Skip to content

feat: add generalized topological Poincaré in dim ≥ 5 (Smale) eval problem#296

Open
kim-em wants to merge 1 commit into
mainfrom
eval/poincare-high-dim-topological
Open

feat: add generalized topological Poincaré in dim ≥ 5 (Smale) eval problem#296
kim-em wants to merge 1 commit into
mainfrom
eval/poincare-high-dim-topological

Conversation

@kim-em
Copy link
Copy Markdown
Collaborator

@kim-em kim-em commented May 23, 2026

This PR adds the generalized topological Poincaré conjecture in dimensions ≥ 5 as a new lean-eval challenge problem: for n ≥ 5, every Hausdorff n-manifold homotopy-equivalent to 𝕊ⁿ is homeomorphic to 𝕊ⁿ.

Specialization to n ≥ 5 of mathlib's generalized proof_wanted ContinuousMap.HomotopyEquiv.nonempty_homeomorph_sphere in Mathlib/Geometry/Manifold/PoincareConjecture.lean. Stephen Smale 1961 (Ann. of Math. 74), originally for smooth M via the h-cobordism theorem (Smale's main contribution); the topological version (no smoothness assumption) was completed by Newman in 1966 and Connell in 1967. Smale received the Fields Medal in 1966.

mathlib has homotopy equivalences (≃ₕ), homeomorphisms (≃ₜ), ChartedSpace, and the unit sphere as a topological space — but no h-cobordism theorem, no handle decompositions, and no Poincaré conjecture in any dimension.

Companion problems: #293 (3D topological, Perelman), #294 (3D smooth, Perelman), #295 (4D topological, Freedman).

🤖 Prepared with Claude Code

…le) eval problem

This PR adds Smale's generalized topological Poincaré conjecture in
dimensions n ≥ 5 as a new eval problem: every Hausdorff n-manifold
homotopy-equivalent to 𝕊ⁿ is homeomorphic to 𝕊ⁿ. Specialization to
n ≥ 5 of mathlib's generalized `proof_wanted`. Smale 1961 (Fields
Medal 1966) for smooth M via the h-cobordism theorem; topological
version completed by Newman 1966 and Connell 1967.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Labels

None yet

Projects

None yet

Development

Successfully merging this pull request may close these issues.

1 participant