Conjectura
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Facts about Keller maps

isKellerMap_iff_det_eq_Ctheorem

The unit-determinant hypothesis really is "non-zero constant determinant" over a field. A sanity theorem: it pins the formalization to the literature's statement.

theorem isKellerMap_iff_det_eq_C {k σ : Type} [Field k] [Fintype σ] [DecidableEq σ]
    (F : RegularFunction k σ σ) :
    IsKellerMap F ↔ (∃ c : k, c ≠ 0 ∧ F.Jacobian.det = MvPolynomial.C c) := by
  simp [IsKellerMap, MvPolynomial.isUnit_iff_eq_C_of_isReduced, isUnit_iff_ne_zero]

isKellerMap_idtheorem

Non-vacuity: the hypothesis is satisfiable, so the conjecture is not quantifying over an empty class.

theorem isKellerMap_id {k σ : Type} [CommRing k] [Fintype σ] [DecidableEq σ] :
    IsKellerMap (RegularFunction.id k σ) := by
  suffices (RegularFunction.id k σ).Jacobian = 1 by simp [IsKellerMap, this]
  ext i j
  simp [RegularFunction.Jacobian, RegularFunction.id, Matrix.one_eq_pi_single]

Builds on

import Conjectura.Theorems.Mathematics.AlgebraicGeometry.KellerMap · maintainer — open · raw source

Adapted for Conjectura from formal-conjectures (Google DeepMind), `FormalConjectures/Wikipedia/JacobianConjecture.lean`. Split into one concept per module; no mathematical content changed.

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Released under Apache 2.0 license as described in the file LICENSE.
Authors: The Formal Conjectures Authors

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