Alonzo Church
Mathematician & Logician
關於
Alonzo Church (1903–1995) was an American mathematician and logician who, working at Princeton, gave one of the two foundational definitions of computation. His lambda calculus captured the notion of an effectively calculable function through pure symbol substitution, and in 1936 he proved that the Entscheidungsproblem — Hilbert's dream of a general decision procedure for mathematics — has no solution. That same year, independently, Alan Turing reached the same boundary with his imaginary machines; their equivalence became the Church–Turing thesis, the bedrock claim about what computation is. Turing came to Princeton as Church's doctoral student. Church later held the Flint Professorship at UCLA (1967–1990).
主要貢獻
- Created the lambda calculus, a foundational model of computation still central to computer science
- Proved the undecidability of the Entscheidungsproblem (1936), independently of Turing
- Co-originated the Church–Turing thesis on the limits of effective computation
- Supervised Alan Turing's doctoral work at Princeton
- Founded the Journal of Symbolic Logic and shaped modern mathematical logic
