The monomial predicate along the assembly of the value #
BlowUpSequence.PullbackIsMonomialAtLast L F I: at every point x of the last stage of L, the
pull-back of I along the composite blow-down is a monomial in the vanishing ideals of finitely
many members of the final total transform of F through x — the chart-free monomial clause of
Kollár's explicit formula [Kol07, 72], as a predicate on a list of centres. It is transported along
the constructions that assemble the principalization:
cons(pullbackIsMonomialAtLast_cons): the head blow-up pullsIandFback, the tail carries the predicate (cons_totalTransformSeqFrom_last,stageMapAux_cons_succ);concat(pullbackIsMonomialAtLast_concat, by induction throughcons): the predicate for the appended list with the boundary and the pulled-back ideal at the junction gives it for the concatenation — the shrink-and-append step is aconcatof a pulled-back list;eraseEmpty(pullbackIsMonomialAtLast_eraseEmpty): along the diffeomorphismeraseEmptyLastof the last stages (the deletion of the empty blow-ups, [Kol07, 32]) the composites agree (stageMap_last_eraseEmptyLast), the boundary members correspond with the members of the list's boundary outside the range of the empty ones (boundaryCorr_eraseEmpty), and the vanishing ideals transport along the bijective germ map (vanishingStalk_preimage_diffeomorph);- the order clause
ord I_r < 1of the input ([Kol07, Theorem 107 (1)]) along the pull-back of a list by a local isomorphism (ord_markedTransformSeq_pullback_last_lt_one, viamarkedTransformSeqAux_pullback):ord < 1is "the stalk is the unit ideal", which pulls back.
Used for the monomial clause at general mark (MonomialSeqMark.lean).
Order < 1 at a point means the stalk is the unit ideal (ord_eq_zero_iff).
Order < 1 pulls back along any analytic map (the unit stalk maps to the unit ideal).
The chart-free reading of Kollár's formula [Kol07, 72] as a predicate on a list: at every point
x of the last stage, the pull-back of I along the composite blow-down is a monomial in the
vanishing ideals of finitely many members of the final total transform of F through x.
Equations
- One or more equations did not get rendered due to their size.
Instances For
The composite blow-down of cons hY rest is the head blow-up after the tail's composite, as
ideal-sheaf pull-backs.
The predicate for cons hY rest from the predicate for the tail with the pulled-back boundary
and ideal.
The predicate for a concatenation from the predicate for the appended list with the boundary and the pulled-back ideal at the junction.
The predicate is preserved by the deletion of the empty blow-ups ([Kol07, 32]): along the
diffeomorphism eraseEmptyLast of the last stages the composites agree and the boundary members
correspond (boundaryCorr_eraseEmpty), the vanishing ideals transporting along the bijective
germ map.
The order clause of [Kol07, Theorem 107 (1)] along the pull-back of a list by a local analytic
isomorphism: the last marked transform of the pulled-back list is the pull-back of the last marked
transform (markedTransformSeqAux_pullback), so ord < 1 — the unit stalk — pulls back.