OAI/Topology/ArtinGroups/ParabolicIntersections/VisualFactorMalnormal.lean
5 declarations, 0 contain sorry, 0 declared as axioms
Weak malnormality for the vertex factors, and hence their parabolics.
- lemma
OAI.HarmonicArtin.ParabolicIntersections.trivial_pair_endpoint_typeline 15 - lemma
OAI.HarmonicArtin.ParabolicIntersections.visual_trivial_pair_distinct_typeline 41Source documentation
A nondegenerate segment with trivial stabilizer in either vertex orbit.
lemma visual_trivial_pair_distinct_type (hIrred : IsIrreducible M) (b : Bool) : ∃ u v : VisualVertex M Y Z, u≠v ∧ u.1=b ∧ v.1=b ∧ pairStabilizer (G := Artin M) u v=⊥ := by …Mentions: OAI.HarmonicArtin.ParabolicIntersections.IsIrreducible, OAI.HarmonicArtin.ParabolicIntersections.VisualVertex, OAI.HarmonicArtin.Artin
- lemma
OAI.HarmonicArtin.ParabolicIntersections.visual_trivial_pair_typeline 52Source documentation
Both endpoints may be taken in either vertex orbit.
lemma visual_trivial_pair_type (hIrred : IsIrreducible M) (b : Bool) : ∃ u v : VisualVertex M Y Z, u.1=b ∧ v.1=b ∧ pairStabilizer (G := Artin M) u v=⊥ := by …Mentions: OAI.HarmonicArtin.ParabolicIntersections.IsIrreducible, OAI.HarmonicArtin.ParabolicIntersections.VisualVertex, OAI.HarmonicArtin.Artin
- theorem
OAI.HarmonicArtin.ParabolicIntersections.visual_factor_weaklyMalnormalline 63Source documentation
Each vertex factor of a visual splitting is weakly malnormal.
theorem visual_factor_weaklyMalnormal (hIrred : IsIrreducible M) (b : Bool) : WeaklyMalnormal (artinParabolic M (visualSide Y Z b)) := by …Mentions: OAI.HarmonicArtin.ParabolicIntersections.IsIrreducible, OAI.HarmonicArtin.ParabolicIntersections.WeaklyMalnormal, OAI.HarmonicArtin.artinParabolic, OAI.HarmonicArtin.ParabolicIntersections.visualSide
- theorem
OAI.HarmonicArtin.ParabolicIntersections.visual_subgroup_weaklyMalnormalline 75Source documentation
Any parabolic lying in a vertex factor inherits its weak malnormality.
theorem visual_subgroup_weaklyMalnormal (hIrred : IsIrreducible M) (b : Bool) (P : Subgroup (Artin M)) (hP : P≤artinParabolic M (visualSide Y Z b)) : WeaklyMalnormal P := …Mentions: OAI.HarmonicArtin.ParabolicIntersections.IsIrreducible, OAI.HarmonicArtin.Artin, OAI.HarmonicArtin.artinParabolic, OAI.HarmonicArtin.ParabolicIntersections.visualSide, OAI.HarmonicArtin.ParabolicIntersections.WeaklyMalnormal