Transport integration by parts for the material oscillatory terms in l.V.
theorem
AVenhance.Infra.Section4.IteratesMaterial.material_gradient_continuous
{u : Homogenization.Vec 2 → ℝ}
(hu : ContDiff ℝ (↑⊤) u)
:
Continuous (spaceGrad u)
theorem
AVenhance.Infra.Section4.IteratesMaterial.material_stream_continuous
{φ : Homogenization.Vec 2 → ℝ}
(hφ : ContDiff ℝ (↑⊤) φ)
:
Continuous (streamVel (fun (x : ℝ) => φ) 0)
theorem
AVenhance.Infra.Section4.IteratesMaterial.material_dot_continuous
{a b : Homogenization.Vec 2 → Homogenization.Vec 2}
(ha : Continuous a)
(hb : Continuous b)
:
Continuous fun (x : Homogenization.Vec 2) => Homogenization.vecDot (a x) (b x)
theorem
AVenhance.Infra.Section4.iterate_stream_transport_pairing_skew
{φ u v : Homogenization.Vec 2 → ℝ}
(hφ : ContDiff ℝ (↑⊤) φ)
(hφper : IsZ2Periodic φ)
(hu : ContDiff ℝ (↑⊤) u)
(hv : ContDiff ℝ (↑⊤) v)
(hup : IsZ2Periodic u)
(hvp : IsZ2Periodic v)
:
Polarization of the stream energy cancellation gives the transport integration by parts needed for two different increment derivatives.
theorem
AVenhance.Infra.Section4.iterate_material_product_pairing
{φ u v : ℝ → Homogenization.Vec 2 → ℝ}
{t : ℝ}
(hφ : ContDiff ℝ (↑⊤) (φ t))
(hφp : IsZ2Periodic (φ t))
(hu : ContDiff ℝ (↑⊤) (u t))
(hv : ContDiff ℝ (↑⊤) (v t))
(hup : IsZ2Periodic (u t))
(hvp : IsZ2Periodic (v t))
(huTime :
MeasureTheory.IntegrableOn (fun (x : Homogenization.Vec 2) => v t x * deriv (fun (s : ℝ) => u s x) t) unitCube
MeasureTheory.volume)
(hvTime :
MeasureTheory.IntegrableOn (fun (x : Homogenization.Vec 2) => u t x * deriv (fun (s : ℝ) => v s x) t) unitCube
MeasureTheory.volume)
:
(∫ (x : Homogenization.Vec 2) in unitCube, u t x * amnrMaterial (streamVel φ) v t x) + ∫ (x : Homogenization.Vec 2) in unitCube, v t x * amnrMaterial (streamVel φ) u t x = (∫ (x : Homogenization.Vec 2) in unitCube, u t x * deriv (fun (s : ℝ) => v s x) t) + ∫ (x : Homogenization.Vec 2) in unitCube, v t x * deriv (fun (s : ℝ) => u s x) t
The material product pairing has exactly the same spatial integral as its temporal product pairing. The stream terms cancel by transport IBP.
theorem
AVenhance.Infra.Section4.iterate_material_time_mul
{b : ℝ → Homogenization.Vec 2 → Homogenization.Vec 2}
{q : ℝ → ℝ}
{h : ℝ → Homogenization.Vec 2 → ℝ}
{t : ℝ}
{x : Homogenization.Vec 2}
(hq : DifferentiableAt ℝ q t)
(hh : DifferentiableAt ℝ (fun (z : AmnrSpace) => h z.1 z.2) (t, x))
:
amnrMaterial b (fun (s : ℝ) (y : Homogenization.Vec 2) => q s * h s y) t x = deriv q t * h t x + q t * amnrMaterial b h t x
Material differentiation of a time coefficient times a space-time field. Only entrywise differentiability is needed; the drift is arbitrary.
theorem
AVenhance.Infra.Section4.iterate_material_matrix_contract
{b : ℝ → Homogenization.Vec 2 → Homogenization.Vec 2}
{Q : ℝ → Matrix (Fin 2) (Fin 2) ℝ}
{H : ℝ → Homogenization.Vec 2 → Matrix (Fin 2) (Fin 2) ℝ}
{t : ℝ}
{x : Homogenization.Vec 2}
(hQ : ∀ (i j : Fin 2), DifferentiableAt ℝ (fun (s : ℝ) => Q s i j) t)
(hH : ∀ (i j : Fin 2), DifferentiableAt ℝ (fun (z : AmnrSpace) => H z.1 z.2 i j) (t, x))
:
amnrMaterial b (fun (s : ℝ) (y : Homogenization.Vec 2) => ∑ i : Fin 2, ∑ j : Fin 2, Q s i j * H s y i j) t x = ∑ i : Fin 2, ∑ j : Fin 2, deriv (fun (s : ℝ) => Q s i j) t * H t x i j + ∑ i : Fin 2, ∑ j : Fin 2, Q t i j * amnrMaterial b (fun (s : ℝ) (y : Homogenization.Vec 2) => H s y i j) t x
The finite primitive/Hessian contraction obeys the material product rule. This is the algebra behind the first-increment half-square cancellation.