It is not clear what complex wave function means in Schrödinger, Pauli, Dirac equations. Is it always two-component (complex), or can it be real, or are both variants possible in different situations?
For example, how to understand:
-i · h/(2·π) · ∂ψ/∂t = h2/(8·π2·m) · div grad ψ
(for simplicity in absence of potential multiplied by function).
The imaginary unit “i” simply shows that quantum operator is used instead of classical derivative, or function must be divided into tw