Natural Metric for Quantum Information Theory
P. W. LAMBERTI; M. PORTESI; J. SPARACINO
INTERNATIONAL JOURNAL OF QUANTUM INFORMATION
WORLD SCIENTIFIC PUBL CO PTE LTD
Lugar: Singapore; Año: 2009 p. 1009 - 1019
We propose a very natural metric between quantum states. This proposal has two basic ingredients: entropy and purification. The metric is defined as the square root of the entropy of the average of representative purifications of the concomitant mixed states. Some basic properties are studied and its relation with other distances is investigated.