The complexity of the equivalence problem for counter machines, semilinear sets, and simple programs. Some connections between mathematical logic and complexity theory. A completeness technique for D -axiomatizable semantics. Michael O'Donnell . A programming language theorem which is independent of Peano arithmetic.
Negation can be exponentially powerful.
Joseph Ja'Ja' . On the complexity of bilinear forms with commutativity. Andrew Chi-Chih Yao . The pebbling problem is complete in polynomial space. Completeness classes in algebra.