Let A be an observable (opeator), and we're assuming that for a given state psi(x), the value of A is given by A acting on psi(x), namely - A|psi>.(adsbygoogle = window.adsbygoogle || []).push({});

Also we assume that - P(x) = |psi(x)|^2

So, I'de expect the Expectation value of A to be defined like so:

<A> = Integral[-Inf:+Inf]{ P(x) A psi(x) dx} = Integral[-Inf:+Inf]{ |psi(x)|^2 A psi(x) dx} , which is not <psi|A|psi>, and that's clearly not right. where did i go wrong here?

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# Calculating expectation value

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