| Citation | Plotkin has contributed to Artificial Intelligence, Logic, Linguistics and especially to Computer Science. In AI he worked on hypothesis-formation and universal unification; in Logic, on frameworks for arbitrary logics; in Linguistics, on formalising Situation Theory.
His main general contribution has been to establish a semantic framework for Computer Science, especially programming languages. Particular significant results are in the lambda-calculus (elementary models, definability, call-by-value), non-determinism (powerdomain theory), semantic formalisms (structured operational semantics, metalanguages), and categories of semantic domains (coherent, pro-finite, concrete). Further contributions concern the semantic paradigm of full abstraction, concurrency theory (event structures), programming logic and type theory. |