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Alternation-Trading Proofs, Linear Programming, and Lower Bounds Williams, Ryan Time-space tradeoffs lower bounds alternation linear programming 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. Schloss Dagstuhl – Leibniz-Zentrum für Informatik Ryan Williams 2010 Is Part Of LIPIcs, Volume 5, 27th International Symposium on Theoretical Aspects of Computer Science (2010) InProceedings Text doc-type:ResearchArticle publishedVersion application/pdf doi:10.4230/LIPIcs.STACS.2010.2494 urn:nbn:de:0030-drops-24940 https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.STACS.2010.2494 eng https://creativecommons.org/licenses/by-nd/3.0/legalcode