The Joint Observer Manifold: Field Geometry in the Relationship Between Observers

SFE-05.12b proved that a self-referential observer cannot detect its own field regime through its estimation residual — the information is structurally erased by the matched filter. SFE-05.13b showed that this information survives in position space, recoverable by a decoupled null-predictor channel. This work addresses the next question: where does field information live when no individual observer can access it? We construct a two-observer architecture in which both agents use null predictors (no adaptive estimation) and measure their cross-correlation in a sliding window. We show that the joint observer manifold — the geometry of the shared state space (xₐ, x_b, ρ_ab) — encodes field confinement strength k…