The embedded desingularization functor in every dimension #
The all-dimensions embedded desingularization functor BEDanFamStarOfInput bmod hbmod: the functors
bedanFamOfInput bmod n of Hironaka/Resolution/Analytic/Wlo09/Basic.lean in every dimension n,
together with the commutation with closed embeddings of the ambient manifold that clause (4) of
[Wlo09, Theorem 2.0.2] requires, which is proved from the corresponding commutation hbmod of the
modified marked resolution bmod.
AnalyticFamilyFunctor.CommutesWithLocalIsos.restrictDomainandAnalyticFamilyFunctor.CommutesWithClosedEmbeddingsOfEmptyDivisorFam.restrictDomain: the two functoriality predicates descend from a family functorBon a classDomto any family functorB₀on a sub-classDom₀ ⊆ Domthat agrees withBthere; the triples and their class proofs are hypotheses of both predicates, so the descent is the transport of the agreements.bedanFamOfInput_commutesWithClosedEmbeddings bmod hbmod n s: the embedded desingularization in dimensionncommutes with closed embeddings of empty divisor through the one in dimensionn − s, the restriction ofhbmod n sto the classDomBEDan ⊆ BMOClass 1(DomBEDan.bmoClass_one).BEDanFamStarOfInput bmod hbmod : BEDanFamStar 𝕜: the functors of every dimension with the closed-embedding field;BEDanFamStarOfInput_fam: the dimension-wise functors unfolded (rfl).
Why the field holds. Resolving (M', I', ∅, 1) for a closed embedding M ↪ M' of ambient
manifolds is equivalent to resolving (M, I, ∅, 1) [Wlo09, §7.1]: the coordinates u₁, …, u_k of
M in M' define tangent directions of I', the algorithm passes to the hypersurface V(u₁) and
repeats k times (this is clause (3) of [Wlo09, Theorem 3.5.1] for the canonical resolution of
marked ideals). That commutation is a property of the modified marked resolution bmod, taken here
as the hypothesis hbmod (proved for the concrete resolution in
Hironaka/Resolution/Analytic/Wlo09/Concrete.lean). The embedded desingularization is the
restriction of that resolution to the class DomBEDan, so the commutation descends: the predicate's
triples and their class proofs are its own hypotheses, and bedanFamOfInput bmod n agrees with
(bmod n).functor on the class by definition.
The predicate CommutesWithLocalIsos descends to a sub-class: if B commutes with local
analytic isomorphisms on Dom and B₀ on Dom₀ ⊆ Dom agrees with B there, then B₀ commutes
with local analytic isomorphisms. Not in the sources; bookkeeping.
The predicate CommutesWithClosedEmbeddingsOfEmptyDivisorFam descends to sub-classes: if B
commutes with closed embeddings of empty divisor through B' and B₀, B₀' agree with B, B'
on the sub-classes Dom₀ ⊆ Dom, Dom₀' ⊆ Dom', then B₀ commutes with closed embeddings of empty
divisor through B₀'. Not in the sources; bookkeeping.
The embedded desingularization in dimension n commutes with closed embeddings of empty
divisor through the one in dimension n − s (the embeddings of ambient manifolds in clause (4) of
[Wlo09, Theorem 2.0.2]; [Wlo09, §7.1]): the restriction to the class DomBEDan ⊆ BMOClass 1
(DomBEDan.bmoClass_one) of the commutation hbmod n s of the modified marked resolution. The
larger functors (bmod n).functor, (bmod (n - s)).functor are passed by name, since the
predicate's hypothesis alone does not determine them for the unifier.
The embedded desingularization functor in every dimension ([Wlo09, Theorem 2.0.2], with the
commutation with embeddings of ambient manifolds of its clause (4), [Wlo09, §7.1] and
[Wlo09, Theorem 3.5.1 (3)]), from a modified marked resolution bmod : ∀ n, BMOmodFam 𝕜 n in every
dimension and its commutation hbmod with closed embeddings of empty divisor. The dimension-wise
functors are bedanFamOfInput bmod n by definition, and the closed-embedding field is
bedanFamOfInput_commutesWithClosedEmbeddings, the restriction of hbmod n s to the class
DomBEDan ⊆ BMOClass 1.
Equations
- Hironaka.Manifold.BEDanFamStarOfInput 𝕜 bmod hbmod = { fam := fun (n : ℕ) => Hironaka.Manifold.bedanFamOfInput 𝕜 bmod n, closedEmbedding := ⋯ }
Instances For
The dimension-wise functors of BEDanFamStarOfInput, unfolded (rfl).