Source-boundary role-register handoff: completion lemmas #
The completion and line-169 transport lemmas of the two-space tail of the main theorem: the
counterpart of
MIPRE/Background/LIDT/MIPStarRE/LDT/Test/MainTheorem/SourceRoleRegister/Completion.lean in the
port of planning/c6b-plan.md (milestone M13, section "Port conventions").
Everything here is two-space. The vendored state is on ιA × ιB, with Alice's measurements on
ιA and Bob's on ιB. Here it is a bipartite model M : MIPRE.BipartiteModel 𝒞 𝒜 ℬ with a unit
vector, hψ : ‖M.ψ‖ = 1, and for the three theorems the model strategy.state of a two-space
ProjStrat, with strategy.isNormalized. The translation is that of
Co/Test/MainTheorem/TwoSpace.lean:
- the vendored
ConsRel ψ 𝒟 A B δisbipartiteConsError M 𝒟 A B ≤ δ(M2's two-space defect); SDDRel ψ 𝒟 (leftPlacedSubMeas A) …is(TwoSpace.vecState M hψ).SDDRel 𝒟 (TwoSpace.leftPlacedSubMeas M A) …, a relation of the vector state onM.H →L[ℂ] M.H;ev ψ (leftTensor X)is(TwoSpace.vecState M hψ).ev (TwoSpace.placeA M X), and the right forms likewise throughplaceB. The same-space lemmas of CoPreliminaries(completion_self_distance,constFamily_sdd_unit,questionSDD_triangle,question_easyApproxFromApproxDelta,right_match_gap_abs_le_sqrt_qSDD,stateDependentDistanceRel_triangle_three) apply to the placed families as they are, andTwoSpace.simeqToApprox_heterogeneousis the two-spacesimeqToApprox_heterogeneous.
The two matrix bookkeeping lemmas qSDD_leftPlaced_completeAtOutcome_eq and
qSDD_rightPlaced_completeAtOutcome_eq, entrywise Kronecker computations in the vendored file,
are here the fact that a placement commutes with completion (placeA M 1 = 1 and map_sub).
They take any vector state V : VecState M.H, since they use only the placements.
Departure: completion takes hM : M.IsFinitePair. The vendored
Preliminaries.completeAtOutcomeProj needs a C⋆-algebra, and 𝒜, ℬ are abstract star-ordered
⋆-algebras; so a projective submeasurement is completed through
TwoSpace.completeAtOutcomeProjA/B, which complete in the commutant that a finite pair
identifies each algebra with. The lemmas and theorems that complete therefore take
hM : M.IsFinitePair (hM : strategy.state.IsFinitePair for the theorems), placed right after the
state and, where it is taken, its normalization hψ. The completion's submeasurement is completeAtOutcome P a0
(TwoSpace.completeAtOutcomeProjA_toSubMeas), so nothing else changes.
completedProjectiveConsistency_ofFullConsistency completes nothing and takes no hM.
Departure: imports. The vendored file imports SourceRoleRegister/Core; this one imports Co
Test/MainTheorem/ProjectiveConsistency/Evaluation (with TwoSpace) and the M8 files
MakingMeasurementsProjective/{Orthonormalization, ProjectivizationChain/Basic}, which bring the
vendored classical constants orthonormalizationError and orthonormalizeAndCompleteError. No
declaration of the vendored Core is used, so the Co Core is not imported.
The constants are the vendored ones: orthonormalizationError ζ for the orthonormalization,
orthonormalizeAndCompleteError ζ after completion, ζ + √(orthonormalizationError ζ) for the
repaired line-169 consistency and 6ζ + 6ζ₂ for the line-156 distance.
New here #
bipartiteConsError_constFamily_unit: the two-space defect of constantUnit-indexed families is the defect of their members (the two-space form ofPreliminaries.constFamily_sdd_unit, which the vendored proofs unfold bysimpat every use).
Not ported #
Every declaration of the vendored file has a counterpart here.
The two-space defect of constant Unit-indexed families under the uniform distribution is
the defect of their members.
Completing after left placement agrees with left placement after completing the local
submeasurement: a placement maps 1 to 1 and commutes with differences.
This is the bookkeeping needed to apply the completion-distance identity on M.H while returning
the local completed projective measurement of the paper.
Completing after right placement agrees with right placement after completing the local submeasurement.
If the missing left total of a projective submeasurement is small on the state, then its completion is close to it after left placement.
Right-placement counterpart of qSDD_completeAtOutcomeProj_leftPlaced_le_of_total_gap.
A left-placement distance estimate controls the loss in two-space matching mass against a complete measurement of the second player.
A right-placement distance estimate controls the loss in two-space matching mass against a complete measurement of the first player.
The two-space matching mass against a complete measurement of the second player is at most the expectation of the placed total of the other submeasurement.
The two-space matching mass against a complete measurement of the first player is at most the expectation of the placed total of the other submeasurement.
Completing a projective submeasurement of the first player can only increase its two-space matching mass against a fixed submeasurement of the second player.
Completing a projective submeasurement of the second player can only increase its two-space matching mass against a fixed submeasurement of the first player.
Combine cross consistency and the first player's orthonormalization closeness into the completion estimate for the left placement.
Second-player counterpart of completedCloseness_left_of_consistency_and_sdd.
The first player's repaired line-169 consistency after completing the projective submeasurement.
This is the two-space analogue of the paper's Q^A_g ⊗ I ≃ I ⊗ G^B_g step, with the checked
repaired loss ζ + √(orthonormalizationError ζ).
The second player's repaired line-169 consistency after completing the projective
submeasurement: the two-space analogue of the role-reversed relation G^A_g ⊗ I ≃ I ⊗ Q^B_g.
The strategy-level theorems #
Complete the two projective submeasurements obtained after the line-130 cross-consistency estimate to projective measurements, with the placed state-dependent-distance estimates the paper requires.
Paper origin: references/ldt-paper/inductive_step.tex:143-149. Consistency bounds the mass
missing from each projective submeasurement once the orthonormalization distance is charged by
Cauchy–Schwarz, and the completion residual contributes at most that mass.
Complete the two projective submeasurements and derive the two repaired polynomial line-169 consistency relations.
Paper origin: references/ldt-paper/inductive_step.tex:167-172. The paper applies
triangle-sub after the completion estimates; the statement here is the checked repaired version,
in which the replacement of G_A by Q_A and of G_B by Q_B is charged directly from the
pre-completion orthonormalization distance, giving the error ζ + √(orthonormalizationError ζ).
The line-156 projective consistency estimate after completing both polynomial submeasurements.
Paper origin: references/ldt-paper/inductive_step.tex:150-157. The consistency of G_A, G_B
gives the distance 2ζ of their placements (TwoSpace.simeqToApprox_heterogeneous), which
telescopes through the two completion-distance estimates for Q_A and Q_B.