Rational Ellipticity, Entropy, Euler Characteristic, and Formality
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Definitions and mathematical statement
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Are almost nonnegatively curved manifolds rationally elliptic; do they admit Riemannian metrics with vanishing topological entropy; do nonnegatively curved manifolds have nonnegative Euler characteristic; and are positively curved manifolds formal?Formulation references: [S1], [S2].
Short English statement
Are almost nonnegatively curved manifolds rationally elliptic; do they admit Riemannian metrics with vanishing topological entropy; do nonnegatively curved manifolds have nonnegative Euler characteristic; and are positively curved manifolds formal?Sources
- S1 ULAM.AI and the UnsolvedMath Contributors, UnsolvedMath: A Curated Collection of Open Mathematics Problems, record 30001754 (OWR-5146-002). Catalogue attribution under CC BY 4.0. https://huggingface.co/datasets/ulamai/UnsolvedMath.
- S2 Original problem formulation and mathematical context. https://doi.org/10.4171/owr/2011/18.
Statement licence: CC-BY-SA-4.0 · Source file
Contributions 1
OpenAI claim summary for Math-2364
A topological Einstein-energy gap: The L2 gap explicitly assumes the Einstein classification and requires sufficiently small traceless-Ricci energy.
This page records partial support. Complete resolution of the catalogue question is not established by this record.
Rational Ellipticity, Entropy, Euler Characteristic, and Formality
OpenAI's claim
A topological Einstein-energy gap: Assuming the manuscript's normalized classification of nonnegatively curved Einstein four-manifolds, a sufficiently small scale-invariant $L^2$ trace-free Ricci energy is claimed to force a simply connected closed nonnegatively curved four-manifold to be diffeomorphic to $S^4$, $\mathbb{CP}^2$ or $S^2\times S^2$. No additional geometric bounds are imposed.Mathematical statement of the claimed result
Mathematical claim 1.
Assume the companion classification: every closed connected smooth four-manifold with $\operatorname{Ric}=3g$ and sectional curvature $\ge0$ has universal cover isometric to round $S^4$, Fubini--Study $\mathbb{CP}^2$ normalized by $\operatorname{Ric}=3g$, or $S^2(1/\sqrt3)\times S^2(1/\sqrt3)$. Under that explicit premise, the claim gives an absolute $\epsilon_0>0$ such that any closed connected simply connected smooth four-manifold with $\sec_g\ge0$ and \[\int_M\left|\operatorname{Ric}_g-\tfrac14\operatorname{Scal}_g g\right|^2\,dV_g<\epsilon_0\] is diffeomorphic, without specified orientation, to $S^4$, $\mathbb{CP}^2$ or $S^2\times S^2$. The conclusion is topological rather than isometric, and the theorem is expressly conditional on the classification premise.Outline of the argument
A topological Einstein-energy gap: A hypothetical countersequence is normalized and shown to satisfy initial geometry and Sobolev bounds. A uniform smoothing interval controls its high-curvature region and propagates the Einstein defect and negative-sectional-curvature error. The limit is a compact nonnegatively curved positive-Einstein space, whose companion classification identifies the topology and contradicts the sequence.Formal verification
Family 348 describes Lean coverage for the strict-positive-curvature Einstein classification; zero-plane rigidity and the small-energy gap are separate.A topological Einstein-energy gap: No manuscript-specific Comparator is listed in the pinned inventory.
The documented selection does not cover the entire manuscript assertion relevant here.
This site has not run the Lean development. These links describe OpenAI’s selected formal statements and should be read with their stated scope.
Status caveat
OpenAI reports that an internal model produced the manuscripts. Their arguments have not been independently verified as proofs by this site. Any portion outside the documented formal scope may contain mistakes, and the catalogue label reports the announced mathematical claim.Sources
- OpenAI, An L${}^{2}$ Einstein Gap for Nonnegatively Curved Four-Manifolds, 2026-10-05; citation key
OAI:An-L2-Einstein-Gap-for-Nonnegatively-Curved-Four-Manifolds-October-5-2026. PDF (GitHub); PDF (direct); Manuscript page and citation; Latest version; Statement source: thm:gap. - Family 348: Lean scope.
- OpenAI catalogue entry.