Weak divergence and curl identities along the bootstrap #
Restriction of weak identities to smaller sets, and the propagation of the weak divergence-free
condition and of the weak antisymmetric-derivative identity to weak derivatives. These supply the
inputs of the div–curl recovery at each level of thm:vorticity-regularity.
A weak identity between integrands supported where the test is supported restricts to every smaller set.
A spatial derivative of a test vanishes off its support.
A weak derivative identity restricts to smaller sets.
A weak heat equation restricts to smaller sets.
A weak divergence-free condition restricts to smaller sets.
The velocity satisfies the weak antisymmetric-derivative identity with the vorticity of its weak gradient.
Moving a weak derivative onto a derivative of the test: ∫ Y' ∂ₐψ = -∫ Y ∂ₐ(∂ₘψ).
Weak derivatives of a weakly divergence-free field are weakly divergence free.
Weak derivatives of a field satisfying the weak antisymmetric-derivative identity satisfy it with the derivative of the antisymmetric data.