OAI/Geometry/RCD/Metric/ScalarMetricBootstrap.lean
11 declarations, 0 contain sorry, 0 declared as axioms
Finite-scale scalar metric bootstrap
Fixing a testing point and a direction turns the manuscript's matrix estimates
into real sequences. Here z is the local mass in that direction, d is the
weighted defect, and b is the normalized diagonal second derivative. The
signed first-order errors and nonnegative squared increment are kept explicit.
Finite summation and Cauchy--Schwarz estimates close the bootstrap from these scalar premises, without further geometric assumptions.
- theorem
OAI.RegularPointCoordinates.weighted_defect_sum_leline 26Source documentation
Monotonicity of the scale metrics converts the unweighted defect budget to the weighted one used in the metric estimate.
theorem weighted_defect_sum_le {e H : ℕ → ℝ} {epsilon Q : ℝ} (he : ∀ i, 0 ≤ e i) (hQ : 0 ≤ Q) (k : ℕ) (hH : ∀ i < k, H i ≤ Q) (hebudget : (∑ i ∈ Finset.range k, e i) ≤ epsilon) : (∑ i ∈ Finset.range k, e i * H i) ≤ epsilon * Q := by … - theorem
OAI.RegularPointCoordinates.leading_metric_comparisonline 41Source documentation
The cumulative upper/lower local-mass comparisons imply the leading metric comparison before the signed error is introduced.
theorem leading_metric_comparison {s z : ℕ → ℝ} {base Q T : ℝ} (hbase : 0 ≤ base) (hT : 0 < T) (hs : ∀ i, 0 ≤ s i) (k : ℕ) (hsz : ∀ i < k, s i ≤ z i) (hlower : Q ≤ T * (base + ∑ i ∈ Finset.range k, s i)) (hupper : base + (∑ i ∈ Finset.range k, z i) ≤ T * Q) : T⁻¹ * Q ≤ base + 2 * (∑ i ∈ Finset.range k, s i) ∧ base + 2 * (∑ i ∈ Finset.range k, s i) ≤ 2 * T * Q := by … - theorem
OAI.RegularPointCoordinates.sum_sqrt_mul_sqrt_leline 57Source documentation
Cauchy--Schwarz for square roots of nonnegative scalar budgets.
theorem sum_sqrt_mul_sqrt_le {z d : ℕ → ℝ} (hz : ∀ i, 0 ≤ z i) (hd : ∀ i, 0 ≤ d i) (k : ℕ) : (∑ i ∈ Finset.range k, Real.sqrt (z i) * Real.sqrt (d i)) ≤ Real.sqrt (∑ i ∈ Finset.range k, z i) * Real.sqrt (∑ i ∈ Finset.range k, d i) := by … - theorem
OAI.RegularPointCoordinates.diagonal_recurrence_square_budgetline 73Source documentation
The diagonal recurrence converts the forcing budgets to a square sum.
theorem diagonal_recurrence_square_budget {z d b : ℕ → ℝ} {C : ℝ} (hz : ∀ i, 0 ≤ z i) (hd : ∀ i, 0 ≤ d i) (hb : ∀ i, 0 ≤ b i) (hbzero : b 0 = 0) (k : ℕ) (hrec : ∀ i < k, b (i + 1) ≤ b i / 2 + C * (Real.sqrt (z i) + Real.sqrt (d i))) : (∑ i ∈ Finset.range k, b i ^ 2) ≤ 8 * C ^ 2 * ((∑ i ∈ Finset.range k, z i) + ∑ i ∈ Finset.range k, d i) := by … - theorem
OAI.RegularPointCoordinates.scalar_metric_cumulative_errorline 98Source documentation
Summing the exact metric increment and estimating its three errors. Only the displayed finite-scale premises are used.
theorem scalar_metric_cumulative_error {m s z d b linear inverse square : ℕ → ℝ} {C epsilon : ℝ} (hC : 0 ≤ C) (hz : ∀ i, 0 ≤ z i) (hd : ∀ i, 0 ≤ d i) (hb : ∀ i, 0 ≤ b i) (hbzero : b 0 = 0) (k : ℕ) (hrec : ∀ i < k, b (i + 1) ≤ b i / 2 + C * (Real.sqrt (z i) + Real.sqrt (d i))) (hlinear : ∀ i < k, |linear i| ≤ C * Real.sqrt (z i) * Real.sqrt (d i)) (hinverse : ∀ i < k, |inverse i| ≤ C * b i * Real.sqrt (d i)) (hsquare : ∀ i < k, |square i| ≤ C * epsilon * (z i + d i)) (hstep : ∀ i < k, m (i + 1) - m i = 2 * s i + 2 * linear i + 2 * inverse i + square i) : |m k - m 0 - 2 * ∑ i ∈ Finset.range k, s i| ≤ … - def
OAI.RegularPointCoordinates.scalarMetricErrorCoefficientline 164Source documentation
An explicit coefficient for the cumulative metric error after using the local-mass and weighted-defect budgets.
noncomputable def scalarMetricErrorCoefficient (C T epsilon : ℝ) : ℝ := …
- theorem
OAI.RegularPointCoordinates.scalarMetricErrorCoefficient_tendsto_zeroline 170Source documentation
The coefficient can be made arbitrarily small after fixing
CandT.theorem scalarMetricErrorCoefficient_tendsto_zero (C T : ℝ) : Tendsto (scalarMetricErrorCoefficient C T) (𝓝 0) (𝓝 0) := by …Mentions: OAI.RegularPointCoordinates.scalarMetricErrorCoefficient
- theorem
OAI.RegularPointCoordinates.scalar_metric_error_of_budgetsline 179Source documentation
The full finite metric error is proportional to the final directional metric
Q, even if that metric grows with the scale.theorem scalar_metric_error_of_budgets {m s z d b linear inverse square : ℕ → ℝ} {C T epsilon Q : ℝ} (hC : 0 ≤ C) (hT : 0 ≤ T) (hepsilon : 0 ≤ epsilon) (hQ : 0 ≤ Q) (hz : ∀ i, 0 ≤ z i) (hd : ∀ i, 0 ≤ d i) (hb : ∀ i, 0 ≤ b i) (hbzero : b 0 = 0) (k : ℕ) (hrec : ∀ i < k, b (i + 1) ≤ b i / 2 + C * (Real.sqrt (z i) + Real.sqrt (d i))) (hlinear : ∀ i < k, |linear i| ≤ C * Real.sqrt (z i) * Real.sqrt (d i)) (hinverse : ∀ i < k, |inverse i| ≤ C * b i * Real.sqrt (d i)) (hsquare : ∀ i < k, |square i| ≤ C * epsilon * (z i + d i)) (hstep : ∀ i < k, m (i + 1) - m i = 2 * s i + 2 * linear i + 2 * inverse i + square i) … - theorem
OAI.RegularPointCoordinates.scalar_metric_comparison_closesline 229Source documentation
Leading metric comparison and a small cumulative error close the bootstrap.
theorem scalar_metric_comparison_closes {M leading Q T eta : ℝ} (hQ : 0 ≤ Q) (hT : 0 < T) (hlower : T⁻¹ * Q ≤ leading) (hupper : leading ≤ 2 * T * Q) (herror : |M - leading| ≤ eta * Q) (hsmall : eta ≤ (2 * T)⁻¹) : (2 * T)⁻¹ * Q ≤ M ∧ M ≤ (2 * T + (2 * T)⁻¹) * Q := by … - theorem
OAI.RegularPointCoordinates.scalar_metric_fourfold_comparisonline 245Source documentation
Choosing the bootstrap constant
4Tgives its lower and upper bounds.theorem scalar_metric_fourfold_comparison {M leading Q T eta : ℝ} (hQ : 0 ≤ Q) (hT : 1 ≤ T) (hlower : T⁻¹ * Q ≤ leading) (hupper : leading ≤ 2 * T * Q) (herror : |M - leading| ≤ eta * Q) (hsmall : eta ≤ (2 * T)⁻¹) : (4 * T)⁻¹ * Q ≤ M ∧ M ≤ (4 * T) * Q := by … - theorem
OAI.RegularPointCoordinates.scalar_metric_bootstrapline 263Source documentation
The scalar recurrence, three error estimates, two budgets, and leading comparison imply the metric bootstrap bounds.
theorem scalar_metric_bootstrap {m s z d b linear inverse square : ℕ → ℝ} {C T epsilon Q : ℝ} (hC : 0 ≤ C) (hT : 1 ≤ T) (hepsilon : 0 ≤ epsilon) (hQ : 0 ≤ Q) (hz : ∀ i, 0 ≤ z i) (hd : ∀ i, 0 ≤ d i) (hb : ∀ i, 0 ≤ b i) (hbzero : b 0 = 0) (k : ℕ) (hrec : ∀ i < k, b (i + 1) ≤ b i / 2 + C * (Real.sqrt (z i) + Real.sqrt (d i))) (hlinear : ∀ i < k, |linear i| ≤ C * Real.sqrt (z i) * Real.sqrt (d i)) (hinverse : ∀ i < k, |inverse i| ≤ C * b i * Real.sqrt (d i)) (hsquare : ∀ i < k, |square i| ≤ C * epsilon * (z i + d i)) (hstep : ∀ i < k, m (i + 1) - m i = 2 * s i + 2 * linear i + 2 * inverse i + square i) …