On the time and tape complexity of languages I

Abstract

We investigate the following: (1) the relationship between the classes of languages accepted by deterministic and nondeterministic polynomial time bounded Turing machines; (2) the time and tape complexity of many predicates on the regular sets; (3) the relationship between the classes of languages accepted by deterministic or nondeterministic polynomial time bounded Turing machines and the class of languages accepted by polynomial tape bounded Turing machines; and (4) the complexity of many predicates about stack automata. We find several problems with nonpolynomial lower complexity bounds.