https://hal.inria.fr/inria-00456011Williams, RyanRyanWilliamsIBM Almaden Research Center [San Jose] - IBMAlternation-Trading Proofs, Linear Programming, and Lower BoundsHAL CCSD2010time-space tradeoffslower boundsalternationlinear programming[INFO.INFO-CC] Computer Science [cs]/Computational Complexity [cs.CC][INFO.INFO-AI] Computer Science [cs]/Artificial Intelligence [cs.AI]Loria, PublicationsJean-Yves Marion and Thomas Schwentick2010-02-11 15:25:392010-02-11 17:25:372010-02-11 17:25:37enConference papersapplication/pdf1A 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, Mod6-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 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.