Operationally invariant measure of the distance between quantum states by complementary measurements.
We propose an operational measure of distance of two quantum states, which conversely tells us their closeness. This is defined as a sum of differences in partial knowledge over a complete set of mutually complementary measurements for the two states. It is shown that the measure is operationally invariant and it is equivalent to the Hilbert-Schmidt distance. The operational measure of distance provides a remarkable interpretation of the information distance between quantum states.
Lee
Jinhyoung
J
School of Mathematics and Physics, The Queen's University, Belfast BT7 1NN, Northern Ireland, UK. jlee@am.qub.ac.uk
Kim
M S
MS
Brukner
Caslav
C