Super Step Const Inv le
DeGiorgi.superStepConstInv_le
Plain-language statement
Each inverse-power step constant is bounded by a simpler expression. The key simplification: pₙ/(1+pₙ) ≤ pₙ (since pₙ > 0), and gap_n = 2^{-(n+2)}, so 1/gap_n² = 4^{n+2} = 16 · 4^n.
Exact Lean statement
theorem superStepConstInv_le
(hd : 2 < (d : ℝ))
(A : NormalizedEllipticCoeff d (Metric.ball (0 : E) 1))
{p₀ : ℝ} (hp₀ : 0 < p₀) (i : ℕ) :
superStepConstInv (d := d) A p₀ i ≤
(16 * C_MoserAnchor d * (A.1.Λ * p₀ ^ 2 + 1) *
(4 * moserChi d ^ 2) ^ i) ^
(1 / moserExponentSeq d p₀ i)Formal artifact
Lean source
theorem superStepConstInv_le (hd : 2 < (d : ℝ)) (A : NormalizedEllipticCoeff d (Metric.ball (0 : E) 1)) {p₀ : ℝ} (hp₀ : 0 < p₀) (i : ℕ) : superStepConstInv (d := d) A p₀ i ≤ (16 * C_MoserAnchor d * (A.1.Λ * p₀ ^ 2 + 1) * (4 * moserChi d ^ 2) ^ i) ^ (1 / moserExponentSeq d p₀ i) := by unfold superStepConstInv apply Real.rpow_le_rpow · -- Nonnegativity of the base apply mul_nonneg · exact div_nonneg (le_trans (by norm_num : (0 : ℝ) ≤ 1) (one_le_C_MoserAnchor (d := d))) (sq_nonneg _) · nlinarith [A.1.Λ_nonneg, sq_nonneg (moserExponentSeq d p₀ i / (1 + moserExponentSeq d p₀ i))] · -- Main bound have hp_i := moserExponentSeq_pos (d := d) hd hp₀ i have hgap_eq : C_MoserAnchor d / (moserRadius i - moserRadius (i + 1)) ^ 2 = C_MoserAnchor d * (4 : ℝ) ^ (i + 2) := by rw [moserRadius_gap] have hsq : (((1 / 2 : ℝ) ^ (i + 2)) ^ 2) = (1 / 4 : ℝ) ^ (i + 2) := by rw [← pow_mul, show (i + 2) * 2 = 2 * (i + 2) by ring, pow_mul]; norm_num rw [hsq, div_eq_mul_inv, show (((1 / 4 : ℝ) ^ (i + 2))⁻¹) = (4 : ℝ) ^ (i + 2) by rw [show (1 / 4 : ℝ) = (4 : ℝ)⁻¹ by norm_num, inv_pow]; norm_num] have hpow4 : (4 : ℝ) ^ (i + 2) = 16 * 4 ^ i := by rw [pow_add]; ring -- pₙ/(1+pₙ) ≤ pₙ, so Λ(pₙ/(1+pₙ))² ≤ Λpₙ² have hratio_le : (moserExponentSeq d p₀ i / (1 + moserExponentSeq d p₀ i)) ^ 2 ≤ (moserExponentSeq d p₀ i) ^ 2 := by have hdiv_le : moserExponentSeq d p₀ i / (1 + moserExponentSeq d p₀ i) ≤ moserExponentSeq d p₀ i := div_le_self hp_i.le (by linarith) have hdiv_nonneg : 0 ≤ moserExponentSeq d p₀ i / (1 + moserExponentSeq d p₀ i) := div_nonneg hp_i.le (by linarith) nlinarith [sq_nonneg (moserExponentSeq d p₀ i - moserExponentSeq d p₀ i / (1 + moserExponentSeq d p₀ i))] -- pₙ² = p₀² · χ^{2i} have hseq_sq : (moserExponentSeq d p₀ i) ^ 2 = p₀ ^ 2 * (moserChi d) ^ (2 * i) := by rw [moserExponentSeq]; ring -- Combine: Λ(pₙ/(1+pₙ))² + 1 ≤ (Λp₀² + 1) · χ^{2i} have hcoeff_le : A.1.Λ * (moserExponentSeq d p₀ i / (1 + moserExponentSeq d p₀ i)) ^ 2 + 1 ≤ (A.1.Λ * p₀ ^ 2 + 1) * (moserChi d ^ 2) ^ i := by have hchi_sq_ge_one : 1 ≤ (moserChi d ^ 2) ^ i := one_le_pow₀ (by nlinarith [one_lt_moserChi (d := d) hd]) have hΛratio : A.1.Λ * (moserExponentSeq d p₀ i / (1 + moserExponentSeq d p₀ i)) ^ 2 ≤ A.1.Λ * p₀ ^ 2 * (moserChi d ^ 2) ^ i := by calc A.1.Λ * (moserExponentSeq d p₀ i / (1 + moserExponentSeq d p₀ i)) ^ 2 ≤ A.1.Λ * (moserExponentSeq d p₀ i) ^ 2 := mul_le_mul_of_nonneg_left hratio_le A.1.Λ_nonneg _ = A.1.Λ * (p₀ ^ 2 * (moserChi d) ^ (2 * i)) := by rw [hseq_sq] _ = A.1.Λ * p₀ ^ 2 * (moserChi d ^ 2) ^ i := by rw [pow_mul]; ring nlinarith rw [hgap_eq, hpow4] calc C_MoserAnchor d * (16 * 4 ^ i) * (A.1.Λ * (moserExponentSeq d p₀ i / (1 + moserExponentSeq d p₀ i)) ^ 2 + 1) ≤ C_MoserAnchor d * (16 * 4 ^ i) * ((A.1.Λ * p₀ ^ 2 + 1) * (moserChi d ^ 2) ^ i) := by gcongr exact mul_nonneg (le_trans (by norm_num : (0 : ℝ) ≤ 1) (one_le_C_MoserAnchor (d := d))) (by positivity) _ = 16 * C_MoserAnchor d * (A.1.Λ * p₀ ^ 2 + 1) * (4 * moserChi d ^ 2) ^ i := by rw [show (4 * moserChi d ^ 2) ^ i = 4 ^ i * (moserChi d ^ 2) ^ i by rw [mul_pow]] ring · exact div_nonneg (by norm_num) (moserExponentSeq_pos (d := d) hd hp₀ i).le- Project
- DeGiorgi
- License
- Apache-2.0
- Commit
- 4c1b3077d378
- Source
- DeGiorgi/Supersolutions/InverseIteration.lean:137-201
Reuse this declaration
Bring the exact result into your workflow
The import identifies the source module. Your project still needs the pinned package dependency shown on this page.
What this badge means
This completion status comes from the project or community source. It has not yet been represented here as an independent rebuild and axiom audit.
Continue in this project
Related declarations
Ae eq of tendsto e Lp Norm sub
BareFunction.ae_eq_of_tendsto_eLpNorm_sub
Plain-language statement
Lp limit uniqueness: if f_n → g₁ and f_n → g₂ in eLpNorm, then g₁ =ᵐ g₂.
Source project: DeGiorgi
Person-level attribution pending.
E Lp Norm pi le sum component
BareFunction.eLpNorm_pi_le_sum_component
Plain-language statement
Vector eLpNorm ≤ sum of component eLpNorms for Pi-valued functions. Uses eLpNorm_mono_real for the pointwise bound together with eLpNorm_sum_le for ℝ-valued functions, avoiding Pi instance synthesis.
Source project: DeGiorgi
Person-level attribution pending.
Mem Lp of tendsto e Lp Norm
BareFunction.memLp_of_tendsto_eLpNorm
Plain-language statement
If f n → g in eLpNorm and each f n ∈ Lp, then g ∈ Lp, provided g is AEStronglyMeasurable. Avoids the Lp type entirely. The key observation: eLpNorm (f n - g) → 0 means eLpNorm (f N - g) < 1 for some N. Then eLpNorm g ≤ eLpNorm (f N - g) + eLpNorm (f N) < ∞.
Source project: DeGiorgi
Person-level attribution pending.