arXiv:1711.04037 · Physical Review A

Variance uncertainty relations without covariances for three and four observables

V. V. Dodonov

Published Feb 7, 2018• 30 citations

Abstract

Sum and product uncertainty relations, containing variances of three or four observables, but not containing explicitly their covariances, are derived. Their consequences are, in particular, inequalities, giving nonzero lower bounds for the products of two variances in the case of zero mean value of the commutator between the related operators. Explicit examples show that the bounds can be better than the known Robertson-Schr\"odinger one.

DOI: 10.1103/physreva.97.022105

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