Creative Commons Attribution 3.0 Unported license
The Minimum Circuit Size Problem (MCSP) and a related problem (MKTP) that deals with time-bounded Kolmogorov complexity are prominent candidates for NP-intermediate status. We show that, under very modest cryptographic assumptions (such as the existence of one-way functions), the problem of approximating the minimum circuit size (or time-bounded Kolmogorov complexity) within a factor of n^{1 - o(1)} is indeed NP-intermediate. To the best of our knowledge, these problems are the first natural NP-intermediate problems under the existence of an arbitrary one-way function.
We also prove that MKTP is hard for the complexity class DET under
non-uniform NC^0 reductions. This is surprising, since prior work on MCSP and MKTP had highlighted weaknesses of "local" reductions such as NC^0 reductions. We exploit this local reduction to obtain several new consequences:
* MKTP is not in AC^0[p].
* Circuit size lower bounds are equivalent to hardness of a relativized version MKTP^A of MKTP under a class of uniform AC^0 reductions, for a large class of sets A.
* Hardness of MCSP^A implies hardness of MKTP^A for a wide class of
sets A. This is the first result directly relating the complexity of
MCSP^A and MKTP^A, for any A.
@InProceedings{allender_et_al:LIPIcs.MFCS.2017.54,
author = {Allender, Eric and Hirahara, Shuichi},
title = {{New Insights on the (Non-)Hardness of Circuit Minimization and Related Problems}},
booktitle = {42nd International Symposium on Mathematical Foundations of Computer Science (MFCS 2017)},
pages = {54:1--54:14},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-046-0},
ISSN = {1868-8969},
year = {2017},
volume = {83},
editor = {Larsen, Kim G. and Bodlaender, Hans L. and Raskin, Jean-Francois},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.MFCS.2017.54},
URN = {urn:nbn:de:0030-drops-80636},
doi = {10.4230/LIPIcs.MFCS.2017.54},
annote = {Keywords: computational complexity, Kolmogorov complexity, circuit size}
}