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Project-declaredLean 4.32.0 · mathlib@81a5d257c8e4

Unbalancing

unbalancing'

Project documentation

An unbalancing lemma in physical space. Suppose ν\nu is a probability weight, ff is real-valued, and ff and ν\nu admit self-difference-convolution factorizations f=ggf=g\mathbin{\circleddash}g and ν=hh\nu=h\mathbin{\circleddash}h. If 0<ε10<\varepsilon\le1, p0p\ne0, and fLp(ν)ε\|f\|_{L^p(\nu)}\ge\varepsilon, then some integer pp' satisfies p210ε2pp'\le 2^{10}\varepsilon^{-2}p and 1+fLp(ν)1+ε/2\|1+f\|_{L^{p'}(\nu)}\ge1+\varepsilon/2.

Exact Lean statement

lemma unbalancing' (p : ℕ) (hp : p ≠ 0) (ε : ℝ) (hε₀ : 0 < ε) (hε₁ : ε ≤ 1) (ν : G → ℝ≥0)
    (f : G → ℝ) (g h : G → ℂ) (hf : g ○ᵈ g = (↑) ∘ f) (hν : h ○ᵈ h = (↑) ∘ ν)
    (hν₁ : ∑ x, ν x = 1) (hε : ε ≤ ‖f‖_[p, ν]) :
    ∃ p' : ℕ, p' ≤ 2 ^ 10 * ε⁻¹ ^ 2 * p ∧ 1 + ε / 2 ≤ ‖f + 1‖_[p', ν]

Formal artifact

Lean source

Canonical source
Full Lean sourceLean 4
lemma unbalancing' (p : ) (hp : p  0) (ε : ) (hε₀ : 0 < ε) (hε₁ : ε  1) (ν : G  0)    (f : G  ) (g h : G  ℂ) (hf : g ○ᵈ g = (↑) ∘ f) (hν : h ○ᵈ h = (↑) ∘ ν)    (hν₁ : ∑ x, ν x = 1) (hε : ε  ‖f‖_[p, ν]) :     p' : , p'  2 ^ 10 * ε⁻¹ ^ 2 * p  1 + ε / 2  ‖f + 1‖_[p', ν] := by  have := log_ε_pos hε₀ hε₁  have : 5  2 * p + 3 := by omega  rw [ Nat.one_le_iff_ne_zero] at hp  refine 120 / ε * log (3 / ε) * p⌉₊, ?_, ?_  · calc      (⌈120 / ε * log (3 / ε) * p⌉₊ : )        =120 * ε⁻¹ * log (3 * ε⁻¹) * p⌉₊ := by simp [div_eq_mul_inv]      _  2 * (120 * ε⁻¹ * log (3 * ε⁻¹) * p) := Nat.ceil_le_two_mul <|        calc          (2⁻¹ : )  120 * 1 * 1 * 1 := by norm_num          _  120 * ε⁻¹ * log (3 * ε⁻¹) * p := by            gcongr            · exact (one_le_inv₀ hε₀).2 hε₁            · rw [ log_exp 1]              gcongr              calc                exp 1  2.7182818286 := exp_one_lt_d9.le                _  3 * 1 := by norm_num                _  3 * ε⁻¹ := by gcongr; exact (one_le_inv₀ hε₀).2 hε₁            · exact mod_cast hp      _  2 * (120 * ε⁻¹ * (3 * ε⁻¹) * p) := by gcongr; exact Real.log_le_self (by positivity)      _  2 * (2 ^ 7 * ε⁻¹ * (2 ^ 2 * ε⁻¹) * p) := by gcongr <;> norm_num      _ = 2 ^ 10 * ε⁻¹ ^ 2 * p := by ring  have hνprob : ∑ x, (ν x : 0∞) = 1 := mod_cast hν₁  calc    1 + ε / 2  ↑‖f + 1‖_[.ofReal (24 / ε * log (3 / ε) * ↑(2 * p + 3)), ν] :=      unbalancing'' (2 * p + 3) this ((even_two_mul _).add_odd <| by decide) hε₀ hε₁ hf hν hν₁ <|        hε.trans <| wLpNorm_mono_right hνprob          (Nat.cast_le.2 <| le_add_of_le_left <| le_mul_of_one_le_left' one_le_two) _    _  _ := wLpNorm_mono_right hνprob ?_ _  norm_cast  calc    _ = 24 / ε * log (3 / ε) * ↑(2 * p + 3 * 1) := by simp    _  24 / ε * log (3 / ε) * ↑(2 * p + 3 * p) := by gcongr    _ = 120 / ε * log (3 / ε) * p := by push_cast; ring    _ 120 / ε * log (3 / ε) * p⌉₊ := Nat.le_ceil _
Project
Arithmetic Progressions Almost Periodicity
License
Apache-2.0
Commit
afafc42a5326
Source
APAP/Physics/Unbalancing.lean:205-244

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