CubeSetAtMeanValueStream #
Ported from scottnarmstrong/Superdiffusion at 7f20476385d4af418f110303085ad0740c9eba46. Module imports, support namespace and local option directives adapted for Lean Pool.
The exit mean-value property on a translated triadic cube for the stream field #
CubeSetAtMeanValueConsumer.lean carries a global small-contrast datum, because the exit
decomposition it invokes does. The stream field of the model supplies no such datum, and the
coefficient-generic C₀ barrier comparison replaces it. This file is the small-contrast-free
copy of that chain on cubeSetAt y n: the same statements, with the small-contrast datum removed
from every hypothesis list and the analytic data fixed to the stream field of the model.
The analytic half — the Green potential of the cube, the harmonic part, and its H¹ packaging —
carries no process hypothesis at all and is shared verbatim with the small-contrast route; only
the four process statements and the two consumer lemmas are repeated here.
The assumptions are those of the coefficient-generic comparison: the resolvent carrying the
process, its one-point regularity data, conservativity of the live kernel semigroup, the
bounded-measurable identification of the kernel resolvent with the analytic minimal resolvent,
and the operator identification against the C₀ barrier resolvent of the stream field.
The harmonic part of a resolvent datum on a translated triadic cube is represented by the exit distribution, for the stream field.
A difference of harmonic parts on a translated triadic cube is represented by the exit distribution, for the stream field.
A uniform limit of differences of harmonic parts on a translated triadic cube is represented by the exit distribution, for the stream field.
The harmonic part of a stream resolvent datum on a translated triadic cube is the whole-space harmonic part of that datum there.
The H¹ package of a harmonic part on a translated triadic cube, for the stream
field.
A weakly a-harmonic function on a translated triadic cube with a continuous boundary
datum vanishing at infinity has the exit mean-value property, for the stream field.
The instantiation shape on a translated triadic cube, for the stream field. When the
boundary datum is a smooth compactly supported function b, the continuous datum vanishing at
infinity and its H¹ realization on the cube are both supplied by b itself, and the only
inputs left are the weak harmonicity of the observable inside the cube, its continuity there,
its agreement with b outside, and its trace.