Wave interference
Quantum interference

Usually, Ψ A (x, t) {\displaystyle \Psi _{A}(x,t)} and Ψ B (x, t) {\displaystyle \Psi _{B}(x,t)} correspond to distinct situations A and B. When this is the case, the equation Ψ (x, t) = Ψ A (x, t) + Ψ B (x, t) {\displaystyle \Psi (x,t)=\Psi _{A}(x,t)+\Psi _{B}(x,t)} indicates that the object can be in situation A or situation B. The above equation can then be interpreted as: The probability of finding the object at x {\displaystyle x} is the probability of finding the object at x {\displaystyle x} when it is in situation A plus the probability of finding the object at x {\displaystyle x} when it is in situation B plus an extra term. This extra term, which is called the quantum interference term, is Ψ A ∗ (x, t) Ψ B (x, t) + Ψ A (x, t) Ψ B ∗ (x, t) {\displaystyle \Psi _{A}^{*}(x,t)\Psi _{B}(x,t)+\Psi _{A}(x,t)\Psi _{B}^{*}(x,t)} in the above equation. As in the classical wave case above, the quantum interference term can add (constructive interference) or subtract (destructive interference) from | Ψ A (x, t) | 2 + | Ψ B (x, t) | 2 {\displaystyle |\Psi _{A}(x,t)|^{2}+|\Psi _{B}(x,t)|^{2}} in the above equation depending on whether the quantum interference term is positive or negative. If this term is absent for all x {\displaystyle x}, then there is no quantum mechanical interference associated with situations A and B.
punctuation:no_comma, oulipo:avoid_letter[a]