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A second step towards complexity-theoretic analogs of Rice's Theorem

✍ Scribed by Lane A. Hemaspaandra; Jörg Rothe


Publisher
Elsevier Science
Year
2000
Tongue
English
Weight
122 KB
Volume
244
Category
Article
ISSN
0304-3975

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✦ Synopsis


Rice's Theorem states that every nontrivial language property of the recursively enumerable sets is undecidable. Borchert and Stephan (1997) initiated the search for complexity-theoretic analogs of Rice's Theorem. In particular, they proved that every nontrivial counting property of circuits is UP-hard, and that a number of closely related problems are SPP-hard.

The present paper studies whether their UP-hardness result itself can be improved to SPPhardness. We show that their UP-hardness result cannot be strengthened to SPP-hardness unless unlikely complexity class containments hold. Nonetheless, we prove that every P-constructibly bi-inÿnite counting property of circuits is SPP-hard. We also raise their general lower bound from unambiguous nondeterminism to constant-ambiguity nondeterminism.