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arXiv · quant-ph/0309177

Towards a geometrical interpretation of quantum information compression

Graeme Mitchison·Richard Jozsa
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Abstract

Let S be the von Neumann entropy of a finite ensemble E of pure quantum states. We show that S may be naturally viewed as a function of a set of geometrical volumes in Hilbert space defined by the states and that S is monotonically increasing in each of these variables. Since S is the Schumacher compression limit of E, this monotonicity property suggests a geometrical interpretation of the quantum redundancy involved in the compression process. It provides clarification of previous work in which it was shown that S may be increased while increasing the overlap of each pair of states in the ensemble. As a byproduct, our mathematical techniques also provide a new interpretation of the subentropy of E.

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Graeme Mitchison, Richard Jozsa. 2003-09-24. Towards a geometrical interpretation of quantum information compression. https://doi.org/10.1103/physreva.69.032304

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