General quantum measurements are represented by instruments. In this paper the mathematical formalization is given of the idea that an instrument is a channel which accepts a quantum state as input and produces a probability and an a posteriori state as output. Then, by using mutual entropies on von Neumann algebras and the identification of instruments and channels, many old and new informational inequalities are obtained in a unified manner. Such inequalities involve various quantities which characterize the performances of the instrument under study; in particular, these inequalities include and generalize the famous Holevo's bound.
Instruments and mutual entropies in quantum information / A. Barchielli, G. Lupieri - In: Quantum probability / [a cura di] Marek Bożejko, Wojciech Młotkowski, Janusz Wysoczański. - Warszawa : Instytut Matematyczny PAN, 2006. - pp. 65-80 (( Intervento presentato al 25. convegno QP Conference on quantum probability and related topics tenutosi a Będlewo, Poland nel 2004.
Instruments and mutual entropies in quantum information
G. LupieriUltimo
2006
Abstract
General quantum measurements are represented by instruments. In this paper the mathematical formalization is given of the idea that an instrument is a channel which accepts a quantum state as input and produces a probability and an a posteriori state as output. Then, by using mutual entropies on von Neumann algebras and the identification of instruments and channels, many old and new informational inequalities are obtained in a unified manner. Such inequalities involve various quantities which characterize the performances of the instrument under study; in particular, these inequalities include and generalize the famous Holevo's bound.
Pubblicazioni consigliate
I metadati presenti in AIR sono rilasciati con licenza CCO mentre i file delle pubblicazioni sono rilasciati con licenza CC BY-SA, salvo diversa indicazione. In caso di violazione di copyright, contattare l'assistenza di AIR
