Quantum Reports

Higher-Order Information Measures from Cumulative Densities in Continuous Variable Quantum Systems

Saúl J. C. Salazar, Humberto G. Laguna, Robin P. Sagar

Published Nov 6, 2020• 4 citations

Abstract

A definition of three-variable cumulative residual entropy is introduced, and then used to obtain expressions for higher order or triple-wise correlation measures, that are based on cumulative residual densities. These information measures are calculated in continuous variable quantum systems comprised of three oscillators, and their behaviour compared to the analogous measures from Shannon information theory. There is an overall consistency in the behaviour of the newly introduced measures as compared to the Shannon ones. There are, however, differences in interpretation, in the case of three uncoupled oscillators, where the correlation is due to wave function symmetry. In interacting systems, the cumulative based measures are shown in order to detect salient features, which are also present in the Shannon based ones.

DOI: 10.3390/quantum2040039

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