OAI/GroupTheory/Thompson/AffineTransport.lean
3 declarations, 0 contain sorry, 0 declared as axioms
Simultaneous affine transport of two separated basic intervals
Each of the three complementary gaps is partitioned and equalized separately. Consequently the selected source and target cells occupy matching positions in the two full ordered partitions. The interpolation theorem constructs an actual increasing dyadic PL homeomorphism on those partitions.
- theorem
OAI.ThompsonNonamenability.forall₂_after_prefixline 22 - theorem
OAI.ThompsonNonamenability.exists_pair_transport_of_partitionsline 31Source documentation
The selected positions are preserved because the three gap lengths are equalized independently. All partition data will be constructed below.
private theorem exists_pair_transport_of_partitions (I J I' J' : BasicInterval) (P₀ : DyadicGapPartition 0 I.left) (Q₀ : DyadicGapPartition 0 I'.left) (P₁ : DyadicGapPartition I.right J.left) (Q₁ : DyadicGapPartition I'.right J'.left) (P₂ : DyadicGapPartition J.right 1) (Q₂ : DyadicGapPartition J'.right 1) (hlen₀ : P₀.cells.length = Q₀.cells.length) (hlen₁ : P₁.cells.length = Q₁.cells.length) (hlen₂ : P₂.cells.length = Q₂.cells.length) : ∃ h : F, CarriesAffinely h I I' ∧ CarriesAffinely h J J' := by …Mentions: OAI.ThompsonNonamenability.BasicInterval, OAI.ThompsonNonamenability.DyadicGapPartition, OAI.ThompsonNonamenability.F, OAI.ThompsonNonamenability.CarriesAffinely
- theorem
OAI.ThompsonNonamenability.exists_affine_pair_transportline 62Source documentation
Two strictly separated internal basic intervals can simultaneously be carried onto any other such pair by an actual element of standard Thompson F.
theorem exists_affine_pair_transport {I J I' J' : BasicInterval} (hI : I.Internal) (hJ : J.Internal) (hI' : I'.Internal) (hJ' : J'.Internal) (hIJ : I.Before J) (hIJ' : I'.Before J') : ∃ h : F, CarriesAffinely h I I' ∧ CarriesAffinely h J J' := by …Mentions: OAI.ThompsonNonamenability.BasicInterval, OAI.ThompsonNonamenability.F, OAI.ThompsonNonamenability.CarriesAffinely