English

Beyond Natural Proofs: Hardness Magnification and Locality

Computational Complexity 2019-11-20 v1 Discrete Mathematics Combinatorics

Abstract

Hardness magnification reduces major complexity separations (such as EXPNC1\mathsf{\mathsf{EXP}} \nsubseteq \mathsf{NC}^1) to proving lower bounds for some natural problem QQ against weak circuit models. Several recent works [OS18, MMW19, CT19, OPS19, CMMW19, Oli19, CJW19a] have established results of this form. In the most intriguing cases, the required lower bound is known for problems that appear to be significantly easier than QQ, while QQ itself is susceptible to lower bounds but these are not yet sufficient for magnification. In this work, we provide more examples of this phenomenon, and investigate the prospects of proving new lower bounds using this approach. In particular, we consider the following essential questions associated with the hardness magnification program: Does hardness magnification avoid the natural proofs barrier of Razborov and Rudich [RR97]? Can we adapt known lower bound techniques to establish the desired lower bound for QQ?

Keywords

Cite

@article{arxiv.1911.08297,
  title  = {Beyond Natural Proofs: Hardness Magnification and Locality},
  author = {Lijie Chen and Shuichi Hirahara and Igor C. Oliveira and Jan Pich and Ninad Rajgopal and Rahul Santhanam},
  journal= {arXiv preprint arXiv:1911.08297},
  year   = {2019}
}