Spin - any book recommendations?

[Truecrimson]

If your aim is to learn by examples and problems, you might want to take a look at Zettili.

 

[dextercioby]

why should I waste my valuable time to preach from the R-QM textbooks? I have already said that intrinsic angular momentum (called spin) is a manifestation due to Lorentz Symmetry: Which we have pretty good proofs that this symmetry is realized in nature.

All particles have intrinsic angular momentum; fermions have 1/2, i.e. transform under the irreducible representation of the Lorentz group. Scalars have 0, i.e. transforms as singlets. Vectors are particles that transforms as four-vectors, tensor-2 particles are particles that transforms as rank-2 tensors etc etc.

So compact: Intrinsic Angular momentum / spin is a symmetry manifestation.

Analogy: electric charge is a symmetry manifestation of the gauge transformations in electromagnetism.

Physics is about symmetries, once you know the symmetries in nature, we can deduce the dymanics.

As far as I know, you don't need to include the special relativity into quantum mechanics in order to to "derive" the concept of spin. You can do that very well with a Newtonian "background".

 

[dextercioby]

Spin is not a relativistic property. The existence of the spin operators can be derived from the assumption that space is rotationally invariant.

I think you're wrong. Spin cannot be "derived" (it's rather <introduced>) without the assumption of <relativity>, be it special/Minkowski or Galilean.

 

[Fredrik]

I think you're wrong. Spin cannot be "derived" (it's rather <introduced>) without the assumption of <relativity>, be it special/Minkowski or Galilean.

You can take the existence of the spin operators to be an axiom if you prefer, but that doesn't make what I said wrong. What is it that you think I'm wrong about?

 

[dextercioby]

I didn't mention <axioms> in any place. I just asserted that there's no discussion of spin, unless one brings in relativity in quantum mechanics. So i'd say that spin is a relativistic property (flat spacetime), just like mass.

 

[Fredrik]

OK, I misunderstood what you were trying to say. I get it now. You can certainly derive the existence of spin from the axiom I used. If we replace the rotation group in my argument with the Galilei group (i.e. if we consider the principles of QM combined with Galilean relativity), we get a lot more, including momentum, energy and mass operators, and the Schrödinger equation.