Space-time weak vorticity equation #
Compact tests are localized to CKN local boxes, where the suitable solution provides almost-everywhere spatial weak gradients.
A compactly supported integrand has the same integral over any set that
contains its support and over its support (manuscript
lem:vorticity-weak-eq).
A CKN scalar test remains a test after taking a spatial derivative.
A CKN scalar test remains a test after time differentiation.
The space-time set of a CKN local box is null-measurable for the
parabolic volume measure (manuscript lem:vorticity-weak-eq).
Suitable velocity components multiplied by a compact test are integrable
on every local box (manuscript lem:vorticity-weak-eq).
Suitable weak-gradient components multiplied by a compact test are
integrable on every local box (manuscript lem:vorticity-weak-eq).
Fubini's theorem in the native parabolic carrier identifies a local space-time integral with its time-first iterated integral.
Testing the suitable momentum equation with the curl of a compact test
field removes the pressure and zero force terms (manuscript
lem:vorticity-weak-eq).
The curl-tested momentum identity can be restricted to the compact support
of the test curl (manuscript lem:vorticity-weak-eq).