Jan Willem Klop was a distinguished scientist renowned for his foundational work in various aspects of the theory of computation.
Thanks to his efforts in 2003 a multi-authored 900-page book, 'Term Rewriting Systems,' appeared, of which he was the main author. The book's review in the Journal of Functional Programming noted that it is 'a compulsory reference for anyone working in the area.' Jan Willem also collaborated with Prof. dr. J.A. (Jan) Bergstra and Prof. dr. J.C.M. (Jos) Baeten on the development of process algebra (ACP, Algebra of Communicating Processes). In 2007 he retired early to fully devote his time to research. His last publication appeared in 2021. Until the last moment he pursued his plans for writing books that would emphasize the beauty of term rewriting and lambda calculus.
Career in a nutshell
Jan Willem Klop was born in 1945 in Gorinchem. He studied mathematical logic at Utrecht University, where he graduated obtaining his Master degree (cum laude) in 1975. In 1980 he defended his PhD thesis ‘Combinatory Reduction Systems’ there, supervised by Professors Dirk van Dalen and Henk Barendregt. From 1979 to 1980, he taught mathematics at the teachers training institute SOL (Stichting Opleiding Leraren) in Utrecht. Since 1986 until his retirement he was part-time Professor at the Vrije Universiteit (VU) Amsterdam, and from 1998 until 2007 also part-time Professor at the Radboud University Nijmegen. From 1999 to 2004, Jan Willem served as head of the section Theoretical Computer Science at the VU. For the last two years of that period, he headed its Department of Computer Science. From 1998 until 2004 he was chairman of the Dutch Association for Theoretical Computer Science (NVTI). In 2002 Jan Willem received an honorary doctorate at the University of East Anglia, England. Since 2003 he was a member of the Royal Dutch Academy of Sciences (KNAW), section Mathematics. In 2010 he became a member of the Informatics Section of the Academia Europaea and a honorary member of the IFIP Working group 1.6 Rewriting.
Jan Willem was an inspiring and leading scientist who not only left an indelible mark on his field but also on CWI. We will remember him as a very kind, warm, and involved person who mentored a large number of PhD students. He was also an excellent teacher, renowned for his inspiring lectures and extensive survey papers that were highly appreciated by his colleagues in the Netherlands and abroad.
We extend our deepest condolences to his family, friends, and loved ones on their profound loss.
