R12 Cross-Domain Fault-Channel No-Go

Status: three candidate mechanisms rejected before neural implementation. No data generation, fit, accelerator work, or Shohin capability claim is authorized.

CPU protocol: R12-CROSS-DOMAIN-FAULT-CHANNEL-NO-GO-v1

1. Motivation

Shohin's measured failure is not a generic absence of useful internal signal. The protected raw-300k model shows:

• natural-language compilation: 0/6;
• oracle-compiled frozen DRS transitions: 28/34;
• terminal serialization: 2/6.

Other frozen boards show the same asymmetry: local transitions can be strong, while autonomous operation selection, state transport, halting, correction, and state consumption fail. Cross-domain inspiration is useful only if it attacks that measured error channel and survives a resource-matched collapse test.

The search considered four source domains:

1. biological error-correcting population codes;
2. paired forward/inverse motor models;
3. conservative and reversible dynamics; and
4. hippocampal replay and compositional state construction.

These are real scientific precedents, not novelty claims. Relevant primary sources include fault-tolerant neural networks from biological error-correction codes, tandem forward and inverse internal models in cerebellar motor learning, and compositional memory construction through hippocampal replay.

2. Fault-neighborhood lemma

Let r be one causal state, E(r) its retained encoding, and F the admitted fault family. Define its observed fault neighborhood

N(r) = { f(E(r)) : f in F }.

Lemma

Exact autonomous recovery is possible only if

N(r) intersect N(s) = empty

for every pair of distinct causal states r != s that require different future behavior.

Proof

If an observed configuration y lies in both neighborhoods, then one admissible history requires recovery to r and another requires recovery to s. A deterministic decoder receiving only y cannot return both. A randomized decoder cannot be exact on both. Therefore exact recovery requires disjoint neighborhoods or additional information that distinguishes the origin.

Disjoint neighborhoods are coding redundancy. Extra origin information is retained source, provenance, a checkpoint, or another state channel. A selector that supplies missing semantic information is an oracle. Reversible transport can permute overlapping neighborhoods but cannot make them disjoint. A contracting projection is a decoder; if it merges future-distinguishable clean states, it violates causal separation.

The lemma does not reject error-correcting representations. It prevents them from being credited with semantic information they do not contain.

3. Candidate A: Triadic Efference Commit

Proposed object

A controller, executor, and forward model independently propose a next state. The machine commits only when two of three agree. Output text is downstream of the committed state and cannot modify it.

z_t = (x_t, u_t^C, u_t^E, u_t^F, syndrome_t)
u_t^i = F_i(x_t, event_t)
x_(t+1) = majority(u_t^C, u_t^E, u_t^F)

Finite result

For the complete one-bit transition x' = x xor a, the CPU board checks all four state/action pairs and every one-of-three lane fault: 12/12 are recovered. The decoder is byte-for-byte ordinary three-copy repetition-majority decoding.

Two disagreeing lanes cannot identify the faulty member. Observation (0,1) is consistent both with truth zero and a fault in lane one, and with truth one and a fault in lane zero.

When all lanes share the wrong semantic action, majority accepts the wrong codeword in 4/4 cases. This matches Shohin's common-mode operation-selection failure rather than repairing it.

Verdict

REJECT as a new mechanism. A favorable three-copy recurrent control receives the same parameters, retained bits, examples, and compute and has identical behavior. Redundancy may remain an engineering control after semantic compilation works, but it is not the missing compiler.

4. Candidate B: Shadowed Variational Transport

Proposed object

Each event induces a reversible, invariant-preserving state action. A shadow trajectory and conserved quantities are intended to prevent compositional drift.

z_t = (q_t, p_t, constraints_t, invariants_t)
z_(t+1) = Phi_event(z_t)

where every Phi_event is invertible. A separate observer reads the endpoint.

Finite result

The CPU board uses the determinant-one cat map

A = [[2, 1],
     [1, 1]] mod 5.

It enumerates all 25 states, all 24 nonzero perturbations, and ten recurrent steps: 6,000 perturbed/clean comparisons. No nonzero error ever contracts to zero because every power of A is invertible.

Shadowing guarantees at most that a perturbed trajectory is a valid nearby trajectory. It does not identify the trajectory belonging to the committed history. A projection that chooses that history is a noninvertible decoder or uses extra provenance. Reversible realization of an irreversible task must retain discarded information in an ancilla or archive.

Verdict

REJECT as an error-correction mechanism. A matched recurrent controller can apply the same reversible map with identical state, precision, depth, and compute. Conservation can preserve information but cannot supply missing semantic selection or remove ambiguity.

5. Candidate C: Consolidated Relation-Syndrome Atlas

Proposed object

Short event blocks enter a fast trace. Replay applies known algebraic relations, checks a syndrome, commits a canonical block action into slow causal state, and retires the raw trace. Late queries read only the slow state.

Finite result

The CPU board uses the symmetric group S3 with adjacent transpositions s and t. It verifies the involution and braid relations

s^2 = identity
t^2 = identity
sts = tst.

The complete relation atlas has six states and twelve state-generator pairs. It is exactly the ordinary tied six-state recurrence in canonical coordinates.

The board then removes one of the twelve pairs and constructs a patched updater that is exact on all eleven admitted pairs. It passes every observed transition but fails a word that reaches the omitted pair; at least one late query separates the patched endpoint from the exact endpoint.

Retaining the raw trace is retrieval. Updating the atlas within an episode is fast weights. Host canonicalization is external symbolic execution. A complete fixed atlas is the recurrent transducer itself.

Verdict

REJECT as a distinct reasoning primitive or finite identification protocol. Replay may allocate training examples usefully, but completeness or a uniform generalization theorem is still required. Relation consistency on an incomplete finite board does not identify the missing transition.

6. Resource and claim boundary

The mandatory resource vector remains

(parameters, retained bits, precision, source bytes,
 training examples, oracle calls, training FLOPs, inference FLOPs,
 sequential depth, external memory, external execution).

Each candidate has a favorable conventional realization preserving that vector:

The three mechanisms therefore receive 0/3 survival at the exact-collapse gate. This result does not prove that every possible biological, physical, or mathematical inspiration fails. It proves only these three named reductions.

7. Consequence for Shohin

The next high-value measurement is error-channel attribution, not generic redundancy:

1. freeze a source and correct typed program;
2. separately intervene on opcode, operand boundaries, local transition, carry, halt, and serializer state;
3. measure whether errors are independent across components or common-mode;
4. permit coding redundancy only for empirically independent corruption; and
5. direct new parameters and examples toward semantic compilation when lanes agree on the same wrong program.

This supports the current compiler/executor/serializer decomposition but grants no VAMT neural authority. The full-program VAMT CPU board is reviewed separately. A compiler failure cannot be rescued by calling an exact executor "reasoning," and an exact executor cannot be blamed for a wrong compiled program.

8. Reproducibility and authorization

The executable evidence is:

• pipeline/cross_domain_fault_channel_falsifier.py
• pipeline/test_cross_domain_fault_channel_falsifier.py
• generated report scratchpad/cross_domain_fault_channel_no_go_v1.json

The report must be deterministic, refuse overwrite, label all three candidates rejected, and keep neural_preregistration_authorized = false.

Current authority:

CPU no-go mechanics:         allowed
Neural preregistration:      NO-GO
Neural implementation:      NO-GO
Data generation or fitting: NO-GO
H100 work:                   NO-GO
Novelty/reasoning claim:     NO-GO