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TopicsAlpöge's ℂ³ map Algebraic geometry Jacobian conjecture

The Alpöge–Fable map F:ℂ³→ℂ³ has Jacobian determinant identically equal to −2.

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2 sources · no origin · 2 untraced

2 Untraced

An Independent Lean 4 Verification of the Alpöge–Fable Counterexample Untraced · nothing upstream recorded

Formal Verification of an Explicit Counterexample to the Jacobian Conjecture Untraced · nothing upstream recorded

originuntraced

Isabelle proves that the formal Jacobian entries are the corresponding complex analytic partial derivatives and that the determinant is identically \(-2\).

Formal Verification of an Explicit Counterexample to the Jacobian Conjectureextraction 0.75

Describing the specific verified property of the map's Jacobian.

The claim, due to Alpöge and Fable: det Jac F ≡ −2 identically

An Independent Lean 4 Verification of the Alpöge–Fable Counterexampleextraction 0.90

Property of the specific polynomial map F = (P,Q,R).

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Created by extractor · Sep 16, 2026. Every judgment on this page is accompanied by a reasoning trace.