The Orbit-Paired Plus Source Is a Dual-Number Subcomplex
The generator-filtered complex of Entry 514 admits a source-level deck
diagonalization. For a labelled monomial a^i b^j in the minus lattice,
let x_- and x_+ denote its two orbit-labelled copies. The plus
eigenvector is
where
The deck involution fixes u, acts on scalar coefficients by a -> -a,
and acts on the gradient frames with characters (-,+,+). Consequently
the eigenspace decomposition is R=Q[u]/(u^2)-linear.
The executable checker forms every plus eigenvector before applying the
differential. Its scalar image is deck invariant, its gradient image is
invariant after including the frame characters, and its u-multiple
remains invariant. The verified plus source ranks over R are
Thus the plus sector is an actual dual-number subcomplex, not a projection of target rows after column admission. The next computation may now build the finite matrices of this plus complex and compute its genuine middle homology and derived specialization.
Evidence
research/benincasa/check_soft_axis_labelled_total_truncation.py- Entries 514 and 105.