OAI/Algebra/Finitistic/Rectification/TensorProjection.lean
7 declarations, 0 contain sorry, 0 declared as axioms
- def
OAI.LittleFinitistic.TensorProjection.rightMapline 15Source documentation
Tensor a k-linear map with the identity while retaining the actual right B-action.
def rightMap (f : M →ₗ[k] M') : (M ⊗[k] N) →ₗ[Bᵐᵒᵖ] (M' ⊗[k] N) where …
- theorem
OAI.LittleFinitistic.TensorProjection.rightMap_tmulline 22 - def
OAI.LittleFinitistic.TensorProjection.rightCongrline 26Source documentation
Transport a first-factor vector-space equivalence as an actual right-module equivalence.
def rightCongr (e : M ≃ₗ[k] M') : (M ⊗[k] N) ≃ₗ[Bᵐᵒᵖ] (M' ⊗[k] N) where …
- def
OAI.LittleFinitistic.TensorProjection.fixedline 41Source documentation
The actual fixed submodule for a projector on the first tensor factor.
def fixed : Submodule Bᵐᵒᵖ (M ⊗[k] N) := (rightMap (B := B) p - LinearMap.id).ker
- theorem
OAI.LittleFinitistic.TensorProjection.mem_fixedline 43 - theorem
OAI.LittleFinitistic.TensorProjection.range_fixedline 46 - def
OAI.LittleFinitistic.TensorProjection.imageTensorEquivline 52Source documentation
The eigenspace e(M tensor N) is exactly (eM) tensor N as a right module.
def imageTensorEquiv (hp : p.comp p = p) : (p.range ⊗[k] N) ≃ₗ[Bᵐᵒᵖ] fixed (B := B) (N := N) p where …