Official module-category surplus and numerical count estimates #
theorem
MagnitudeConjecture.RightModule.FiniteIndecomposableSkeleton.ambientARSurplus_eq_counts
{k A : Type u}
[Field k]
[IsAlgClosed k]
[Ring A]
[Algebra k A]
[FiniteDimensional k A]
[IsNoetherianRing Aᵐᵒᵖ]
(S : FiniteIndecomposableSkeleton k A)
:
S.ambientARSurplus = 2 * ↑S.n - ARCount.arrowCount (FiniteTauMatrix.arrowMultiplicity S.finiteTauCategoryData.toFiniteRightTauCategoryData) - 2 * ↑S.simpleCount
The official ambient surplus uses the literal indecomposable and simple counts and the official arrow multiplicities.
theorem
MagnitudeConjecture.RightModule.FiniteIndecomposableSkeleton.ambientARSurplus_error_of_counts
{k A B : Type u}
[Field k]
[IsAlgClosed k]
[Ring A]
[Algebra k A]
[FiniteDimensional k A]
[IsNoetherianRing Aᵐᵒᵖ]
[Ring B]
[Algebra k B]
[FiniteDimensional k B]
[IsNoetherianRing Bᵐᵒᵖ]
(S : FiniteIndecomposableSkeleton k A)
(T : FiniteIndecomposableSkeleton k B)
(m : ℕ)
(W C : ℤ)
(hN : ↑T.n = ↑S.n * (↑m + 1) - W)
(ha :
|ARCount.arrowCount (FiniteTauMatrix.arrowMultiplicity T.finiteTauCategoryData.toFiniteRightTauCategoryData) - (↑m + 1) * ARCount.arrowCount (FiniteTauMatrix.arrowMultiplicity S.finiteTauCategoryData.toFiniteRightTauCategoryData)| ≤ C)
(hp : T.simpleCount = S.simpleCount * (m + 1))
:
|T.ambientARSurplus - (↑m + 1) * S.ambientARSurplus| ≤ 2 * |W| + C
Exact indecomposable and simple counts and an arrow bound control the official surplus of a second finite module skeleton.