Parallel computable higher type functionals - Foundations of Computer Science, 1993. Proceedings., 34th Annual Symposium on
نویسنده
چکیده
The primary aim of this paper is to introduce higher type analogues of some familiar parallel complexity classes, and to show that these higher type classes can be characterized in significantly different ways. Recursion-theoretic, proof-theoretic and machine-theoretic characterizations are given for various classes, providing evidence of their naturalness. In this section, we motivate the approach of our work. In proof theory, primitive recursive functionals of higher type were introduced in Godel’s Dialect i c ~ [13] paper, where they were used to “witness” the truth of arithmetic formulas. For instance, a function f witnesses the formula Vx3y0(z1 y), where 0 is quantifier-free, provided that
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