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Can the expectation value of the position x ever equal a finite value for which the...

Can the expectation value of the position x ever equal a finite value for which the probability function P(x) is zero? Give a specific example.
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Answer #1

Yes, the expectation value of position x can be non-zero for which the probability function P(x) is Zero.

There are many examples available for such kind of cases.

Example- According to the Ehrenfest Theorem for time-dependent problems of quantum mechanics- the expectation value of the position operators can be non-zero.

A time-dependent Harmonic oscillator and the time-dependent 1-D potential well problem can be an example of such a case.

Ehrenfest Theorem-

d/dt(<x>) = (1/m) <p>

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