feat(FLP): prove that asynchronous distributed consensus tolerating any non-zero number of faults is impossible - #765
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…ny non-zero number of faults is impossible
fmontesi
approved these changes
Aug 3, 2026
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This PR completes the proof that asynchronous distributed consensus tolerating any non-zero number of faults is impossible. The main theorem
OnePseudoConsensus.not_terminatingshows that every 1-tolerant pseudo-consensus algorithm has a fair execution which doesn't contain any fault but never reaches a consensus, which then implies that there cannot be a consensus algorithm that can tolerate even a single fault. This fair execution is constructed using the results obtained inFLP/OnePseudoConsensus.leanand the technical machinery developed inFLP/FairScheduler.lean.