OAI/Analysis/Mahler/RegularPartition.lean

GitHub source file

5 declarations, 0 contain sorry, 0 declared as axioms

  1. theorem OAI.MahlerStokes.exists_compact_smooth_partition line 14

    Source documentation

    An actual smooth partition with compact supports in a given finite bounded open cover, equal to one on a neighborhood of the compact set.

    theorem exists_compact_smooth_partition {d : ℕ} {ι : Type} [Fintype ι]
        {K : Set (Fin d → ℝ)} (hK : IsCompact K) (V : ι → Set (Fin d → ℝ))
        (hVo : ∀ i, IsOpen (V i)) (hVb : ∀ i, Bornology.IsBounded (V i))
        (hcover : K ⊆ ⋃ i, V i) :
        ∃ (W : Set (Fin d → ℝ))
          (ρ : SmoothPartitionOfUnity ι 𝓘(ℝ, Fin d → ℝ) (Fin d → ℝ) (closure W)),
          IsOpen W ∧ K ⊆ W ∧ IsCompact (closure W) ∧
          ρ.IsSubordinate V ∧ (∀ i, HasCompactSupport (ρ i)) ∧
          (∀ x ∈ W, ∑ i, ρ i x = 1) := by
    …
  2. theorem OAI.MahlerStokes.RegularBoundaryAtlas.exists_partition line 35

    Source documentation

    The boundary atlas has an actual finite smooth subordinate partition, with compact supports and sum one on a boundary neighborhood.

    theorem RegularBoundaryAtlas.exists_partition {d : ℕ} {U K : Set (Fin d → ℝ)}
        {g : (Fin d → ℝ) → ℝ} (a : RegularBoundaryAtlas d U g K) (hK : IsCompact K) :
        ∃ (W : Set (Fin d → ℝ))
          (ρ : SmoothPartitionOfUnity a.Index 𝓘(ℝ, Fin d → ℝ) (Fin d → ℝ) (closure W)),
          IsOpen W ∧ K ⊆ W ∧ IsCompact (closure W) ∧
          (∀ i, tsupport (ρ i) ⊆ (a.patch i).domain) ∧
          (∀ i, HasCompactSupport (ρ i)) ∧ (∀ x ∈ W, ∑ i, ρ i x = 1) :=
    …

    Mentions: OAI.MahlerStokes.RegularBoundaryAtlas

  3. def OAI.MahlerStokes.sublevelPatchDomain line 47

    Source documentation

    Adjoin the actual sublevel as the interior patch. This finite cover covers the whole closure, so derivative cancellation can be used throughout D_R.

    def sublevelPatchDomain {d : ℕ} {U : Set (Fin d → ℝ)} {g : (Fin d → ℝ) → ℝ}
        {R : ℝ} (a : RegularBoundaryAtlas d U g (frontier (regularSublevel U g R))) :
        Option a.Index → Set (Fin d → ℝ)
      | none => regularSublevel U g R
      | some i => (a.patch i).domain

    Mentions: OAI.MahlerStokes.RegularBoundaryAtlas, OAI.MahlerStokes.regularSublevel

  4. theorem OAI.MahlerStokes.sublevelPatchDomain_covers line 53
  5. theorem OAI.MahlerStokes.exists_sublevel_partition line 66