Abstract
We characterize all coexistent pairs of qubit effects. This gives an exhaustive description of all pairs of events allowed, in principle, to occur in a single qubit measurement. The characterization consists of three disjoint conditions, which are easy to check for a given pair of effects. Known special cases are shown to follow from our general characterization theorem.
- Received 23 April 2008
DOI:https://doi.org/10.1103/PhysRevA.78.012315
©2008 American Physical Society