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Anthropic published its own refutation of the Exponential Time Hypothesis, with a Lean 4 proof alongside it

AspireAI community · Anthropic (GitHub)
*Anthropic put its own refutation of the Exponential Time Hypothesis in public, with a Lean 4 proof alongside it.* The paper, "A 2^o(n) Time Algorithm for 3-SAT," is credited to Claude and gives a deterministic sub-exponential algorithm for 3-SAT, refuting a 1999 conjecture used across hundreds of papers. *The provenance line is the story.* The paper says the core algorithm was found on October 16 by an internal Claude research model with 14 million output tokens and no human input. Anthropic researchers then worked with Claude on the write-up. It also records a concurrent claim from an OpenAI model. The Lean formalization was itself written by AI models. The honest limit: the result is purely asymptotic and says nothing about solving formulas in practice. https://github.com/anthropics/formal-math/tree/main/eth
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