Spatial diffusion calculus below the public AMNR facade.
theorem
AVenhance.Infra.Section4.amnr_energy_coordinate_derivatives_commute
{f : Homogenization.Vec 2 → ℝ}
(hf : ContDiff ℝ (↑⊤) f)
(i j : Fin 2)
(x : Homogenization.Vec 2)
:
spaceGrad (fun (y : Homogenization.Vec 2) => spaceGrad f y i) x j = spaceGrad (fun (y : Homogenization.Vec 2) => spaceGrad f y j) x i
theorem
AVenhance.Infra.Section4.amnr_energy_gradient_laplacian_commute
{f : Homogenization.Vec 2 → ℝ}
(hf : ContDiff ℝ (↑⊤) f)
(x : Homogenization.Vec 2)
(i : Fin 2)
:
The gradient of the Laplacian is the componentwise Laplacian of the gradient. This justifies moving current diffusion derivatives to the preceding increment in the oscillatory material pairing.