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Hironaka.Resolution.Analytic.OrderReduction.BDFamIndiff

Lemma 102 in the compatible-family form: indifference to empty boundary members #

The value of BD_{n,m,j} on a relatively compact open does not see empty members of the boundary (BDanFam_indifferentToEmptyMembers; the counterpart of BDan_indifferentToEmptyMembers of BDIndiff.lean; for boundary members the counterpart of Kollár's convention that empty blow-ups are ignored, [Kol07, 32]): when F' is E with empty members deleted along an order embedding e, the value at the member e i of E equals the value at the member i of F', on every open. As in BDIndiff.lean, the core on an open is first written over an arbitrary centre and transform (coreFamOn_eq_of_eq, the counterpart of core_eq_of_eq; the centre and the transform at e i and at i agree as sets by Zminus1_eq_of_hyp_eq and transformS_eq_transformSOf, so both sides live on the same data), and then the input family's own indifference identifies the two values read at the trace of π_{-1}^{-1}(U): the restricted boundary of E - E^{e i} embeds that of F' - F'^i along e, with empty members outside the range.

This is the indifferentToEmptyMembers field of Lemma 102's family data bdanFamDataOfInput in BOanFamOfInput.lean.

The core on an open over an arbitrary centre and transform #

theorem Hironaka.Manifold.BDan.coreFamOn_eq_of_eq {𝕜 : Type} [RCLike 𝕜] {E : Type u_1} [NormedAddCommGroup E] [NormedSpace 𝕜 E] [FiniteDimensional 𝕜 E] {n : ℕ} {ψ₀ : E ≃L[𝕜] Fin n → 𝕜} {M : AnalyticManifold 𝕜 E} (T : Manifold.AnalyticTriple ψ₀ M) (s : ℕ) (j : T.F.ι) {Z : Set M.carrier} (hZ : Manifold.IsClosedSubmanifold ψ₀ Z 1) {S' : Set (Manifold.blowUp ψ₀ hZ).carrier} (hS' : Manifold.IsClosedSubmanifold ψ₀ S' 1) (inp : BMOanFam 𝕜 (n - 1) s) (hT : BDClass s T) (hZeq : Z = BD.Zminus1 T.I s (T.F.hyp j)) (hSeq : S' = transformSOf T j hZ) (U : TopologicalSpace.Opens M.carrier) (hU : IsCompact (closure ↑U)) :

The core on an open (coreFamOn, BDFam.lean) read over any closed hypersurface Z = Z_{-1} and any closed hypersurface S' = S_0 of its blowing-up (a substitution; the counterpart of core_eq_of_eq in BDOf.lean).

Indifference #

theorem Hironaka.Manifold.BDan.coreFamOn_indifferentToEmptyMembers {𝕜 : Type} [RCLike 𝕜] {E : Type u_1} [NormedAddCommGroup E] [NormedSpace 𝕜 E] [FiniteDimensional 𝕜 E] {n : ℕ} {ψ₀ : E ≃L[𝕜] Fin n → 𝕜} {M : AnalyticManifold 𝕜 E} (T : Manifold.AnalyticTriple ψ₀ M) (s : ℕ) (F' : Manifold.HypersurfaceFamily M.carrier) (hsnc' : Manifold.HypersurfaceFamily.IsSnc ψ₀ F') (e : F'.ι ↪o T.F.ι) (he : ∀ (i : F'.ι), T.F.hyp (e i) = F'.hyp i) (i : F'.ι) (he' : ∀ b ∉ Set.range ⇑e, T.F.hyp b = ∅) (inp : BMOanFam 𝕜 (n - 1) s) (hT : BDClass s T) (hT₂ : BDClass s (withBoundary T F' hsnc')) (U : TopologicalSpace.Opens M.carrier) (hU : IsCompact (closure ↑U)) :
coreFamOn T s (e i) inp hT U hU = coreFamOn (withBoundary T F' hsnc') s i inp hT₂ U hU

The core on an open is indifferent to empty boundary members: the core at the member e i of E is the core at the member i of F', when F' is E with the empty members outside the range of e deleted. The first centre and the transform are the same sets, and the input family is indifferent, on the trace of π_{-1}^{-1}(U), to the empty members of the restricted boundary (E - E^{e i})|_{S_0}, which embeds (F' - F'^i)|_{S_0} along e.

theorem Hironaka.Manifold.BDanFam_indifferentToEmptyMembers {𝕜 : Type} [RCLike 𝕜] {E : Type u_1} [NormedAddCommGroup E] [NormedSpace 𝕜 E] [FiniteDimensional 𝕜 E] {n : ℕ} {ψ₀ : E ≃L[𝕜] Fin n → 𝕜} {M : AnalyticManifold 𝕜 E} {m : ℕ} (inp : BMOanFam 𝕜 (n - 1) (IsLocalRing.tuningParam m)) (T : Manifold.AnalyticTriple ψ₀ M) (F' : Manifold.HypersurfaceFamily M.carrier) (hsnc' : Manifold.HypersurfaceFamily.IsSnc ψ₀ F') (e : F'.ι ↪o T.F.ι) (he : ∀ (i : F'.ι), T.F.hyp (e i) = F'.hyp i) (he' : ∀ b ∉ Set.range ⇑e, T.F.hyp b = ∅) (hT : Manifold.AnalyticTriple.BOClass m T) (hT' : Manifold.AnalyticTriple.BOClass m { I := T.I, isNonzeroEverywhere := ⋯, F := F', isSnc := hsnc' }) (i : F'.ι) (U : TopologicalSpace.Opens M.carrier) (hU : IsCompact (closure ↑U)) :
BDanFam m inp T hT (e i) U hU = BDanFam m inp { I := T.I, isNonzeroEverywhere := ⋯, F := F', isSnc := hsnc' } hT' i U hU

The value of BD_{n,m,·} on every relatively compact open is indifferent to empty boundary members: when F' is E with the empty members outside the range of the order embedding e deleted, the value at the member e i of E equals the value at the member i of F'. This is coreFamOn_indifferentToEmptyMembers at the tuned triple (the tuning keeps the boundary).