The AMMSI-Phillip Griffiths Prize for 2019 is awarded to Charles E. Chidume of the African University of Science and Technology in Abuja, Nigeria. Professor Chidume's work encompasses several fields, including Nonlinear Functional Analysis, Nonlinear Operator Theory and Differential Equations; in particular, his research focuses on the area of fixed point theory where his contributions have become indispensable. He is noted for his proof that the Mann sequence for non-expansive maps is uniformly asymptotically regular in any real normed space provided the domain of the map is bounded, hence resolving a problem which had been open since 1978. In another brief, elegant paper, he produced an example to show that the Mann iteration sequence will not always converge strongly to a fixed point of a Lipschitz pseudo-contractive map, thereby resolving an open problem in the field for several decades. He authored or co-authored over 183 research papers and his works have been extensively cited. Professor Chidume has received multiple prestigious awards, including the British Council Fellowship in Mathematics (1986), the Third World Academy of Sciences (1988), the Honor Certiﬁcate by the Romanian Mathematical Society (2018).
Professor Chidume has played a key role in discovering and developing young mathematicians in Africa through supervision of many postgraduate students at the International Center for Theoretical Physics (ICTP) in Trieste, Italy, and at the University of Nigeria, Nsukka. He has served as an Associate Editor of numerous scientific journals and is a Fellow of The World Academy of Sciences (FTWAS), among others.