We all know the concept of expectation value,it is the average of all possible outcomes of an experiment. Mathematically average of x is written as (Σnkxk / Σnk ). Quantum-mechanically nk is represented by probability density(P), where P = ∫Ψ*Ψ d3r,(adsbygoogle = window.adsbygoogle || []).push({});

then <r> = ∫ r P(r) d3r -----------(1)

or <r> = ∫ Ψ*(r) r Ψ(r) d3r--------(2) (normalisation condition)

but when we consider expectation value of Energy operator (= ih∂/∂t) the two equations ,to me, not give the same results. Can anybody solve what’s that dilemma and where I am wrong

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# Expectation Value

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