Spectra and variance of quantum random variables

JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS

卷:434

Article

Farenick, Douglas¹  Kozdron, Michael J.¹  Plosker, Sarah² 

[1] Univ Regina, Dept Math & Stat, Regina, SK S4S 0A2, Canada

[2] Brandon Univ, Dept Math & Comp Sci, Brandon, MB R7A 6A9, Canada

关键词: Positive operator-valued measure;    Quantum probability measure;    Quantum random variable;    Variance;    Quantum noise;    Smearing;   

DOI  :  10.1016/j.jmaa.2015.09.055

来源: Elsevier

【 摘 要 】

We study essentially bounded quantum random variables and show that the Gelfand spectrum of such a quantum random variable psi coincides with the hypoconvex hull of the essential range of psi. Moreover, a notion of operator-valued variance is introduced, leading to a formulation of the moment problem in the context of quantum probability spaces in terms of operator-theoretic properties involving semi invariant subspaces and spectral theory. As an application of quantum variance, new measures of random and inherent quantum noise are introduced for measurements of quantum systems, modifying some recent ideas of Polterovich [17]. (C) 2015 Elsevier Inc. All rights reserved.

【 授权许可】

Free