Section 11 commutativity: pointwise scalar approximation #
Pointwise overlap terms ⟨Ψ, (I - G^x) ⊗ G^x Ψ⟩ controlling both sides of the G-stability
estimate, used as the base for the averaged scalar bound: the counterpart of
MIPRE/Background/LIDT/MIPStarRE/LDT/Commutativity/ScalarApproximation/Pointwise.lean in the
port of planning/c6b-plan.md (milestone M7, section "Port conventions").
The overlap term is strategy.state.ev (strategy.state.L (1 - T) * strategy.state.R T) on the
symmetric model of the strategy, and gCommStability_pointwise_sum_bound_core takes the model
S : SymModel 𝔓 K as an explicit first argument in place of the vendored state ψ. The
vendored hypothesis strategy.permInvState passed to qBipartiteSSCDefect_eq_half_qSDD_of_proj
and Preliminaries.twoNotionsOfSelfConsistencyAfterEvaluation is gone with those lemmas'
hperm; the one swap use left here is S.ev_L_eq_ev_R in gCommStability_ssc_point, in place of
strategy.permInvState.swap_ev.
The proofs are shorter than the vendored ones. The vendored self-adjointness of G^x through
Matrix.PosSemidef is IsSelfAdjoint.of_nonneg; the entrywise Kronecker identity
(1 - T) ⊗ I = I ⊗ I - T ⊗ I of gCommStability_ssc_point is S.leftTensor_sub and
map_one; and the sums over outcomes in gCommStability_pointwise_sum_bound_core and
gCommStability_ssc_point collapse through the keystone's opTensor_sum_left_univ and
opTensor_sum_right_univ.
Not ported #
Every declaration of the vendored file has a counterpart here.
References #
In LionSR/MIPStarRE at commit 507e8122, not in this repository:
references/ldt-paper/commutativity-G.texblueprint/src/chapter/ch08_commutativity.tex
The common overlap term ⟨Ψ, (I - G^x) ⊗ G^x Ψ⟩ controlling both
stability estimates.
Equations
Instances For
The slice self-consistency defect of G is at most zeta / 2.
Slice strong self-consistency transfers to the evaluated point family.
The paper invokes the slice self-consistency item after postprocessing a slice
measurement by the predicate g(truncatePoint u) = a. This lemma makes that
implicit data-processing step explicit: projectivity converts the left/right SDD
hypothesis into bipartite strong self-consistency with loss 1/2,
question-dependent postprocessing converts it back to left/right SDD with the
compensating factor 2, and uniform reindexing
Point params.next ≃ Point params × Fq params averages the height coordinate.
A sandwiched product of two submeasurements is controlled by the overlap of
the right-hand total with its complement. The vendored state ψ is the symmetric model S.
A single stability-one summand is controlled by replacing the inner evaluated slice sandwich with the corresponding evaluated point outcome.
The full stability-one defect is bounded by the overlap term for the
target slice measurement G^y.
The overlap term at x is bounded by the bipartite SSC defect of G x.