Prof. Qi Chen
Xidian University, China
Date : 15 July 2026 (Wednesday)
Time : 11:00am – 12:00nn
Venue : Rm 804, William M.W. Mong Engineering Building, CUHK
Abstract:
Characterization of the entropy region is a fundamentally important but difficult information theoretic problem. When the number of random variables exceeds 3, the corresponding entropy region is not Shannon-tight; that is, Shannon-type information inequalities cannot fully characterize its closure. In our work, we project the region into subspaces of the entropy space corresponding to symmetric constraints induced by permutation groups, and determine whether the resulting regions are Shannon-tight or not. The Shannon-tightness of symmetric entropy regions induced by all permutation groups is determined, with exceptions for some almost simple-type groups and intransitive groups.
Biography:
Qi Chen received his PhD from the Information Engineering Department at The Chinese University of Hong Kong in 2014. From 2014 to 2017, he was a postdoctoral fellow at the Institute of Network Coding and the Information Engineering Department, The Chinese University of Hong Kong. From Sept. 2015 to Jan. 2016, he was also a postdoctoral researcher in the ECE department at Drexel University. In 2018, he joined the School of Telecommunications Engineering, Xidian University, Xi’an, China, where he is now an associate professor. His research interests include information theory and related areas, in particular, the characterization of the entropy region.
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