2011/07/05 by Vaibhav Madhok, Animesh Datta, Madhok, Vaibhav +1
Computer Science · Engineering · #FOS: Physical sciences #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Physics (quant-ph) #Wireless Communication Security Techniques
paper · pdf · doi:10.48550/arxiv.1107.0994
openalex publication_date 2011/07/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Positivity of quantum discord is shown to be equivalent to the strong sub additivity of the Von-Nuemann entropy. This leads to a connection between the mother protocol of quantum information theory [A. Abeyesinghe, I. Devetak, P. Hayden, and A. Winter, Proc. R. Soc. A 465, 2537, (2009)] and quantum discord. We exploit this to show that quantum discord is a measure coherence in the performance of the mother protocol. Since the mother protocol is a unification of an important class of problems (those that are bipartite, unidirectional and memoryless), we show quantum discord to be a measure of coherence in these protocols. Our work generalizes an earlier operational interpretation of quantum discord provided in terms of quantum state merging [V. Madhok and A. Datta, Phys. Rev. A 83, 032323, (2011)].