Integrals of fields supported in a smaller cylinder #
The product-coordinate integral of a field supported inside a target cylinder equals its set integral on that cylinder.
theorem
ESS.bu_target_setIntegral_eq_product_integral
{Ω : Set CKN.Foundation.Parabolic.Vec3}
{I : Set ℝ}
{K : Set CKN.Foundation.Parabolic.ParabolicPoint}
(hKsub : K ⊆ CKN.spaceTimeSet Ω I)
(F : CKN.Foundation.Parabolic.ParabolicPoint → ℝ)
(hzero : ∀ z ∉ K, F z = 0)
:
∫ (z : CKN.Foundation.Parabolic.ParabolicPoint) in CKN.spaceTimeSet Ω I, F z = ∫ (q : CKN.Foundation.Parabolic.Vec3 × ℝ), F (CKN.Foundation.Parabolic.parabolicHomeomorph.symm q)
For a scalar integrand supported in a subset of a target cylinder, the target set integral is the unrestricted product-coordinate integral.