Momentum uncertainty
= Momentum uncertainty
{title2=$\Delta p=\sqrt{\langle\hat p^2\rangle-\langle\hat p\rangle^2}$}
The <standard deviation> of the <momentum> measurement distribution of a <quantum state>. A zero mean momentum need not imply zero momentum uncertainty. For a normalized state with finite moments, position and momentum uncertainties obey the <Heisenberg uncertainty relation>.