scpn_phase_orchestrator.nn.chimera contract

Purpose: - Provide differentiable chimera diagnostics (local_order_parameter, chimera_index, detect_chimera) for coupled oscillator states.

Public contract: 1. Local order parameter output is shape-stable and bounded in [0, 1]. 2. Chimera index returns finite scalar variance metric. 3. Coherent and incoherent masks from detect_chimera remain disjoint for ordered thresholds (coherent_threshold > incoherent_threshold).

Verification: - tests/test_nn_chimera.py::TestLocalOrderParameter::test_range - tests/test_nn_chimera.py::TestChimeraIndex::test_scalar_output - tests/test_nn_chimera.py::TestDetectChimera::test_threshold_masks_disjoint

Production interpretation

This contract supports state diagnostics in mixed-coherence regimes. In practice, chimera indicators are used as an early warning when the system is moving from a globally synchronized phase toward fragmented structure.

By keeping output semantics bounded and threshold masks disjoint, supervisory logic can consume the diagnostic signals without introducing contradictory interpretation paths.

Why this contract matters in operations

• In high-asset environments, partial synchrony is often operationally important. You need to know where coherence is localised before applying global control.
• The disjoint-coherence invariant prevents a single oscillator from being simultaneously tagged as both coherent and incoherent at one threshold pair, which protects downstream action logic from ambiguous telemetry.
• Bounded outputs reduce the chance that monitor fusion layers accidentally interpret numerical drift as structural drift.

Operator interpretation

Partial synchrony diagnostics are often used in escalation decisions where global coherence is not yet a sufficient signal. Teams may still need a coherent subgroup to stabilise while preserving other modes that carry important structure.

This contract therefore serves as a semantic guard around ambiguous transitions: it gives strict rules so alerting and supervisor logic can separate mixed regimes without forcing a binary interpretation too early.

The bounded and disjoint outputs are what make it safe to use in chained monitoring pipelines, because each alarm signal maps cleanly to a single interpretation.

Operational overview

The contract is useful whenever a control stack needs a stable indicator for mixed synchrony rather than a binary "locked vs. unlocked" answer.

In these conditions, chimera_index and detect_chimera provide interpretable telemetry for partial-order states. This is frequently where physical systems enter practical instability first: not as a global meltdown, but as a shift into patchy coherence.

Operational value for mixed-order regimes

This contract is intended for environments where global coherence is not the only stable state. It gives an explicit way to monitor localized structure while avoiding ambiguous alarms when the system is not fully synchronized.

Deployment guidance:

• Keep threshold pairs explicit (coherent_threshold > incoherent_threshold).
• Use local order and index outputs together; one is a fine-grained trace, the other is a scalar summary.
• Include chimera outputs in escalation bundles before switching from advisory to command channels.

Why this matters in review and handoff

• local_order_parameter provides a bounded local coherence signal that can be compared across layers and domains.
• chimera_index collapses regional coherence asymmetry into a single scalar for alert dashboards.
• Threshold masks with explicit disjoint constraints reduce ambiguity at escalation points where operator policy decisions are made.