Originating from
the Greek analogous hóper édei deîxai (ὅπερ ἔδει δεῖξαι), meaning "which had to be demonstrated". The phrase is traditionally placed in its abbreviated form (Q.E.D.) at the end of a
mathematical proof or
philosophical argument. Phrase synonymous with "Quite Easily Done."
∫|Ψ(x, t)|² dx (from -infinity to
infinity)= e^(2Γt/ħ) ∫|ψ|²dx(from -infinity to infinity)
The
second term is
independant of t, therefore Γ=0 & ∫|Ψ(x, t)|² dx (from -infinity to infinity)=∫|ψ|²dx(from -infinity to infinity)=1 {Normalized}
Q.E.D. "quod erat demonstrandum"