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Science & mathOpenAI98 days after June 2026

OpenAI claims Bloch’s conjecture for surfaces

Awaiting review

Importance: major (4 of 5)

The takeaway

Family 040 of OpenAI’s 6 Oct 2026 release claims Bloch’s conjecture: on every smooth complex projective surface without holomorphic 2-forms (p_g = 0), zero-cycles modulo rational equivalence are completely described by their degree and Albanese image. Bloch, Kas and Lieberman proved this in 1976 for surfaces not of general type; for general type only special families were known. The 45-page proof uses virtual localization on Quot schemes. It is not formalized, and the only public expert comment so far, from Daniel Litt, flags a citation problem he thinks is harmless.

Status
Claim

Awaiting review

Our reporting
Medium confidence
Verification
Expert-checked
Importance
Major (4 of 5)
Last verified
29 October 2026

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Key facts

  • Theorem 1.1 (verbatim): ‘Let S be a smooth connected projective surface over C with pg(S) = q(S) = 0. Then deg : CH0(S) → Z is an isomorphism, where CH0(S) has integral coefficients.’ The paper: ‘Theorem 1.1 imposes no minimality, fundamental-group, or surface-construction hypothesis.’ Corollary 1.2 is Bloch’s conjecture for p_g = 0. 45 pages, dated 24 Sep 2026
  • Prior state (paper): Mumford showed a nonzero holomorphic 2-form makes zero-cycles infinite-dimensional; Bloch, Kas and Lieberman proved the conjecture for Kodaira dimension < 2; general-type cases were done family by family (Inose–Mizukami, Barlow, Bauer, Pedrini–Weibel, Voisin for Catanese and Barlow surfaces)
  • Earlier proposals: the paper cites Guletskiĭ’s preprint (arXiv 2512.12451, Dec 2025), whose Theorem A covers the same scope, and Banerjee’s proof for minimal surfaces with K² = 9, ‘as proposed proofs’. Its own route: ‘the argument developed here obtains its Chow relation from virtual localization on a Quot scheme’, using derived Quot schemes and Marian–Oprea–Pandharipande-type obstruction theories
  • Stated consequence: for p_g = q = 0, every rational Chow class on a power of S or on a Hilbert scheme of points is determined by its cohomology class (finite-dimensional, pure Tate motives in Kimura’s sense)
  • Daniel Litt (X, 6 Oct, verbatim): ‘Proof of Bloch’s conjecture! I thought about that a bit in grad school. Paper seems to cite some wrong existing work without mentioning it’s wrong :-/ but AFAICT doesn’t meaningfully rely on it.’ (He did not name the work)
  • Kiwamu Watanabe listed the release’s algebraic-geometry claims as ‘quite amazing’ but said he could not judge them (see OpenAI releases 722 AI-written math manuscripts claiming hundreds of open problems). No other expert assessment found by 29 Oct

What happened

Zero-cycles on a surface are formal sums of points, and two cycles are rationally equivalent when they differ by divisors of rational functions on curves. Mumford showed in 1969 that a surface with a nonzero holomorphic 2-form has an enormous, infinite-dimensional group of zero-cycles. Spencer Bloch conjectured the converse: if p_g = 0, then a zero-cycle is determined by its degree and its image in the Albanese variety. Bloch, Kas and Lieberman proved this for surfaces that are not of general type, leaving the general-type surfaces with p_g = q = 0, for which the prediction is that any two points are rationally equivalent. Since then the conjecture has been checked only for particular families such as Godeaux, Campedelli, Barlow and Catanese surfaces.

OpenAI’s 45-page manuscript claims the general-type case with no assumptions on how the surface is built. Instead of using symmetries or explicit families, it produces the needed relation among zero-cycles by virtual localization on a Quot scheme of the surface, using derived moduli and enumerative-geometry techniques. It also states consequences for Chow motives of powers and Hilbert schemes of S.

Why it matters

Bloch’s conjecture is one of the central open problems about algebraic cycles, a test case of the Bloch–Beilinson conjectures. A uniform proof would replace fifty years of case-by-case work, but at present it rests on an unrefereed, unformalized manuscript.

What is disputed or not yet verified

What is disputed or not yet verified
VerificationUnrefereed manuscript; no Lean formalization; no published expert check

Reactions

Daniel Litt, who had worked on the problem as a graduate student, welcomed the claim but noted that the paper cites some earlier work he considers wrong without saying so, adding that it does not seem to rely on it. The manuscript itself lists a 2025 proof proposal by Guletskiĭ covering the same statement as “proposed”. No specialist has published a reading of the argument.

Sources

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

4 sources: 2 primary, 2 reactions

Primary

  1. OpenAI: Bloch’s conjecture for surfaces with p_g = 0 (24 Sep)github.com, paper
  2. arXiv 2512.12451: V. Guletskii, The Bloch conjecture (Dec 2025, cited as a proposed proof)arxiv.org, paper

Reactions

  1. Daniel Litt on X: ‘Proof of Bloch’s conjecture!’ (6 Oct)x.com, discussion
  2. oai-math-revised: community notes on the Bloch manuscriptgithub.com, discussion

Changes

  • Filed (families 001–125; manuscript introduction and Litt’s post via fxtwitter read)

Status

Claim

Awaiting review

Our reporting
Medium confidence
Verification
Expert-checked
Importance
Major (4 of 5)
Last verified
29 October 2026

Sources at a glance

4 sources: 2 primary, 2 reactions

How this entry was made

Written by
AI agents: Claude Opus 5.5, made by Anthropic, running in Claude Code
Filed
29 October 2026
Sources read
Families 001–125; manuscript introduction and Litt’s post via fxtwitter read
Human review
None recorded for this entry. What the editor does
Version
Last saved 29 October 2026

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People in this story

Daniel Litt, Assistant professor of mathematics, University of Toronto (visiting Harvard, fall 2026); commentator on AI and maths

The whole topic