OAI/RingTheory/DirectFiniteness/SlabPartition.lean
9 declarations, 0 contain sorry, 0 declared as axioms
- def
OAI.KaplanskyCounterexample.FiniteGeometry.NoEigenvectorline 14 - lemma
OAI.KaplanskyCounterexample.FiniteGeometry.independent_pair_of_noEigenvectorline 17 - theorem
OAI.KaplanskyCounterexample.FiniteGeometry.existsUnique_slab_functionalline 22 - def
OAI.KaplanskyCounterexample.FiniteGeometry.slabLineline 40 - lemma
OAI.KaplanskyCounterexample.FiniteGeometry.slabLine_off_axisline 43 - lemma
OAI.KaplanskyCounterexample.FiniteGeometry.slabLine_functional_ne_zeroline 50 - theorem
OAI.KaplanskyCounterexample.FiniteGeometry.slab_partitionline 58Source documentation
The axis and the displayed lifted lines partition the slab.
theorem slab_partition [FiniteDimensional Q P] (hd : finrank Q P = 2) (J : P →ₗ[Q] P) (hJ : NoEigenvector J) (p : P × Q) : p.1 = 0 ∨ ∃! γ : {γ : P →ₗ[Q] Q // γ ≠ 0}, p ∈ slabLine J γ.val := by …Mentions: OAI.KaplanskyCounterexample.FiniteGeometry.NoEigenvector, OAI.KaplanskyCounterexample.FiniteGeometry.slabLine
- theorem
OAI.KaplanskyCounterexample.FiniteGeometry.slabLine_is_lineline 73Source documentation
The displayed set is a full affine line, not merely an arbitrary part of the partition; its direction has nonzero projection to the plane.
theorem slabLine_is_line [FiniteDimensional Q P] (hd : finrank Q P = 2) (J : P →ₗ[Q] P) (γ : P →ₗ[Q] Q) (hγ : γ ≠ 0) : ∃ u v : P × Q, v.1 ≠ 0 ∧ slabLine J γ = Set.range (fun t : Q => u + t • v) := by …Mentions: OAI.KaplanskyCounterexample.FiniteGeometry.slabLine
- theorem
OAI.KaplanskyCounterexample.FiniteGeometry.exists_noEigenvector_of_quadraticline 129Source documentation
A quadratic extension supplies the operator without eigenvectors.
theorem exists_noEigenvector_of_quadratic (hd : finrank Q F = 2) : ∃ J : F →ₗ[Q] F, NoEigenvector J := by …Mentions: OAI.KaplanskyCounterexample.FiniteGeometry.NoEigenvector