Cheng H.-CDatta NRouze C.HAO-CHUNG CHENG2021-09-022021-09-02202021578095https://www.scopus.com/inward/record.uri?eid=2-s2.0-85090424902&doi=10.1109%2fISIT44484.2020.9174427&partnerID=40&md5=edb6185d77aa2ac25f095e44ff3e23bdhttps://scholars.lib.ntu.edu.tw/handle/123456789/580538We develop the first method for finding strong converse bounds in quantum network information theory. The general scheme relies on a recently obtained result in the field of non-commutative functional inequalities, namely the tensorization property of quantum reverse hypercontractivity for the quantum depolarizing semigroup, and properties of the projectively measured R?nyi relative entropies. We develop a novel technique to employ this result to find both finite blocklength and exponential strong converse bounds for the tasks of distributed quantum hypothesis testing with communication constraints for a classical-quantum state, quantum source coding with compressed classical side information, and classical-quantum degraded broadcast channel coding. A full version of this paper is accessible at: arXiv:1905.00873 and arXiv:1905.00874. ? 2020 IEEE.Information theory; Classical-quantum; Communication constraints; Degraded broadcast channel; Functional inequalities; Novel techniques; Quantum hypothesis; Relative entropy; Side information; Quantum theoryconference paper10.1109/ISIT44484.2020.91744272-s2.0-85090424902