Lemma 102: indifference to empty boundary members #
The analytic functors are required to be indifferent to empty boundary members
(AnalyticBlowUpSequenceAssignment.IndifferentToEmptyMembers; the counterpart for
boundary members of the empty blow-up convention [Kol07, 32]): deleting empty members of the
boundary along an order
embedding of index sets does not change the value. For BDan, the analytic BD_{n,m,·} of
[Kol07, Lemma 102], the value at a kept member e i of E equals the value at the member i of
the smaller boundary F'.
The first centre and the transform of the member depend only on the hypersurface
E^j = E^{e i} = F'^i itself (Zminus1_eq_of_hyp_eq, transformS_eq_transformSOf, read through
the parametrized core of BDOf.lean); the two restricted triples differ only in the index set of
their boundary, and the indifference of the input functor absorbs the difference: the restriction
of E - E^{e i} to S_0 embeds the restriction of F' - F'^i along e, with the members
matched and empty outside the range.
BDan.withBoundary— the triple with its boundary replaced.BDan.Zminus1_eq_of_hyp_eq,BDan.transformS_eq_transformSOf— the data ate iand ati.BDan.core_indifferentToEmptyMembers— the clause for the core at the marks.BDan_indifferentToEmptyMembers— the clause forBDan, tuning keeping the boundary.
The triple T with its boundary replaced by the family F' with simple normal crossings.
Equations
- Hironaka.Manifold.BDan.withBoundary T F' hsnc' = { I := T.I, isNonzeroEverywhere := ⋯, F := F', isSnc := hsnc' }
Instances For
The first centre at the member e i of E is the first centre at the member i of F'.
The transform of the member e i of E is the transform of the member i of F' (over the
first centre at e i).
Indifference to empty boundary members for the core at the mark s: the core at the member
e i of E is the core at the member i of F'. The first centre and the transform of the
member agree, and the input functor is indifferent to the empty members of the restricted
boundary: the restriction of E - E^{e i} to S_0 embeds that of F' - F'^i along e, with
matched members and empty members outside the range.
BD_{n,m,·} is indifferent to empty boundary members (the counterpart for boundary
members of the empty blow-up convention [Kol07, 32]): for a boundary F' with simple normal
crossings embedding
order-preservingly into E along e, with the members matched and empty outside the range, the
value at the kept member e i equals the value at i for the triple with boundary F'. It is the
clause for the core at the tuned triple, tuning keeping the boundary.