OAI/MathematicalPhysics/DefocusingNLS/Linear/SchrodingerGenerator.lean

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12 declarations, 0 contain sorry, 0 declared as axioms

Two-derivative loss for the free Schrödinger evolution

In the common weighted-ℓ² model, the inclusion from H^k to H^(k-2) multiplies by (1+|n|²)⁻¹. The time derivative is the bounded multiplier -i |n|²/(1+|n|²). Finite Fourier sums give the derivative of the full flow by uniform convergence of their derivatives.

  1. def OAI.DefocusingNLS.fourierContraction line 23

    Source documentation

    A bounded Fourier multiplier of norm at most one.

    Also declared: ComparatorChallenges/DefocusingNLS.lean:163 (same declaration text).

    noncomputable def fourierContraction (m : frequencyLattice → ℂ)
        (hm : ∀ n, ‖m n‖ ≤ 1) : FourierL2 →L[ℂ] FourierL2 :=
    …

    Mentions: OAI.DefocusingNLS.frequencyLattice, OAI.DefocusingNLS.FourierL2

  2. theorem OAI.DefocusingNLS.fourierContraction_apply line 49
  3. def OAI.DefocusingNLS.lowerSobolevInclusion line 54

    Source documentation

    The continuous inclusion from H^k into H^(k-2), in weighted coordinates.

    Also declared: ComparatorChallenges/DefocusingNLS.lean:189 (same declaration text).

    noncomputable def lowerSobolevInclusion : FourierL2 →L[ℂ] FourierL2 :=
    …

    Mentions: OAI.DefocusingNLS.FourierL2

  4. def OAI.DefocusingNLS.lowerSobolevGenerator line 61

    Source documentation

    The free Schrödinger generator, with the loss of two Sobolev derivatives.

    Distinct definitions of this name: ComparatorChallenges/DefocusingNLS.lean:195 (same statement text; different proof or body). Qualify references as OAI.DefocusingNLS.lowerSobolevGenerator@path.

    noncomputable def lowerSobolevGenerator : FourierL2 →L[ℂ] FourierL2 :=
    …

    Mentions: OAI.DefocusingNLS.FourierL2

  5. theorem OAI.DefocusingNLS.lowerSobolevInclusion_apply line 68
  6. theorem OAI.DefocusingNLS.lowerSobolevGenerator_apply line 71
  7. theorem OAI.DefocusingNLS.sobolevFourierCoefficient_lower_inclusion line 76

    Source documentation

    The inclusion changes the Sobolev index without changing physical Fourier coefficients.

    theorem sobolevFourierCoefficient_lower_inclusion (k : ℝ) (f : FourierL2)
        (n : frequencyLattice) :
        sobolevFourierCoefficient (k - 2) (lowerSobolevInclusion f) n =
          sobolevFourierCoefficient k f n := by
    …

    Mentions: OAI.DefocusingNLS.FourierL2, OAI.DefocusingNLS.frequencyLattice, OAI.DefocusingNLS.sobolevFourierCoefficient, OAI.DefocusingNLS.lowerSobolevInclusion

  8. theorem OAI.DefocusingNLS.schrodingerFlow_single line 91

    Source documentation

    Applying the free group to one coordinate keeps that coordinate.

    theorem schrodingerFlow_single (t : ℝ) (n : frequencyLattice) (c : ℂ) :
        schrodingerFlow t (lp.single 2 n c) =
          lp.single 2 n (schrodingerMultiplier t n * c) := by
    …

    Mentions: OAI.DefocusingNLS.frequencyLattice, OAI.DefocusingNLS.schrodingerMultiplier

  9. theorem OAI.DefocusingNLS.tendstoUniformly_schrodingerFlow_partials line 101

    Source documentation

    Uniform-in-time convergence of the finite Fourier approximations.

    theorem tendstoUniformly_schrodingerFlow_partials (f : FourierL2) :
        TendstoUniformly
          (fun S : Finset frequencyLattice => fun t : ℝ =>
            ∑ n ∈ S, lp.single 2 n (schrodingerMultiplier t n * f n))
          (fun t => schrodingerFlow t f) atTop := by
    …

    Mentions: OAI.DefocusingNLS.FourierL2, OAI.DefocusingNLS.frequencyLattice, OAI.DefocusingNLS.schrodingerMultiplier

  10. theorem OAI.DefocusingNLS.hasDerivAt_schrodingerMultiplier_mul line 118

    Source documentation

    The scalar phase has the exact Schrödinger derivative.

    theorem hasDerivAt_schrodingerMultiplier_mul (n : frequencyLattice) (c : ℂ) (t : ℝ) :
        HasDerivAt (fun s : ℝ => schrodingerMultiplier s n * c)
          (schrodingerMultiplier t n * (-Complex.I * ((‖n‖ ^ 2 : ℝ) : ℂ) * c)) t := by
    …

    Mentions: OAI.DefocusingNLS.frequencyLattice, OAI.DefocusingNLS.schrodingerMultiplier

  11. theorem OAI.DefocusingNLS.hasDerivAt_schrodingerFlow_of_generator line 127

    Source documentation

    Coordinatewise Schrödinger differentiation yields differentiation in ℓ² when the derivative coordinates also form an ℓ² vector.

    theorem hasDerivAt_schrodingerFlow_of_generator (f v : FourierL2)
        (hv : ∀ n, v n = -Complex.I * ((‖n‖ ^ 2 : ℝ) : ℂ) * f n) (t : ℝ) :
        HasDerivAt (fun s : ℝ => schrodingerFlow s f) (schrodingerFlow t v) t := by
    …

    Mentions: OAI.DefocusingNLS.FourierL2

  12. theorem OAI.DefocusingNLS.hasDerivAt_lowerSobolev_schrodingerFlow line 142

    Source documentation

    The free evolution is differentiable as an H^(k-2)-valued function.

    theorem hasDerivAt_lowerSobolev_schrodingerFlow (f : FourierL2) (t : ℝ) :
        HasDerivAt (fun s => schrodingerFlow s (lowerSobolevInclusion f))
          (schrodingerFlow t (lowerSobolevGenerator f)) t := by
    …

    Mentions: OAI.DefocusingNLS.FourierL2, OAI.DefocusingNLS.lowerSobolevInclusion