Recovering an integral path from the scalar weak time equation #
Separated tests against a fixed spatial Fourier mode give a scalar distributional equation. Subtracting the forcing primitive turns it into zero pairing against all compactly supported interior tests, where the distribution separation lemma applies.
noncomputable def
AVenhance.Infra.Parabolic.WeakUniqueness.ScalarPath.terminalPrimitive
(g : ℝ → ℝ)
(t : ℝ)
:
A smooth compactly supported interior function has a smooth terminal primitive.
Equations
Instances For
theorem
AVenhance.Infra.Parabolic.WeakUniqueness.ScalarPath.terminalPrimitive_hasDerivAt
{g : ℝ → ℝ}
(hg : ContDiff ℝ (↑⊤) g)
(t : ℝ)
:
HasDerivAt (terminalPrimitive g) (-g t) t
Clamp real time to the closed unit interval for a weak scalar path.
Equations
Instances For
theorem
AVenhance.Infra.Parabolic.WeakUniqueness.ScalarPath.clampUnitTime_eq
{t : ℝ}
(ht : t ∈ Set.Icc 0 1)
:
theorem
AVenhance.Infra.Parabolic.WeakUniqueness.scalar_weak_tests_imply_integral_path
{u q : ℝ → ℝ}
{u₀ : ℝ}
(hu : ContinuousOn u (Set.Icc 0 1))
(hq : IntervalIntegrable q MeasureTheory.volume 0 1)
(hweak :
∀ (η : ℝ → ℝ),
ContDiff ℝ (↑⊤) η → (∀ (t : ℝ), 1 ≤ t → η t = 0) → ∫ (t : ℝ) in 0..1, -u t * deriv η t + q t * η t = u₀ * η 0)
(t : ℝ)
:
A scalar weak time equation with integrable forcing has the corresponding absolutely continuous integral path.