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Physical Review Letters

Statistical distance and the geometry of quantum states

Samuel L. Braunstein, Carlton M. Caves

Published May 30, 1994• 3,176 citations
Publisher

Abstract

By finding measurements that optimally resolve neighboring quantum states, we use statistical distinguishability to define a natural Riemannian metric on the space of quantum-mechanical density operators and to formulate uncertainty principles that are more general and more stringent than standard uncertainty principles.
DOI
10.1103/physrevlett.72.3439

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