Conditional Entropy and Information in Quantum Systems

✍ Scribed by L.B. Levitin

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 235 KB
• Volume: 10
• Category: Article
• ISSN: 0960-0779
• DOI: 10.1016/s0960-0779(98)00225-2

✦ Synopsis

The concepts of conditional entropy of a physical system given the state of another system and of information in a physical system about another one are generalized for quantum systems[ The fundamental di}erence between the classical case and the quantum one is that the entropy and information in quantum systems depend on the choice of measurements performed over the systems[ It is shown that some equalities of the classical information theory turn into inequalities for the generalized quantities[ Speci_c quantum phenomena such as EPR pairs and {superdense coding| are described and explained in terms of the generalized conditional entropy and information[