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Hironaka.Resolution.Algebraic.Stage.DimFreeTheorems

Theorems 68 and 69 for the dimension-free functors over a base stage #

[Kol07, Theorems 68 and 69] for dimFreeBO base m k and dimFreeBMO base m k (Hironaka.Resolution.Algebraic.Stage.DimFree), over an ARBITRARY base stage base : OrderReductionStage 0; Hironaka.Resolution.Algebraic.Stage.Theorem68 instantiates them at stage0 for BO_m and BMO_m, and the proofs of Main Theorems II and II(N), of Theorem 35 and of the embedded desingularization read the clauses from here. Every proof is one pattern:

Claim 71.2 is Hironaka.Resolution.Algebraic.Stage.ClosedEmbeddingGeneral.

Coherence at the maximum #

theorem Hironaka.Stage.dimFreeBO_seq_eq_tower (base : OrderReductionStage 0) (m : ℕ) {k : Type u} [Field k] [CharZero k] (n : ℕ) (T : AlgebraicGeometry.Triple k) (hT : AlgebraicGeometry.Triple.BOClassFree m T) (hT' : AlgebraicGeometry.Triple.BOClass n m T) :
(dimFreeBO base m k).seq T hT = (((tower base n).bo m).functor k).seq T hT'

The dimension-free unmarked functor agrees with the tower's BO_{n, m} at every triple of the stage-n class — both stages meet at max T.dim n through tower_bo_coherent (any n ≥ dim X gives the same sequence).

theorem Hironaka.Stage.dimFreeBMO_seq_eq_tower (base : OrderReductionStage 0) (m : ℕ) {k : Type u} [Field k] [CharZero k] (n : ℕ) (T : MarkedTriple k) (hT : MarkedTriple.BMOClassFree m T) (hT' : MarkedTriple.BMOClass n m T) :
(dimFreeBMO base m k).seq T hT = (((tower base n).bmo m).functor k).seq T hT'

The marked form: the dimension-free marked functor agrees with the tower's BMO_{n, m} at every marked triple of the stage-n class.

Clause (1) of Theorems 68 and 69 #

[Kol07, Theorem 68 (1)]: max-ord I_r < m — the stage functor's clause (1) (Theorem 103 (1)) at stage T.dim.

theorem Hironaka.Stage.dimFreeBMO_maxOrd_lt (base : OrderReductionStage 0) (m : ℕ) {k : Type u} [Field k] [CharZero k] (T : MarkedTriple k) (hT : MarkedTriple.BMOClassFree m T) :
(((dimFreeBMO base m k).seq T hT).markedTransformSeq T.I T.m (Fin.last ((dimFreeBMO base m k).seq T hT).length)).maxOrd < ↑m

[Kol07, Theorem 69 (1)]: max-ord I_r < m for the marked functor (Theorem 107 (1)).

Clause (2) of Theorems 68 and 69 #

[Kol07, Theorem 68 (2)], functoriality for smooth morphisms [Kol07, 34.1] of ANY relative dimension: both triples of a pull-back situation T' → T lie in the class of N := max T.dim T'.dim; coherence moves both values to stage N, whose field is 34.1.

theorem Hironaka.Stage.dimFreeBO_commutesWithBaseChange (base : OrderReductionStage 0) (m : ℕ) {k : Type u} [Field k] [CharZero k] {L : Type u} [Field L] [CharZero L] (σ : k →+* L) :
(dimFreeBO base m k).CommutesWithBaseChange (dimFreeBO base m L) σ

[Kol07, Theorem 68 (2)], change of fields [Kol07, 34.2]: the base-change triple T' over L and T over k lie in the class of N := max T.dim T'.dim; the stage-N field is 34.2.

[Kol07, Theorem 69 (2)], functoriality for smooth morphisms [Kol07, 34.1], for the marked functor.

theorem Hironaka.Stage.dimFreeBMO_commutesWithBaseChange (base : OrderReductionStage 0) (m : ℕ) {k : Type u} [Field k] [CharZero k] {L : Type u} [Field L] [CharZero L] (σ : k →+* L) :

[Kol07, Theorem 69 (2)], change of fields [Kol07, 34.2], for the marked functor.

Every stage of the tower's unmarked family is indifferent to empty boundary members — boOfBMO_indifferentToEmptyMembers at stages n + 1, and at stage 0 both values are nil (the dimension-0 lemma; BOData has no indifference field, so the base contributes nothing but its class).

The dimension-free marked functor is indifferent to empty boundary members — the two triples share the ambient scheme, and both lie in the class of the common stage max, whose field is the indifference.

The dimension-free unmarked functor is indifferent to empty boundary members, from tower_bo_indifferentToEmptyMembers at the common stage.

Claim 71.1 #

theorem Hironaka.Stage.tower_bmo_eq_bo_of_maxOrd (base : OrderReductionStage 0) (m : ℕ) {k : Type u} [Field k] [CharZero k] (n : ℕ) (T : AlgebraicGeometry.Triple k) (hT : AlgebraicGeometry.Triple.BOClass n m T) (hE : IsEmpty T.E.ι) (hmax : T.I.maxOrd = ↑m) :
(((tower base n).bmo m).functor k).seq { toTriple := T, m := m } ⋯ = (((tower base n).bo m).functor k).seq T hT

[Kol07, Claim 71.1] at every stage of the tower ([Kol07, 108]: "(71.1) is the same as (107.3)"): for E = ∅ and max-ord I = m, the marked functor at (X, I, m, ∅) equals the unmarked one at (X, I, ∅) — eq_BO_of_maxOrd at stages n + 1 (where the tower's functors ARE those of the assembly of Theorem 107, tower_succ_bmo/tower_succ_bo by rfl), and both nil at stage 0.

theorem Hironaka.Stage.dimFree_claim71_1 (base : OrderReductionStage 0) (m : ℕ) {k : Type u} [Field k] [CharZero k] (T : AlgebraicGeometry.Triple k) (hE : IsEmpty T.E.ι) (hm : 1 ≤ m) (hmax : T.I.maxOrd = ↑m) :
(dimFreeBMO base m k).seq { toTriple := T, m := m } ⋯ = (dimFreeBO base m k).seq T ⋯

[Kol07, Claim 71.1], dimension-free: BMO_m(X, I, m, ∅) = BO_m(X, I, ∅) when max-ord I = m — tower_bmo_eq_bo_of_maxOrd at the stage T.dim both functors read.