feat: add Jordan curve theorem eval problem#305
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§48 of Knill's "Some Fundamental Theorems in Mathematics" (Camille Jordan, 1887). Every continuous injection r : S¹ → ℝ² has a complement with exactly two connected components. Mathlib has Metric.sphere, EuclideanSpace, ConnectedComponents, and Nat.card, but no Jordan curve theorem, no winding numbers / invariance of domain in a form that would discharge it. Stateable with zero new definitions. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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This PR adds an eval problem for the Jordan curve theorem (Camille
Jordan, 1887): every continuous injection
r : S¹ → ℝ²has acomplement with exactly two connected components. §48 of Knill's
Some Fundamental Theorems in Mathematics.
Mathlib has
Metric.sphere,EuclideanSpace,ConnectedComponents,and
Nat.card, but no Jordan curve theorem (grep -ri 'jordan curve' Mathlib/: no hits), no winding numbers / invariance of domain in aform that would discharge it. Stateable with zero new definitions.
Formalized in Mizar (Korniłowicz et al., 2005) and HOL Light
(Hales, 2007); item #14 on Freek Wiedijk's 100-theorems list (not yet
in Lean).
🤖 Prepared with Claude Code