Documentation

Hironaka.Resolution.Analytic.OrderReduction.Modified.StepATransport

The rounds on the nonmonomial part: transport of one link of the descent #

The second condition of [Kol07, 34.1] and the compatibility [Wlo09, Theorem 2.0.3 (4)] for one link of the descent of the rounds on the nonmonomial part ([Kol07, 111, Step 1]; [Wlo09, Theorem 7.4.1]): along a local analytic isomorphism h : N → M carrying an open W' ⊆ N into W ⊆ M, a descent state over W' for the pulled-back triple and a descent state over W at the same bound d, whose lists agree up to empty blow-ups after pulling back, keep that relation through one link (descentLink_rel; smaller opens V' ⊆ W', V ⊆ W with h(V') ⊆ V). This is ChainState.link_rel with the family read at the nonmonomial triple of the induced triple (nonmonomialFunctor): the list algebra is BlowUpSequence.shrinkAppend_eraseEmpty_pullback unchanged; the two appended values of the round are compared by AnalyticFamilyFunctor.inducedValue_rel for that functor, whose class proofs are the invariants of the descent (BState.nonmonomialClass), transported to the cleaned lists by nonmonomialClass_induced_eraseEmpty (the nonmonomial part is indifferent to empty members and commutes with pull-back: NonmonomialIndiff.lean, NonmonomialComap).

The relation is the inductive step of the compatibility of the values and of the independence of the value from the chain and the outer open; the alignment of two descents of different lengths (the empty links above the smaller bound) is StepAAlign.lean.

The class of the induced triple of the cleaned list #

The invariant of the descent passes to the cleaned list ([Kol07, 32] and its counterpart for boundary members): the induced triple of the list is the induced triple of the cleaned list pulled back along eraseEmptyLast, up to empty boundary members (induced_eq_pullback_induced_eraseEmpty); the nonmonomial triple ignores the empty members (nonmonomialClass_of_isEmptyExtension) and commutes with the pull-back (NonmonomialComap); and the order bound and the finiteness of the nonempty members transport along the diffeomorphism (ord_pullback_of_isLocalDiffeomorphAt).