Maudlin has claimed that no local theory can reproduce the predictions of standard quantum mechanics that violate Bell’s inequality for Bohm’s version (two spin-half particles in a singlet state) of the Einstein-Podolsky-Rosen problem. It is argued that, on the contrary, standard quantum mechanics itself is a counterexample to Maudlin’s claim, because it is local in the appropriate sense (measurements at one place do not influence what occurs elsewhere there) when formulated using consistent principles in place of the inconsistent appeals to “measurement” found in current textbooks. This argument sheds light on the claim of Blaylock that counterfactual definiteness is an essential ingredient in derivations of Bell’s inequality.

1.
The terms “framework” and “consistent family” are used both for the sample space and the corresponding event algebra it generates. If the distinction is important one can refer to a “consistent sample space of histories.”
2.
We think of
Hs
as corresponding to internal states, say spin states, of a particle, and that its center of mass motion toward a detector is taken care of by using a unitary time development operator T(t′, t) with two arguments, rather than supposing it depends only on the time difference t′-t.
3.
Strictly speaking, Eq. (36) should be applied only in cases in which the bars are absent in the final a states in the dynamics in Eqs. (31) and (32). However, if we are only using the collapsed wave function to calculate properties of particle b this makes no difference.
4.
Naturally, one has to use a different piece of apparatus to measure different components of the spin angular momentum.
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