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WikipediaGeneral topology

The Bing-Borsuk Conjecture

The Bing-Borsuk Conjecture: every nn-dimensional homogeneous absolute neighborhood retract is a topological nn-manifold. A topological space XX is an nn-dimensional manifold when T2Space X ∧ Nonempty (ChartedSpace (Fin n → ℝ) X). The hypothesis `[Metr...

Mathematical statement

The Bing-Borsuk Conjecture: every nn-dimensional homogeneous absolute neighborhood retract is a topological nn-manifold. A topological space XX is an nn-dimensional manifold when T2Space X ∧ Nonempty (ChartedSpace (Fin n → ℝ) X). The hypothesis [MetrizableSpace X] implies T2Space X so this does not appear in the conclusion.

Statement source: Wikipedia statement material

Statement terms: CC-BY-SA-4.0

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Statement artifacts, not proofs

These records expose exact Lean propositions and statement-only wrappers. Defining a proposition does not supply a proof of it. A placeholder-bearing target also contains no proof. Elaboration checks syntax and types; it does not certify that a formalization perfectly captures every nuance of the informal problem.

Pinned Lean formulation 1

bing_borsuk_conjecture

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem bing_borsuk_conjecture :  n : ,  (X : Type) [TopologicalSpace X] [MetrizableSpace X] [HomogeneousSpace X] [IsAbsoluteNeighborhoodRetract X],    HasLebesgueCoveringDimensionEq X n  Nonempty (ChartedSpace (Fin n  ) X) := by  sorry
Statement source
Formal Conjectures
Lean version
v4.27.0
Placeholder
Present; no proof artifact
Source evidence
Pinned source index
Fidelity review
Community formulation

References