Alternation-Trading Proofs, Linear Programming, and Lower Bounds

Author Ryan Williams

Thumbnail PDF


  • Filesize: 314 kB
  • 12 pages

Document Identifiers

Author Details

Ryan Williams

Cite AsGet BibTex

Ryan Williams. Alternation-Trading Proofs, Linear Programming, and Lower Bounds. In 27th International Symposium on Theoretical Aspects of Computer Science. Leibniz International Proceedings in Informatics (LIPIcs), Volume 5, pp. 669-680, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2010)


A fertile area of recent research has demonstrated concrete polynomial time lower bounds for solving natural hard problems on restricted computational models. Among these problems are Satisfiability, Vertex Cover, Hamilton Path, $\text{MOD}_6\text{-SAT}$, Majority-of-Majority-SAT, and Tautologies, to name a few. The proofs of these lower bounds follow a certain proof-by-contradiction strategy that we call {\em alternation-trading}. An important open problem is to determine how powerful such proofs can possibly be. We propose a methodology for studying these proofs that makes them amenable to both formal analysis and automated theorem proving. We prove that the search for better lower bounds can often be turned into a problem of solving a large series of linear programming instances. Implementing a small-scale theorem prover based on this result, we extract new human-readable time lower bounds for several problems. This framework can also be used to prove concrete limitations on the current techniques.
  • Time-space tradeoffs
  • lower bounds
  • alternation
  • linear programming


  • Access Statistics
  • Total Accesses (updated on a weekly basis)
    PDF Downloads