2235 — The Minimal Real Homogeneous Occurrence Adapter Is Gaussian Quadrupole Rank Two
Even full-momentum kernel
For a real boundary field, the Gaussian kernel must satisfy
The first anisotropic angular deformation is therefore quadrupolar, not linear. On a fixed momentum-magnitude shell in two dimensions, write
The isotropic coefficient supplies the trivial line, while span a rank-two angular port.
For the three equilateral directions, a scaled evaluation matrix is
Hence
Minimality
Entry 2234 proved that two additional directions are necessary. The quadrupole supplies exactly two, is even under momentum reversal, and is translation invariant. It is therefore the minimal conventional Gaussian source enlargement with the required representation type.
Evidence
- Entries 2233–2234
research/benincasa/checkers/quadrupole_gaussian_port.rs