetic field; thus nomenclature is the same. If you think about it, the direction of angular momentum vector is somewhat arbitrary - ie why we have a rule; it would strike me as strange that intrinsic angular momentum was classified differently. But, and it is a very big But, my answer is assumption rather than knowledge.

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Yes your correct the particle spin does follow the left hand/right rules

 

So the unity charge of the particle doesn't matter (+ or -), as long as it's charged? It's just for a figure in my thesis; I should know whether a counterclockwise spinning proton would have its magnetic field vector point inwards or outwards ... Conventionally seen

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For a thesis paper you want to apply Pati-Salam. Recall the only difference between a particle/antiparticle pair is charge.

 

The left hand right hand rules are incoroerated into your Pati-Salam symmetry groups.

 

Which follows chirality and helicity as applied to spin.

 

https://en.m.wikipedia.org/wiki/Chirality_(physics)

 

https://en.m.wikipedia.org/wiki/Helicity_(particle_physics)

 

Pati-Salam incorporates these two aspects under SO (10).

 

edit ignore chiral theory where its theorized a difference between the left/right hand. For the purpose of this thread its off topic. The general rules and formulas still applies.

Your proton spin magnetic dipole moment formulas can be found here.

 

https://en.m.wikipedia.org/wiki/Proton_magnetic_moment

Edited by Mordred
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