OAI/GroupTheory/PolycyclicRecognition/Finiteness/HomogeneousRepresentationCochains.lean
13 declarations, 0 contain sorry, 0 declared as axioms
Controlled cochains as maps from the standard resolution
The coefficient at the identity of an equivariant group-ring-valued map recovers the scalar cochain. Conversely diagonal translation reconstructs that equivariant map, with finite support supplied by controlled-support estimates.
- def
OAI.PolycyclicRecognition.homogeneousGroupRingValueline 19 - theorem
OAI.PolycyclicRecognition.homogeneousGroupRingValue_coeffline 22 - theorem
OAI.PolycyclicRecognition.homogeneousGroupRingValue_covarianceline 26 - def
OAI.PolycyclicRecognition.homogeneousGroupRingLinearline 34 - theorem
OAI.PolycyclicRecognition.homogeneousGroupRingLinear_singleline 39 - def
OAI.PolycyclicRecognition.homogeneousRepresentationCochainline 45Source documentation
The reconstructed values give an actual morphism of group representations.
def homogeneousRepresentationCochain (c : controlledCochains R G n) : (Rep.standardComplex R G).X n ⟶ Rep.leftRegular R G := … - theorem
OAI.PolycyclicRecognition.homogeneousRepresentationCochain_single_coeffline 61 - theorem
OAI.PolycyclicRecognition.representationCochain_translateline 67 - theorem
OAI.PolycyclicRecognition.representationCochain_controlledline 83Source documentation
Evaluation at the identity has controlled support for every equivariant map from the homogeneous resolution.
theorem representationCochain_controlled (F : (Rep.standardComplex R G).X n ⟶ Rep.leftRegular R G) : (fun x => (F.hom (MonoidAlgebra.single x 1)).coeff 1) ∈ controlledCochains R G n := by … - def
OAI.PolycyclicRecognition.representationControlledCochainline 103Source documentation
Scalar coefficient extraction, with its support obligation proved.
def representationControlledCochain (F : (Rep.standardComplex R G).X n ⟶ Rep.leftRegular R G) : controlledCochains R G n := … - theorem
OAI.PolycyclicRecognition.representationControlledCochain_homogeneousline 109 - theorem
OAI.PolycyclicRecognition.homogeneousRepresentationCochain_controlledline 116 - def
OAI.PolycyclicRecognition.homogeneousRepresentationCochainEquivline 136Source documentation
Controlled scalar cochains are exactly the equivariant cochains with coefficients in the left regular group ring.
def homogeneousRepresentationCochainEquiv : controlledCochains R G n ≃ₗ[R] ((Rep.standardComplex R G).X n ⟶ Rep.leftRegular R G) where …