In Memory of Professor Ming-Chit LIU

With great sorrow, we lament the passing of our esteemed former Chair Professor, Ming-Chit LIU (廖明哲), who departed from this world on 24^th March 2023 at the age of 85. He is survived by his wife Ms Moon-Chi CHEUNG and two sons Kay-Wai LIU and Yun-Wai LIU.

Professor Liu dedicated more than thirty years of his life to The University of Hong Kong (HKU). After obtaining his BSc (Special) from the University in 1966, he joined the Department of Mathematics at HKU as a demonstrator. Simultaneously, he pursued his Master of Science degree under the guidance of Professor Yung-Ming CHEN. After completing his doctoral degree, Professor Liu was promoted to Lecturer in 1973 and continued his career at HKU. He was later promoted to Reader in 1983 and then to Professor in 1990. During his tenure, Professor Liu shifted his research interests from complex analysis to analytic number theory, particularly focusing on Diophantine equations and Diophantine inequalities involving prime numbers. His research on the well-known Goldbach conjecture set a new record in this challenging problem of number theory in 2002. He made significant contributions to strengthen the connections between the Department and external academic institutions.

Professor Liu taught first-year calculus for many years, delivering clear and well-organised lectures. Many students were fortunate to learn how to read and write epsilon-delta proofs from him. He also taught courses in number theory and postgraduate complex analysis, providing rigorous training in analytic number theory. In addition to serving on various departmental and university committees at HKU, Professor Liu also served on various review and selection committees for several local universities and the Hong Kong Government. For example, he served as Vice-President of the Hong Kong Mathematical Society from 1996 to 1998.

Professor Liu retired from HKU in 2000, and in 2005, the Department of Mathematics established the Liu Ming-Chit Prize in Mathematics with his generous donation. Currently, a team of five people working on number theory or closely related areas is maintained by the department.

Professor Liu will be dearly missed by the University and the Faculty of Science family. A full obituary of him by Professors Yuk Kam LAU and Patrick, Tuen Wai NG from Department of Mathematics can be viewed at: https://hkumath.hku.hk/web/memory/memory_mcliu_main.php