Revisiting factorability and indeterminism
  Perhaps it is not completely superfluous to remind that Clauser-Horne factorability, introduced in [1], is only necessary when \lambda, the hidden variable (HV), is sufficiently deterministic: for {M_i} a set of possible measurements (isolated or not by space-like intervals) on a given system, the most general sufficient condition for factorability on \lambda\ is obtained by finding a set of expressions M_i=M_i(\lambda,\xi_i), with {\xi_i} a set of HV's, all independent from one another and from \lambda. Otherwise, factorability can be recovered on \gamma = \lambda\ \oplus\ \mu, with \mu\ another additional HV, so that a description M_i=M_i(\gamma,\xi_i) is again found: conceptually, this is always possible; experimentally, it may not: \mu\ may be unaccessible or even its existence unknown (and so, too, from the point of view of a phenomenological theory). Results here may help clarify our recent post in [6]. 
David Rodriguez
quant-ph math-ph math.MP