4.5.1 Wave function for a single particle with spin

1

If you write the wave function of a particle with spin as a single function, what is its form?

2

What probability is given by that function?

3

If you write the wave function of a spin $\frac12$ fermion as a combination of purely spatial and purely spin functions, what is its form?

4

What probability is given by the function $\Psi_-$?