Question

1. A box emits particles in a spin state | ψ〉. If we send these particles for an experiment Stern - Gerlach (see book or class notes) such that cos (θ/2) = 3/5 and sin (θ/2) = 4/5, we found that 16/25 of the particles have S_ϴ = + ħ/2
   1. If we assume that the components of | ψ〉 are real, show that there are two different vectors that are consistent with this result.
   2. If we now pass the particles emitted by the box through a Stern - Gerlach x, we find 77% of the particles come out with S_X = + ħ/2. Determine | ψ〉

Answer 1