Hard QBFs for Merge Resolution

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Beyersdorff, Olaf, Blinkhorn, Joshua, Mahajan, Meena, Peitl, Tomáš, Sood, Gaurav
Format: Preprint
Published: 2020
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913497403621376
author Beyersdorff, Olaf
Blinkhorn, Joshua
Mahajan, Meena
Peitl, Tomáš
Sood, Gaurav
author_facet Beyersdorff, Olaf
Blinkhorn, Joshua
Mahajan, Meena
Peitl, Tomáš
Sood, Gaurav
contents We prove the first genuine QBF proof size lower bounds for the proof system Merge Resolution (MRes [Olaf Beyersdorff et al., 2020]), a refutational proof system for prenex quantified Boolean formulas (QBF) with a CNF matrix. Unlike most QBF resolution systems in the literature, proofs in MRes consist of resolution steps together with information on countermodels, which are syntactically stored in the proofs as merge maps. As demonstrated in [Olaf Beyersdorff et al., 2020], this makes MRes quite powerful: it has strategy extraction by design and allows short proofs for formulas which are hard for classical QBF resolution systems. Here we show the first genuine QBF exponential lower bounds for MRes, thereby uncovering limitations of MRes. Technically, the results are either transferred from bounds from circuit complexity (for restricted versions of MRes) or directly obtained by combinatorial arguments (for full MRes). Our results imply that the MRes approach is largely orthogonal to other QBF resolution models such as the QCDCL resolution systems QRes and QURes and the expansion systems $\forall$Exp+Res and IR.
format Preprint
id arxiv_https___arxiv_org_abs_2012_06779
institution arXiv
publishDate 2020
record_format arxiv
spellingShingle Hard QBFs for Merge Resolution
Beyersdorff, Olaf
Blinkhorn, Joshua
Mahajan, Meena
Peitl, Tomáš
Sood, Gaurav
Computational Complexity
Logic in Computer Science
03F20
We prove the first genuine QBF proof size lower bounds for the proof system Merge Resolution (MRes [Olaf Beyersdorff et al., 2020]), a refutational proof system for prenex quantified Boolean formulas (QBF) with a CNF matrix. Unlike most QBF resolution systems in the literature, proofs in MRes consist of resolution steps together with information on countermodels, which are syntactically stored in the proofs as merge maps. As demonstrated in [Olaf Beyersdorff et al., 2020], this makes MRes quite powerful: it has strategy extraction by design and allows short proofs for formulas which are hard for classical QBF resolution systems. Here we show the first genuine QBF exponential lower bounds for MRes, thereby uncovering limitations of MRes. Technically, the results are either transferred from bounds from circuit complexity (for restricted versions of MRes) or directly obtained by combinatorial arguments (for full MRes). Our results imply that the MRes approach is largely orthogonal to other QBF resolution models such as the QCDCL resolution systems QRes and QURes and the expansion systems $\forall$Exp+Res and IR.
title Hard QBFs for Merge Resolution
topic Computational Complexity
Logic in Computer Science
03F20
url https://arxiv.org/abs/2012.06779