- #1
dyn
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Hi
For 2 Hermitian operators A and B using the Cauchy-Schwarz inequality and assuming the expectation values of A and B are zero I get
(ΔA)2(ΔB)2 ≥ (1/4)|<(AB+BA)>|2 + (1/4)|<(AB-BA)>|2
Now both terms on the RHS are positive so why is this inequality usually just written with only the commutator term , dropping the anti-commutator term ? Surely it could be written with only the 1st term instead ? And why is it not normally written with both terms ?
Thanks
For 2 Hermitian operators A and B using the Cauchy-Schwarz inequality and assuming the expectation values of A and B are zero I get
(ΔA)2(ΔB)2 ≥ (1/4)|<(AB+BA)>|2 + (1/4)|<(AB-BA)>|2
Now both terms on the RHS are positive so why is this inequality usually just written with only the commutator term , dropping the anti-commutator term ? Surely it could be written with only the 1st term instead ? And why is it not normally written with both terms ?
Thanks