3401 — One Support Map Reduces the Balanced Occurrence Coend to the Trace Line
Question
Entry 3398 identifies instrument evaluation as a mate pairing. Does that balance law still permit several unrelated scalar readouts, or do the admitted occurrence maps select a universal quotient?
Balanced quotient
Write an instrument–state pair as the rank-one matrix
For every admitted occurrence map (f), the mate identity imposes
On (X), this is the balance relation
The finite coend is therefore the nine-dimensional matrix space modulo the span of the commutators
Exact census
The checker computes the relation rank and quotient dimension for five frozen map families.
| Admitted maps | Relation rank | Coend dimension | Generated algebra rank |
|---|---|---|---|
| cyclic transport (P) | 6 | 3 | 3 |
| (P) and incidence (F) | 6 | 3 | 3 |
| support projector (S) | 4 | 5 | 2 |
| (P) and (S) | 8 | 1 | 9 |
| (P,S,F) | 8 | 1 | 9 |
The incidence operator adds no algebra beyond cyclic transport in this representation. Cyclic transport alone therefore leaves three balanced readout channels.
One independently declared support map changes the result completely. The pair (P,S) generates the full (3\times3) matrix algebra, and its commutators span the eight-dimensional traceless subspace. The coend is one-dimensional.
Universal scalar
The trace annihilates every balance relation:
Since the quotient has dimension one, trace spans its dual and is the unique balanced scalar up to normalization.
For the matched source pair
the universal scalar is
Result
Static cyclic symmetry does not select a unique scalar readout. Cyclic transport plus one source-declared support operation does.
This supplies a precise role for support in the (3+2+1) architecture: support may create a mixed comparison defect, as in Entry 3385, while simultaneously making the balanced instrument quotient faithful and one-dimensional.
The two effects are compatible because Beck–Chevalley comparison and coend balance are different constructions.
Falsifier
The trace-line conclusion fails if the physical occurrence category does not admit the support map (S), or if its source-derived representation differs from the labelled route projector used here. Physical uniqueness therefore cannot be inferred from the algebraic quotient until that support operation is typed in the cosmological source.
Scope
This is a finite occurrence theorem. It does not prove that the physical Bunch–Davies instrument factors through this coend, and it does not authorize adding a support map solely to force scalar uniqueness.
Verification
Checker: research/benincasa/checkers/audit_occurrence_coend_readout.py.
Packet: research/benincasa/results/occurrence_coend_readout.json.
Allocator claim: seqclaim-8c8a636d61f1e9bfc3a0c6f9.
Epistemic graph event:
ev-000000007291-ce49a808-bd2a-4a87-adc7-7a913a7eb14b.