Documentation

CsdLean4.Empirical.CSD.Ozawa

Empirical/CSD: Ozawa readout cannot reproduce the stroke from base ray and pointer alone #

Category: 3-Local (CSD-side companion to Empirical/QM/Ozawa.lean).

Empirical/QM/Ozawa.lean proves Ozawa's error–disturbance relation for any OzawaData — four symmetric operators on one inner-product space with the two "out" operators commuting. The question here is whether such data, encoded from the base ray and pointer alone, can reproduce the record-layer stroke's pointer output at every arena state.

★ no_ozawa_model_of_jointLift rules out this factorisation for a joint lift when ε > 0 and two distinct outcomes at the same base ray have rates at least 2ε. The encoding e : LF4.CPN N × Pointer N → T omits the register coordinate. States with the same base ray and pointer can therefore have different stroke outputs. The theorem does not address encodings that include the register or models that reproduce only outcome statistics.

Why this is the honest twin, and not a transport bundle #

The obvious move would be a "volume-ratio reading" of ε and η on the pattern of Empirical/CSD/Uncertainty.lean. Two reasons that would be wrong, both recorded in specs/ozawa-scoping.md §5:

So the twin follows WAY brick 1 instead (Empirical/CSD/WignerArakiYanase.lean): state the scope as a theorem at the IsJointLift level. This file is a corollary of no_joint_hilbert_map, not a parallel capstone (CONVENTIONS §8.3b) — the general theorem does the work, and this instantiation says what it means for this brick.

⚠️ Honest scope #

References #

Empirical/QM/Ozawa.lean (OzawaData, ozawa_error_disturbance); Empirical/CSD/WignerArakiYanase.lean (no_joint_hilbert_map, brick 1 of specs/way-theorem-scoping.md, whose pattern this follows); specs/ozawa-scoping.md §5 (why this is a scope theorem rather than a volume-ratio twin); specs/residues.tsv (R-015); specs/BACKLOG.md row B.

theorem CSD.Empirical.CSDBridge.Ozawa.no_ozawa_model_of_jointLift {N : ℕ} {c : RecordLayer.ContextField N} {ε : ℝ} {Φ : RecordLayer.PointerArena N N → RecordLayer.PointerArena N N} (h : RecordLayer.IsJointLift c ε Φ) (hε : 0 < ε) {p : LF4.CPN N} {j k : Fin N} (hjk : j ≠ k) (hj : 2 * ε ≤ c.rate p j) (hk : 2 * ε ≤ c.rate p k) {T : Type u_1} [NormedAddCommGroup T] [InnerProductSpace ℂ T] (d : Ozawa.OzawaData T) (e : LF4.CPN N × RecordLayer.Pointer N → T) (r : T → RecordLayer.Pointer N) :
¬∀ (y : RecordLayer.PointerArena N N), (Φ y).2 = r (d.aOut (e (y.1.1, y.2)))

★ No exact Ozawa readout from base ray and pointer alone.

For a joint lift with ε > 0 and two distinct outcomes of rate ≥ 2ε at the same base ray, the stroke's pointer image cannot agree at every arena state with r (d.aOut (e ·)), where e encodes only (base ray, pointer) into an inner-product space T. This holds for every OzawaData on T and every readout r: the omitted register coordinate selects between different outputs from identical (base ray, pointer) data.

This rules out the stated factorisation, not all measurement models or definitions of Ozawa error and disturbance on an extended model. Encodings that retain the register and agreement only at the level of outcome statistics are outside this theorem's scope.

A corollary of no_joint_hilbert_map with U := d.aOut, not an independent result.