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Hironaka.Resolution.Analytic.Wlo09.Basic

The analytic embedded desingularization as the modified marked resolution on reduced subspaces #

Włodarczyk's embedded desingularization of a closed analytic subspace Y ⊆ M [Wlo09, Theorem 2.0.2] is obtained by running the resolution algorithm for the marked ideal (M, 𝓘_Y, ∅, 1) in a modified form (the proof of [Wlo09, Theorem 7.4.1]): the algorithm is stopped as soon as the controlled transform is the ideal of a smooth hypersurface of maximal contact, and it ends with the ideal of a smooth submanifold transversal to the exceptional divisors. The structure BMOmodFam 𝕜 n packages such a modified marked resolution in dimension n on the class of marked triples of mark 1: its functor is a compatible family of blow-up sequences per relatively compact open, and its fields record the order clause (isOfOrderGe), the containment of the centres in the support (center_mem_support), the shape of the final controlled transform (output_isSmoothSubmanifoldIdeal) and the stop rule (stopped_never_blownUp).

This module defines the embedded desingularization functor in dimension n as that resolution restricted to the class DomBEDan of triples with empty boundary and reduced ideal: Y is recovered from 𝓘_Y, and on this class the modified marked resolution is Włodarczyk's embedded desingularization itself. Włodarczyk's algebraic version [Wlo05, Theorem 4.7.1] has in addition an outer loop that isolates the components of the strict transform one codimension at a time; that loop serves the algebraic ordering of the algorithm and is not part of the analytic construction, so it is not transcribed. The compatible-family data (seqOn U hU, noEmptyCenters, compat) are inherited from the modified marked resolution; the final step of Włodarczyk's proof, blowing up the components of the final support that are not strict transforms of components of Y, is void for reduced Y.

The clauses of [Wlo09, Theorem 2.0.2] for this functor are proved in the other modules of Hironaka/Resolution/Analytic/Wlo09/ from the fields of BMOmodFam, per relatively compact open, and assembled in Hironaka/Resolution/Analytic/Wlo09/Assembly.lean.

theorem Hironaka.Manifold.DomBEDan.bmoClass_one (𝕜 : Type) [RCLike 𝕜] {n : ℕ} {M : AnalyticManifold 𝕜 (Fin n → 𝕜)} {T : Manifold.AnalyticTriple (ContinuousLinearEquiv.refl 𝕜 (Fin n → 𝕜)) M} (hT : DomBEDan 𝕜 T) :

A triple of the class DomBEDan is a marked triple of mark 1 (BMOClass 1 of OrderReduction/MarkedData.lean): 1 ≤ 1, and the boundary has no members at all (IsEmpty T.F.ι), so finitely many nonempty ones.

def Hironaka.Manifold.bedanFamOfInput (𝕜 : Type) [RCLike 𝕜] (bmod : (n : ℕ) → BMOmodFam 𝕜 n) (n : ℕ) :
BEDanFam 𝕜 n

The embedded desingularization functor in dimension n ([Wlo09, Theorem 2.0.2], constructed as in the proof of [Wlo09, Theorem 7.4.1]): the modified marked resolution bmod n restricted to the class DomBEDan of triples with empty boundary and reduced ideal.

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Instances For
    theorem Hironaka.Manifold.bedanFamOfInput_fam (𝕜 : Type) [RCLike 𝕜] (bmod : (n : ℕ) → BMOmodFam 𝕜 n) (n : ℕ) {M : AnalyticManifold 𝕜 (Fin n → 𝕜)} (T : Manifold.AnalyticTriple (ContinuousLinearEquiv.refl 𝕜 (Fin n → 𝕜)) M) (hT : DomBEDan 𝕜 T) :
    (bedanFamOfInput 𝕜 bmod n).fam T hT = (bmod n).functor.fam T ⋯

    The value of the embedded desingularization functor, unfolded (rfl).