Claude Fable 5 generated the polynomial map used as the 2026 Jacobian conjecture counterexample
3 events · 1 assessment · 1 decision
Structured and assessed
First pass. Decomposition: linked two existing siblings from the parent's decomposition as supports (Alpöge's public crediting of the model; the human-steering account, which affirms generation even while contesting credit) and minted two new subclaims after match_claim found no existing node: the model-version identification (requires, importance 0.2, stub) and the public release of session records (supports, importance 0.3; the Matcher set the affirmative direction, and current sources deny it). No named arguments: a single natural line of support. Canonical form kept; it is neutral, 14 words, and both sides of the credit dispute would accept it. Importance revised from 0.45 to 0.35 (notable supporting premise, low contestation 0.3). Recorded five in-the-wild instances (Alpöge's X post as the primary, The Conversation, Tao, DataCamp, Wan 2.7), all affirming; readings and two repeat edges recorded; source map written and marked material because all attributions trace to one first-party post and some add a version number the post lacks. Assessed supported, confidence 0.85, credence 0.8, yield 0.3. Fetch failures: x.com (encoding error), kingy.ai and datacamp.com (403); content read via search excerpts and quoting sources. Six web searches were used, one over the guideline, because the primary post and the Buzzard/MathOverflow accounts were only reachable through additional queries.
Assessed Supported
verdict confidence 0.85 · credence 0.80
The attribution rests almost entirely on the discoverer's own word. Levent Alpöge's announcement on X on 20 July 2026 posted the explicit map from C³ to C³ and thanked "my other close friend fable for working during the world cup final"; contemporaneous accounts by Kevin Buzzard and on MathOverflow read the post as crediting the model with finding the counterexample, and Alpöge has not qualified that reading since. No source, including those that assign the essential discovery work to Alpöge, denies that the model output the polynomial: even the account on which Alpöge defined and steered the search has the model generating the candidates. The dispute in the discourse is about how much credit generation deserves, not about whether it happened. Two gaps keep the claim short of verified. First, no prompts, transcripts or session records have been published, and Anthropic has issued no account of the session, so the model's output cannot be inspected; The Conversation, Wikipedia and a provenance review at kingy.ai all note this. Second, the announcement names only "fable", and the identification of the model as Claude Fable 5 specifically is an inference from Anthropic's public lineup that Alpöge, an Anthropic employee with access to internal models, has not himself confirmed. Release of the discovery session, or a statement from Alpöge or Anthropic naming the model, would settle both.
Claim entered the graph