Consider two Hermitian operator A, B; Define(adsbygoogle = window.adsbygoogle || []).push({});

[A,B]=iC,

then operator C is also Hermitian.

we calculate the expectation value with respect to |a>, one eigenstate of A with the eigenvalue a.

From the left side, we have:

<a|[A,B]|a>=<a|(AB-BA)|a>=(a-a)<a|B|a>=0,

while on the right side, <a|iC|a> does not necessarily vanish.

That is :<a|[A,B]|a> ≠ <a|iC|a>, which is absurd !!!!!!

So what is wrong in my calculation?

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# Some inconsistency on operator expectation value

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