derivative control for the finite low-frequency trace mode #
The finite Fourier cutoff has no derivative loss beyond its physical frequency radius. Parseval compares every nonempty ordered derivative with the full gradient energy of the same cutoff.
def
AVenhance.Infra.Section5.RelativeError.TraceInstanceSpectrum.complexWordDerivative :
List (Fin 2) → (Homogenization.Vec 2 → ℂ) → Homogenization.Vec 2 → ℂ
Ordered complex coordinate derivatives used in the trace spectrum estimate.
Equations
- One or more equations did not get rendered due to their size.
- AVenhance.Infra.Section5.RelativeError.TraceInstanceSpectrum.complexWordDerivative [] x✝ = x✝
Instances For
theorem
AVenhance.Infra.Section5.RelativeError.TraceInstanceSpectrum.complexWordDerivative_contDiff
(w : List (Fin 2))
{f : Homogenization.Vec 2 → ℂ}
(hf : ContDiff ℝ (↑⊤) f)
:
ContDiff ℝ (↑⊤) (complexWordDerivative w f)
theorem
AVenhance.Infra.Section5.RelativeError.TraceInstanceSpectrum.complexWordDerivative_periodic
(w : List (Fin 2))
{f : Homogenization.Vec 2 → ℂ}
(hf : Torus.IsZdPeriodic f)
:
theorem
AVenhance.Infra.Section5.RelativeError.TraceInstanceSpectrum.orderedRealDerivative_contDiff
(w : List (Fin 2))
{f : Homogenization.Vec 2 → ℝ}
(hf : ContDiff ℝ (↑⊤) f)
:
ContDiff ℝ (↑⊤) (orderedRealDerivative w f)
theorem
AVenhance.Infra.Section5.RelativeError.TraceInstanceSpectrum.orderedRealDerivative_periodic
(w : List (Fin 2))
{f : Homogenization.Vec 2 → ℝ}
(hf : IsZ2Periodic f)
:
theorem
AVenhance.Infra.Section5.RelativeError.TraceInstanceSpectrum.complexWordDerivative_realCast
(w : List (Fin 2))
{f : Homogenization.Vec 2 → ℝ}
(hf : ContDiff ℝ (↑⊤) f)
:
Product Fourier multiplier associated with a spatial derivative word.
Equations
- One or more equations did not get rendered due to their size.
- AVenhance.Infra.Section5.RelativeError.TraceInstanceSpectrum.wordFourierMultiplier [] x✝ = 1
Instances For
theorem
AVenhance.Infra.Section5.RelativeError.TraceInstanceSpectrum.complexWordDerivative_fourierCoeff
(w : List (Fin 2))
{f : Homogenization.Vec 2 → ℂ}
(hf : ContDiff ℝ (↑⊤) f)
(hper : Torus.IsZdPeriodic f)
(k : Fin 2 → ℤ)
:
theorem
AVenhance.Infra.Section5.RelativeError.TraceInstanceSpectrum.lowProjection_complexFourierCoeff
{g : Homogenization.Vec 2 → ℝ}
(M : ℕ)
(k : Fin 2 → ℤ)
:
theorem
AVenhance.Infra.Section5.RelativeError.lowProjection_orderedDerivative_l2_le
{g : Homogenization.Vec 2 → ℝ}
(w : List (Fin 2))
(hw : 1 ≤ w.length)
(M : ℕ)
:
√(∫ (x : Homogenization.Vec 2) in Torus.unitCell 2, orderedRealDerivative w (Ergodic.lowProjection g M) x ^ 2) ≤ (2 * Real.pi * √2 * ↑M) ^ (w.length - 1) * √(gradNormSq (spaceGrad (Ergodic.lowProjection g M)))
Every positive-order real coordinate derivative of the cutoff is bounded
in cell L² by its full gradient energy and the physical cutoff radius.