OAI/MathematicalPhysics/Boltzmann/Approximation/PositiveIntegralFixedPoint.lean

GitHub source file

17 declarations, 0 contain sorry, 0 declared as axioms

Positive integral contraction along measurable characteristics

This lemma constructs a fixed point of a bounded positive source map. The collision source and its quantitative estimates are supplied separately.

  1. abbrev OAI.BoltzmannNonuniqueness.PositiveIntegral.Domain line 24
  2. def OAI.BoltzmannNonuniqueness.PositiveIntegral.time line 26
  3. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.time_bounds line 28
  4. def OAI.BoltzmannNonuniqueness.PositiveIntegral.value line 32
  5. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.measurable_value line 38
  6. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.value_bounds line 74
  7. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.damped_integrable line 103
  8. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.value_difference line 120
  9. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.exists_fixed_point line 144

    Source documentation

    Positive Picard iteration converges in the complete sup-norm space.

    theorem exists_fixed_point {T L A R S K : ℝ} (hT : 0 ≤ T) (hL : 0 ≤ L)
        (hA : 0 ≤ A) (hR : 0 ≤ R) (hS : 0 ≤ S) (hK : 0 ≤ K)
        (hball : A + T * S ≤ R) (hsmall : T * K < 1)
        {flow : ℝ → P → P} (hflow : Measurable (fun z : ℝ × P => flow z.1 z.2))
        {f₀ : P → ℝ} (hf₀m : Measurable f₀) (hf₀ : ∀ p, 0 ≤ f₀ p ∧ f₀ p ≤ A)
        (source : BoundedMeasurable.PositiveBall (Domain P) R → Domain P → ℝ)
        (hsm : ∀ f, Measurable (source f))
        (hsb : ∀ f z, 0 ≤ source f z ∧ source f z ≤ S)
        (hsl : ∀ f g z, |source f z - source g z| ≤ K * dist f g) :
        ∃ f : BoundedMeasurable.PositiveBall (Domain P) R,
          ∀ z, f.val z = value T L flow f₀ (source f) z := by
    …

    Mentions: OAI.BoltzmannNonuniqueness.BoundedMeasurable.PositiveBall, OAI.BoltzmannNonuniqueness.PositiveIntegral.Domain, OAI.BoltzmannNonuniqueness.PositiveIntegral.value

  10. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.value_mono line 207
  11. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.value_tendsto line 220
  12. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.value_rescale line 255
  13. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.fixed_point_unique line 305
  14. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.value_difference_initial line 345
  15. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.value_finsetSum line 383
  16. theorem OAI.BoltzmannNonuniqueness.PositiveIntegral.hasSum_value line 418
  17. theorem OAI.BoltzmannNonuniqueness.positive_marginal_bound line 462