Sorry if this question is very general/vague, but I would prefer a general answer rather than a specific solution... I'll put more detail in if necessary though.(adsbygoogle = window.adsbygoogle || []).push({});

So, say we have a Hamiltonian for a system (of fermions, spin 1/2); then we find its eigenvalues and hence eigenstates. These are then energy eigenstates, yes? What I really need is the spin states; how do I get them?

The only infomation I have, other than the Hamiltonian, is that the spin 1/2 particles are described by the Dirac equation (2D).

I'm thinking pauli spin matrices might be useful here?

Obviously, you get (0,1) and (1,0) {column not row vectors there obviously) for spin up and spin down; but I think I need some kind or linear combination of these?

Sorry if it's not clear, I'm a bit out of my depth here!

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# Homework Help: Hamiltonian and spin states

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