I am aware of the expectation value [tex]\left\langle\ r \right\rangle[/tex]. But I was wondering what is physically meant by the expectation value: [tex]\left\langle\frac{1}{r}\right\rangle[/tex](adsbygoogle = window.adsbygoogle || []).push({});

The reason I am asking is because calculating this (reciprocal) expectation value for the 1s state of hydrogen, one obtains [tex]1/a_{o}[/tex]

This result happens to be the reciprocal of the most probable value of r for the 1s state of hydrogen. [but expectation values gives the mean value of the quantity working on, so there must be a coincidence occurring here]. I hope someone can enlighten me here.

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# The reciprocal expectation value

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