Symmetric period comparison on a rigid genus-two wedge #
WedgeKGeneralConverse proves the period comparison after choosing an order
on the two factors. This file removes that bookkeeping hypothesis by
commuting the vertex wedge and swapping the marked vertices in the other
case.
theorem
Bananas.factor_torsionOrders_eq_of_vertexWedge_opposite_kGeneral_symmetric
{G H : CFGraph}
(x : G.V)
(y : H.V)
(u : G.V)
(v : H.V)
(a b k : ℕ)
(hG : Utilities.PointedGenusOneRigid G x)
(hH : Utilities.PointedGenusOneRigid H y)
(hu : u ≠ x)
(hv : v ≠ y)
(hA : IsTorsionOrder (mark G u x) a)
(hB : IsTorsionOrder (mark H y v) b)
(hWCut : Utilities.TwoEdgeCutCondition (Utilities.vertexWedge G H x y))
(hWRigid :
¬linearEquiv (Utilities.vertexWedge G H x y) (oneChip (Sum.inl u) + oneChip (Utilities.wedgeRightVertex G H x y v))
(canonicalDivisor (Utilities.vertexWedge G H x y)))
(hK : KGeneralTransmission (mark (Utilities.vertexWedge G H x y) (Sum.inl u) (Utilities.wedgeRightVertex G H x y v)) k)
:
The period comparison on an opposite-side rigid wedge is symmetric in the
two factors: distinct factor marks force their exact torsion orders to agree
under k-general transmission.