Armin Haken is a contemporary logician and computer scientist best known for his foundational work in proof complexity. His 1985 proof establishing an exponential lower bound on resolution proofs of the pigeonhole principle is a landmark result connecting logic, combinatorics, and computational complexity.
Proved the exponential lower bound for resolution proofs of the pigeonhole principle (1985)
Contributed foundational results to proof complexity theory
Bridged mathematical logic and computational complexity