The enumerated sampler used by the actual reduction #
The concrete binary encodings transport the sampling theorem to the exact finite ranges traversed by the reduction. The same index maps preserve unconditional source XOR-linearity.
theorem
Algebraic.Cutwidth.Extractor.Internal.sourceReductionSampler_xor
(n L : ℕ)
(x y : Fin n → Bool)
(i : Fin (sourceReductionOuterCount (matchedBlockSeedBits L)))
(z : Fin (sourceReductionCandidateCount (matchedBlockSeedBits L)))
:
sourceReductionSampler n L (fun (j : Fin n) => x j ^^ y j) i z = fun (j : Fin (sourceReductionSeedBits n L)) =>
sourceReductionSampler n L x i z j ^^ sourceReductionSampler n L y i z j
theorem
Algebraic.Cutwidth.Extractor.Internal.sourceReductionSampler_somewhereSampler
(n L : ℕ)
(positive : 0 < L)
(base : GrowingMatchedBlockRuntimeValid n (sourceReductionSeedBits n L) L 4)
(gamma : GammaBlockSizeGuard (matchedBlockSeedBits L))
:
SomewhereSampler (sourceReductionSampler n L) (2 ^ amplifiedMatchedSamplerEntropy L (sourceReductionSeedBits n L))
(sourceReductionSamplerError (matchedBlockSeedBits L)) (1 / 2)