Preparational Uncertainty Relations for N Continuous Variables

A smooth function of the second moments of N continuous variables gives rise to an uncertainty relation if it is bounded from below. We present a method to systematically derive such bounds by generalizing an approach applied previously to a single continuous variable. New uncertainty relations are...

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Bibliographic Details
Main Authors: Spiros Kechrimparis, Stefan Weigert
Format: Article
Language:English
Published: MDPI AG 2016-07-01
Series:Mathematics
Subjects:
Online Access:http://www.mdpi.com/2227-7390/4/3/49
Description
Summary:A smooth function of the second moments of N continuous variables gives rise to an uncertainty relation if it is bounded from below. We present a method to systematically derive such bounds by generalizing an approach applied previously to a single continuous variable. New uncertainty relations are obtained for multi-partite systems that allow one to distinguish entangled from separable states. We also investigate the geometry of the “uncertainty region” in the N ( 2 N + 1 ) -dimensional space of moments. It is shown to be a convex set, and the points on its boundary are found to be in one-to-one correspondence with pure Gaussian states of minimal uncertainty. For a single degree of freedom, the boundary can be visualized as one sheet of a “Lorentz-invariant” hyperboloid in the three-dimensional space of second moments.
ISSN:2227-7390