A cycle certificate must retain its intermediate steps

The source's deriver cycle requires more than the original four-conjunct selfDerivation target. It requires a nonzero apply path whose intermediate steps preserve simulation. The six-form model satisfies every current logical clause and the original target while having no nonzero preserving derivation path at all. Thus even proving that target would leave a source correspondence obligation about the cycle's actual execution.

The new certificate and lemmas in lean4/Hypermath/L3Ordinatics.lean expose this distinction. They preserve the original target and add no native axiom. They do not claim an inhabitant of the stronger certificate type.

Source requirements

The relevant source files are preserved unchanged:

Here simulation is the source relation Simulation; it is not silently replaced by equality, congruence, or similarity. Length counts retained edges and has no physical unit. A path's endpoint relation and its intermediate-edge relations are distinct propositions.

Constructive certificate interface

SimulationStep(x,y) means both y = f2f(x) and Simulation(y,x). SimulationEntry(x,y) is a finite Trace of those witnessed edges. simulationEntryToDEntry uses the existing filtration clause to turn each simulation edge into a congruence-preserving edge. Its length theorem proves that this conversion retains the number of steps.

DriverCycleWitness retains:

  1. a SimulationEntry from deriver to f2f(f2f(deriver));
  2. a proof that this particular path has exactly two edges;
  3. the endpoint closure driverCycleClaim.

driverCycleWitnessOfSteps constructs this certificate from proofs of both specific simulation steps and endpoint closure. Its existence theorem checks that the constructor actually produces an inhabitant from those premises. The constructor is noncomputable because native forms and application remain uninterpreted source parameters; this is not a newly executable native checker.

witness_has_two_D_steps derives a two-edge congruence-preserving trace from the certificate. selfDerivationOfWitness derives the original target from its closure field. The converse is not supplied and fails in the model below. The weaker driverInDAtSimulationOfCycle interface remains available with its original meaning: a zero-step self-read together with endpoint simulation. It does not return this stronger certificate.

The type uses Lean's dependent types and inductive traces as infrastructure. Encoding these witnesses as native forms and deriving their ranked acceptance remain additional obligations; the existence of this type does not discharge them.

A target-satisfying model with no preserving steps

In lean4/FiniteActionCountermodel.lean, application has the cycles a1 -> a2 -> a1 and b0 -> b1 -> b2 -> b0, with a0 -> a1. The deriver is a1, and simulation is equality. Consequently applying twice returns the deriver to itself and the original target holds.

Congruence is equality of class labels. The respective labels of a0,a1,a2,b0,b1,b2 are 0,1,2,3,1,2. Every apply edge changes its class label. Therefore no apply edge preserves congruence, even though the deriver's two-step endpoint returns to its original label and form.

The four added checked results establish:

Declaration Result
no_preserving_step No pair of forms satisfies the interpreted DStep
every_D_entry_is_empty Every interpreted DEntry has length zero
no_nonzero_D_entry No positive-length interpreted DEntry exists
full_clauses_and_target_without_nonzero_D All 38 clauses and the original self-derivation target hold together with that absence

The first three results use Lean's propositional extensionality. The combined result additionally uses quotient soundness through the existing model. None uses an admission or adds a native logical clause. This is a result about the current formalized clauses, not a refutation of every possible source-native realization.

The finite successor obstruction

Let E(n) = finiteApplyPosition(n). The named proposition FiniteSuccessorAgreement is

[ \forall n\in\mathbb N,\quad \operatorname{ordinalSucc}(E(n))=E(n+1). ]

It is a proposed correspondence law, not an assumption added to the foundation. If it holds and x = E(n), then ordinalSucc(x) = f2f(x). The existing axSuccExtends clause gives not Simulation(ordinalSucc(x),x), hence not Simulation(f2f(x),x).

no_simulation_step_at_finite_of_successor_agreement checks that argument. simulation_trace_from_finite_is_empty extends it to every simulation trace starting at a finite ground form: a nonempty trace would already require the forbidden first edge. It follows that

[ \operatorname{FiniteSuccessorAgreement}\ \land\ \operatorname{finiteApplyFromGround}(\operatorname{deriver}) \quad\Longrightarrow\quad \neg\operatorname{Nonempty}(\operatorname{DriverCycleWitness}). ]

no_driver_cycle_witness_at_finite_successor proves this implication. The three obstruction lemmas use source parameters and axSuccExtends, with no admitted proof, classical choice, or new logical clause. They do not establish either antecedent from the current 38 clauses.

Consequence for the intended architecture

A source-adequate construction must specify how arithmetic successor, execution of the checker, and rank-changing representation act on their respective objects. If they use the same apply operation on finite ground forms with the successor equation above, its individual steps cannot also preserve the source's strict simulation relation. Endpoint return after two steps does not remove this obstruction.

A proposed separation by type, rank, or observation requires actual source rules and a preservation theorem. Merely naming separate layers, weakening simulation to similarity, or postulating acceptance does not supply that construction. The remaining work is to derive the appropriate operational rules, retain their records, and prove arithmetic soundness and truth coverage.

The audit now binds 45 production milestones and 22 finite-action model reports, alongside the existing groups. The inventory remains 67 assumptions and 11 admission sites. The strict original target, source adequacy, and recursive arithmetic completeness gates remain unresolved.