An explicit local hidden-variable model with a stochastic two-channel detector is constructed that reproduces the quantum correlation E(a,b) = −cos(a−b) for the singlet state. The model uses only: (i) a shared classical phase λ ∈ [0,2π), uniformly distributed; (ii) Malus-law detection probabilities; (iii) two independent binary channels per detector. The standard Bell ±1 encoding is shown to be a lossy compression of the two-channel output, and the CHSH parameter |S| = 2√2 emerges from this encoding without any non-local mechanism. The raw (unnormalised) correlation satisfies CHSH (|S| = √2 ≤ 2); the normalised (Pearson) correlation violates it (|S| = 2√2 > 2), without any change in the underlying physical model. The CHSH test, as currently implemented, cannot distinguish between an entangled quantum source and the classical model presented here.
Roberto Pavani (Thu,) studied this question.
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