Referrence to Modern Quantum Mechanics, J.J.Sakurai,(adsbygoogle = window.adsbygoogle || []).push({});

I found the "Generalized Uncertainty Principle" is that

<( s.d. of operator A)^2> <( s.d. of operator B)^2> >= 1/4 |<[A,B]>|^2 + 1/4 |<{s.d of A, s.d of B}>|^2

I hope it is not difficult to read, as I don't know how to type it formally.

I would like to ask why the inequality finally omitted the second (the anticommutator) term ?

Sakurai said it is because the second term can only make the inequality relation stronger.

I can't understand. Besides, I am a UG Year 1 students, but familiar to Dirac Notation as I am doing UG research on Quantum Information Theory. I hope any one can explain it in a easy way ^^ Thank You

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# Derivation of Uncertainty Princple

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