Abstract
We introduce a measure of compatibility between quantum states—the likelihood that two density matrices describe the same object. Our measure is motivated by two elementary requirements, which lead to a natural definition. We list some properties of this measure, and discuss its relation to the problem of combining two observers’ states of knowledge.
- Received 16 May 2002
DOI:https://doi.org/10.1103/PhysRevA.67.010101
©2003 American Physical Society
