More explicitly, the superposition principle (ψ = Σ n a n ψ n) of quantum physics dictates that for a wave function ψ, a measurement will result in a state of the quantum system of one of the m possible eigenvalues f n , n = 1, 2,..., m, of the operator ∧ F which in the space of the eigenfunctions ψ n , n = 1, 2,..., m.