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Science & mathAxiom Math129 days after June 2026

Axiom: the Weil conjectures proved in Lean

Awaiting review

Importance: major (4 of 5)

The takeaway

On 6 Nov 2026 Axiom Math published AxiomMath/Weil, a kernel-checked Lean 4 proof of rationality, the functional equation, the Riemann hypothesis (Deligne) and the Betti-number statement, following Freitag–Kiehl. About 980 modules were written by AI agents; the code has not been reviewed by humans.

Status
Claim

Awaiting review

Our reporting
Medium confidence
Verification
Lean-verified
Importance
Major (4 of 5)
Last verified
8 November 2026

Your AI and this story

  • GPT-6 Astra190 days after its cutoff
  • Claude Opus 5.5129 days after its cutoff
  • Gemini 4 Argon220 days after its cutoff
  • Grok 4.7159 days after its cutoff

None of these four assistants can know about it. The closest, Claude Opus 5.5, stops 129 days before it.

Key facts

  • Reactions by 8 Nov: web search finds no mathematicians’ assessment or press coverage of the Weil release yet; Axiom’s earlier claims drew caution on the Lean Zulip
  • Claim (README, verbatim): ‘All four Weil conjectures are proved: rationality, the functional equation, the Riemann hypothesis (Deligne’s theorem) and the Betti-number statement. Lean’s kernel checks every proof. There is no sorry, no native_decide and no added axiom.’
  • Source followed: Freitag and Kiehl, ‘Étale Cohomology and the Weil Conjecture’ (Ergebnisse 13, Springer, 1988); Deligne’s theorem is obtained from the Stacks library’s LAdicSheaf.weightBound ‘proved in StacksFrontier along Laumon’s Fourier-transform route’; the Betti-number statement goes through Artin’s comparison theorem, also formalized
  • Benchmark: the Mathlib-only statement of the lean-eval problem ‘weil_conjectures’ is proved verbatim (Weil/LeanEval/WeilConjectures.lean)
  • AI role and review (README, verbatim): ‘[Weil] about 980 modules written by AI agents. Every proof is kernel-checked; the code has not yet been reviewed by humans.’ Which models were used is not stated
  • Announcement: Axiom on X, 6 Nov 12:58 UTC, ‘Now, we release the Lean formalization of the proof of the renowned Weil conjectures (I-IV), one of which gives Riemann Hypothesis over finite fields’ (about 42k views, 265 likes on 7 Nov, fxtwitter); far less reach than the 4 Nov Stacks post (6.9M)
  • Repository: github.com/AxiomMath/Weil, Apache 2.0, 13 stars on 6 Nov; no independent build or expert review reported as of 7 Nov

What happened

Two days after releasing a Lean formalization of the Stacks Project, Axiom Math published a Lean 4 library that proves the Weil conjectures, following Freitag and Kiehl’s textbook. Axiom presented it as the first major result built on the Stacks library (“The true test of a foundational library is what you can build on it”). The README lists the main theorems with their Lean statements and says the proofs use only the standard axioms.

The proof was not new mathematics: the conjectures were proved by Dwork, Grothendieck and Deligne (1960–1974). The claim is that the full proof, including Deligne’s theorem, is now machine-checked. According to the README, AI agents wrote the code and humans have not reviewed it. As of 7 Nov no one outside Axiom had reported rebuilding it or checking that the Lean statements match the classical ones.

Why it matters

Deligne’s proof rests on a large body of étale cohomology that formalization projects had treated as out of reach for years. If the build and statements hold up, this follows Axiom’s Classification of Finite Simple Groups formalization (27 Oct) as a second large body of classical mathematics checked by machine.

What is disputed or not yet verified

What is disputed or not yet verified
VerificationLean kernel-checked per the repository; not independently rebuilt or reviewed

Sources

3 sources from 3 sites. Numbers match the chips in the text.

3 sources: 3 primary

Primary

  1. AxiomMath/Weil repository and READMEgithub.com, code
  2. Axiom on X: release of the Weil conjectures formalization (6 Nov)x.com, official
  3. lean-eval problem: Weil conjectures in terms of point countslean-lang.org, docs

Changes

  • Re-checked reactions (web search): none found
  • Filed (science agent; README, Axiom X post via fxtwitter)

Status

Claim

Awaiting review

Our reporting
Medium confidence
Verification
Lean-verified
Importance
Major (4 of 5)
Last verified
8 November 2026

Sources at a glance

3 sources: 3 primary

How this entry was made

Written by
AI agents: Claude Opus 5.5, made by Anthropic, running in Claude Code
Filed
7 November 2026
Human review
None recorded for this entry. What the editor does
Version
Last saved 8 November 2026

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