,
Dana Moshkovitz
Creative Commons Attribution 4.0 International license
We prove that for some constant a > 1, for all k ≤ a, MATIME[n^{k+o(1)}]/1 ⊄ SIZE[O(n^k)], for some specific o(1) function. This is a super linear polynomial circuit lower bound.
Previously, Santhanam [Santhanam, 2007] showed that there exists a constant c > 1 such that for all k > 1: MATIME[n^{ck}]/1 ⊄ SIZE[O(n^k)]. Inherently to Santhanam’s proof, c is a large constant and there is no upper bound on c. Using ideas from Murray and Williams [Murray and Williams, 2018], one can show for all k > 1: MATIME [n^{10 k²}]/1 ⊄ SIZE[O(n^k)].
To prove this result, we construct the first PCP for SPACE[n] with quasi-linear verifier time: our PCP has a Õ(n) time verifier, Õ(n) space prover, O(log(n)) queries, and polynomial alphabet size. Prior to this work, PCPs for SPACE[O(n)] had verifiers that run in Ω(n²) time. This PCP also proves that NE has MIP verifiers which run in time Õ(n).
@InProceedings{cook_et_al:LIPIcs.APPROX/RANDOM.2023.55,
author = {Cook, Joshua and Moshkovitz, Dana},
title = {{Tighter MA/1 Circuit Lower Bounds from Verifier Efficient PCPs for PSPACE}},
booktitle = {Approximation, Randomization, and Combinatorial Optimization. Algorithms and Techniques (APPROX/RANDOM 2023)},
pages = {55:1--55:22},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-296-9},
ISSN = {1868-8969},
year = {2023},
volume = {275},
editor = {Megow, Nicole and Smith, Adam},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.APPROX/RANDOM.2023.55},
URN = {urn:nbn:de:0030-drops-188805},
doi = {10.4230/LIPIcs.APPROX/RANDOM.2023.55},
annote = {Keywords: MA, PCP, Circuit Complexity}
}