- #1
nomadreid
Gold Member
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If we measure one conjugate variable in an uncertainty relation precisely , i.e., so its standard deviation is zero, then by the HUP the sd of the other one is either infinite or undefined. But what about the cases when the other conjugate variable has limits: e.g., there cannot be an infinite spread for momentum or energy? Is it then better to just say that the spread is undefined in this case?