On the structure of linear-time reducibility

Philippe Chapdelaine

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On the structure of linear-time reducibility

Philippe Chapdelaine

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Abstract

In 1975, Ladner showed that under the hypothesis that P is not equal to NP, there exists a language which is neither in P, nor NP-complete. This result was latter generalized by Schoning and several authors to various polynomial-time complexity classes. We show here that such results also apply to linear-time reductions on RAMs (resp. Turing machines), and hence allow for separation results in linear-time classes similar to Ladner's ones for polynomial time.

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Philippe Chapdelaine. 2006-06-19. On the structure of linear-time reducibility. https://arxiv.org/abs/cs/0606080

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