Entanglement measures and the Hilbert-Schmidt distance

Ozawa, M

Published Jan 1, 2000• 121 citations

Abstract

In order to construct a measure of entanglement on the basis of a``distance'' between two states, it is one of desirable properties that the``distance'' is nonincreasing under every completely positive trace preservingmap. Contrary to a recent claim, this letter shows that the Hilbert-Schmidtdistance does not have this property.

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