Paper Info
Title
Nearly-Exponential Size Lower Bounds for Symbolic Quantifier Elimination Algorithms and OBDD-Based Proofs of Unsatisfiability
Abstract
We demonstrate a family of propositional formulas in conjunctive normal form so that a formula of size $N$ requires size $2^{\Omega(\sqrt[7]{N/logN})}$ to refute using the tree-like OBDD refutation system of Atserias, Kolaitis and Vardi with respect to all variable orderings. All known symbolic quantifier elimination algorithms for satisfiability generate tree-like proofs when run on unsatisfiable CNFs, so this lower bound applies to the run-times of these algorithms. Furthermore, the lower bound generalizes earlier results on OBDD-based proofs of unsatisfiability in that it applies for all variable orderings, it applies when the clauses are processed according to an arbitrary schedule, and it applies when variables are eliminated via quantification.
Year
Venue
Keywords
2007
Electronic Colloquium on Computational Complexity
lower bound,conjunctive normal form,quantifier elimination,computational complexity,satisfiability
DocType
Volume
Citations 
Journal
abs/cs/0701054
4
PageRank 
References 
Authors
0.40
27
1
Name
Order
Citations
PageRank
Nathan Segerlind122311.22