Feeding the geometric Corvaja--Zannier estimate into a Markoff move #
This module connects the weighted torsion-intersection bound to the already completed middle-game order-escape chain. The actual weighted trace curve's admissibility is proved from its Markoff coefficients.
Given those premises, Lean returns a natural iterate of the Markoff rotation with strictly larger neighboring rotation order. No independent weighted-finset estimate remains between the cited curve theorem and the dynamical conclusion.
theorem
BGS.Markoff.exists_iterate_with_larger_secondRotationOrder_of_weightedTraceBound
(p : ℕ)
[Fact (Nat.Prime p)]
[Fintype (quadraticFiniteField p)]
(hpTwo : p ≠ 2)
(delta : ℝ)
(hdelta : delta ≤ 1 / 2)
(x : NormalizedPoint (ZMod p))
(hx : IsNormalizedMarkoff x)
(hnonzero : x.u1 ≠ 0)
(hnonparabolic : x.u1 ^ 2 ≠ 4)
(hbelowEndgame : ↑(rotationOrder x.u1) < ↑p ^ (1 / 2 + delta))
(hcube :
(corvajaZannierCorollaryTwoSafeCoefficient * ((p - 1).divisors.card + (p + 1).divisors.card)) ^ 3 < rotationOrder x.u1)
(hlinear :
corvajaZannierCorollaryTwoSafeCoefficient * ((p - 1).divisors.card + (p + 1).divisors.card) * rotationOrder x.u1 < p)
(hBound : WeightedTraceTorsionIntersectionBound p (quadraticFiniteField p))
:
∃ (n : ℕ), rotationOrder x.u1 < rotationOrder (normalizedRotate1^[n] x).u2
The uniform weighted-trace bound, after Lean verifies every concrete diagonalized Markoff trace curve, produces an actual middle-game order-increasing iterate.