One-parameter family of fast planes transverse to translations
OpenFiniteEnergyPlane.exists_fastPlane_slice_familyLet be a strictly star-shaped level with a compatible complex structure on , and let be a periodic Reeb orbit on whose Conley–Zehnder index is at least . Let be an embedded fast finite-energy plane asymptotic to at . Then for every there are and a map such that:
- ;
- every , , is a fast finite-energy plane asymptotic to at ;
- the map is injective on ;
- this map has injective derivative everywhere: if with and , then , and .
Thus the planes form a one-parameter family through that is transverse to the -translations in the symplectization, and the small translates of its members are pairwise disjoint. This is the geometric content of Hryniewicz, Fast finite-energy planes in symplectizations and applications, Trans. AMS 364 (2012), Lemmas 6.10 and 6.20, written in a form where the -translation parameter is explicit.
Formalization Note: is the model of the symplectization , in which the translation by is . Item 4 is the injectivity of the derivative of the map in item 3 at , after dividing by and writing . Since the map is only asserted to be on the open set , no uniformity as is part of the statement. Non-vacuity: for the round sphere with , satisfies the conclusion for .
import Definitions.Def_FiniteEnergyPlane_Fredholm
namespace FiniteEnergyPlane
open MeasureTheory Metric Filter Topology
open scoped ContDiff ENNReal Real
/-- A one-parameter family of fast planes through an embedded fast plane, transverse to the
`ℝ`-translations. Let `u` be an embedded fast finite-energy plane asymptotic to `P` at `∞`, where
the Conley–Zehnder index of `P` is at least `3`. Then for every `l ≥ 1` there are `r > 0` and a
`C^l` map `g : ℂ × (-r, r) → V 1` with `g(·, 0) = u` such that every `g(·, t)` is a fast
finite-energy plane asymptotic to `P` at `∞`, and such that
`(z, c, t) ↦ c · g(z, t) = e^{2c} • g(z, t)` is injective on `ℂ × (-r, r) × (-r, r)` with injective
derivative. The latter is stated at `c = 0`: `D g(z, t)(Δ, δt) + λ • g(z, t) = 0` forces
`Δ = 0`, `δt = 0` and `λ = 0`. -/
theorem exists_fastPlane_slice_family (H : V 1 → ℝ) (hH : IsStrictlyStarShapedLevel H)
(J : V 1 → V 1 →L[ℝ] V 1) (hJ : IsCompatibleXiStructure H J)
(P : ReebOrbit H) (hcz : P.IsCZAtLeast 3) (u : ℂ → V 1)
(hu : IsFastPlane H J u) (huP : IsNondegenerateEnd H u cylInf P 1)
(hue : IsEmbeddedPlane u) (l : ℕ) (hl : 1 ≤ l) :
∃ r > 0, ∃ g : ℂ × ℝ → V 1, ContDiffOn ℝ l g (Set.univ ×ˢ Set.Ioo (-r) r) ∧
(∀ z, g (z, 0) = u z) ∧
(∀ t ∈ Set.Ioo (-r) r, IsFastPlane H J (fun z => g (z, t)) ∧
IsNondegenerateEnd H (fun z => g (z, t)) cylInf P 1) ∧
Set.InjOn (fun q : ℂ × ℝ × ℝ => Real.exp (2 * q.2.1) • g (q.1, q.2.2))
(Set.univ ×ˢ (Set.Ioo (-r) r ×ˢ Set.Ioo (-r) r)) ∧
∀ z, ∀ t ∈ Set.Ioo (-r) r, ∀ (Δ : ℂ) (δt lam : ℝ),
fderiv ℝ g (z, t) (Δ, δt) + lam • g (z, t) = 0 → Δ = 0 ∧ δt = 0 ∧ lam = 0 := by
sorry
end FiniteEnergyPlane