Krickis Sandkasten
| ψ ⟩ = α | ↓ ⟩ + β | ↑ ⟩ {\displaystyle |\psi \rangle =\alpha |\downarrow \rangle +\beta |\uparrow \rangle }
u = 1 N ( N − 1 ) ∑ j = 1 N ( v j − v m ) 2 {\displaystyle u={\frac {1}{N(N-1)}}\sum _{j=1}^{N}(v_{j}-v_{m})^{2}}
