I am a professor in the Department of Information Engineering at the Chinese University of Hong Kong. My research interests and contributions focus on developing ideas, tools, and techniques to address families of combinatorial and non-convex optimization problems, primarily arising in the information sciences.
Since 2007, my work has been broadly motivated by the study of the optimality and sub-optimality of achievable regions in multi-user information theory—specifically, Marton’s achievable region for the two-receiver broadcast channel and the Han–Kobayashi achievable region for the two-sender, two-receiver interference channel.
Research interests
My recent research revolves around deriving new families of information inequalities, particularly those exhibiting sub-additivity or additive structure, and understanding extremizers of associated non-convex optimization problems.
- Network information theory, especially broadcast and interference channels.
- Information inequalities, hypercontractivity, and strong data processing.
- Additive combinatorics and its connections to entropy and mutual information.
- Random structures in statistical physics and combinatorial optimization.
Selected recent work
- Information Inequalities via Ideas from Additive Combinatorics.
K. Lau and C. Nair. ISIT 2023. [pdf] - An Extension of the Unified Brascamp–Lieb and the Entropy Power
Inequality to Finite Abelian Groups.
K. Lau and C. Nair. ISIT 2024; journal version to appear in Festschrift for Andrew Barron. [pdf] - A Differential Equation Approach to the Most-Informative Boolean
Function Conjecture.
Z. Chen, A. Gohari, and C. Nair. ISIT 2025. [pdf] - Outer Bounds for Multiuser Settings: The Auxiliary Receiver Approach.
A. Gohari and C. Nair. IEEE Trans. IT, vol. 68, pp. 701–736, 2022. [pdf] - The Capacity Region for Classes of Sum-Broadcast Channels.
A. Gohari, Y. Liu, and C. Nair. Manuscript, January 2026. [pdf]
A summary of my research is available in my research summary, and a full list of papers is on the publications page.
Teaching (recent)
- Multiuser information theory (most recent: Spring 2025)
- Signals and systems (most recent: Fall 2025)
- Probability theory [graduate] (most recent: Spring 2026)
For prospective students
I supervise PhD, MPhil, and undergraduate projects at the intersection of information theory, probability, and combinatorics. A solid background in analysis and probability is important; familiarity with information theory is helpful but not essential.
If you are interested in working with me, please email a brief CV, your main mathematical interests, and relevant coursework or projects. CUHK MIEG students are welcome to visit my office to discuss possible topics.
Contact
Room 811, Ho Sin Hang Engineering Building
Department of Information Engineering
The Chinese University of Hong Kong
Shatin, New Territories, Hong Kong
Email: cnair@ie.cuhk.edu.hk
Additional information: short resume, department profile.