3530 — The Physical Shape Insertion Has a Nonzero Anti-Invariant Branch Costalk
Hard-to-vary claim
At the representative cyclic (A_1) point, the ordered reduction of the two native triple occurrences has zero marked (s_{12})-residue but a nonzero anti-invariant Cayley--Menger branch costalk. In the source normalization, its two sheet values are (-17/6) and (17/6).
Ordered calculation
Use
with the orientation inherited from ((a,b,c)). The coordinate Jacobian is
Sum the two source occurrences carrying the complete local wall triple before reduction. Remove the cubic (x)- and (y)-poles by the canonical second derivatives. The exact remaining coefficient is
The factor (z^5/(z^2)^{5/2}) has opposite values on the two normalized square-root sheets. Including the coordinate Jacobian gives
Thus the anti-invariant difference is (17/3).
Typing consequence
No (1/z) pole remains after the proper-face reduction. Hence this is not a ternary marked-wall residue. It is a finite costalk value on the rank-one anti-invariant (A_1) branch object. This distinction explains why the class was invisible in the proper marked-wall circuit census.
Interpretation boundary
The coefficient class is nonzero. A physical observable is not yet proved: the Bunch--Davies relative cycle has not been specialized to this local costalk, and no intersection pairing has been computed.
Next falsifier
Derive the source relative-cycle specialization at the cyclic (A_1) point. Track orientation and deck character, then pair it with the costalk vector ((-17/6,17/6)). A deck-even cycle gives zero; a source-authorized deck-odd component activates the class.
Evidence
research/benincasa/compute_shape_branch_mixed_costalk.py;research/benincasa/results/shape-branch-mixed-costalk.json.
Allocator claim: seqclaim-8cdeaf90ab2c0509047f9c04.