Coexistence of qubit effects
نویسندگان
چکیده
Two quantum events, represented by positive operators (effects), are coexistent if they can occur as possible outcomes in a single measurement scheme. Equivalently, the corresponding effects are coexistent if and only if they are contained in the ranges of a single (joint) observable. Here we give a necessary and sufficient condition for the coexistence of a pair of qubit effects.
منابع مشابه
Coexistence of Qubit Effects
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.
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عنوان ژورنال:
- Quantum Information Processing
دوره 9 شماره
صفحات -
تاریخ انتشار 2010