Random-Access Stored-Program Machines, an Approach to Programming Languages
Journal of the ACM (JACM)
A Machine-Independent Theory of the Complexity of Recursive Functions
Journal of the ACM (JACM)
Some Results on Tape-Bounded Turing Machines
Journal of the ACM (JACM)
An Overview of the Theory of Computational Complexity
Journal of the ACM (JACM)
Formal languages and their relation to automata
Formal languages and their relation to automata
Hierarchies of memory limited computations
FOCS '65 Proceedings of the 6th Annual Symposium on Switching Circuit Theory and Logical Design (SWCT 1965)
Time bounded random access machines
Journal of Computer and System Sciences
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For various settings and various dynamic criteria for gauging optimality of programs,there does not exist a master program (optimizer) such that if P is any program which computes a partial function pocessing an optimal program, then , operating on the program P as input, halts eventually and outputs an optimal program P for computing that partial function. Optimality can be gauged by a criterion suggested by a variant of M. Blum's compression theorem for an arbitrary complexity measure, by optimality except for a linear factor for amount of memory used by a Turing machine, or by optimality within @e on a RASP. Thus, our techniques are compatible with techniques for producing optimal programs which are as diverse as upward diagonalization, downward diagonalization, and the size arguments of Hartmanis. Our nonexistence results continue to hold even if we only ask that an optimizer behave properly when the input program P satisfies certain convergence properties (e.g., when P computes a total function) and possesses an equivalent optimal program which is neither too hard nor too easy to compute.