Why is the fundamental theoretical framework of contemporary physics a probability calculus, and why are the events to which this assigns probabilities measurement outcomes? It seems to me that all previous attempts to arrive at satisfactory answers have foundered on two assumptions that are at odds with the theory’s ontological implications. The first is the … Continue reading 2 Time symmetric quantum mechanics

Suppose that the subspaces A and B represent two possible outcomes of the same measurement. What measurement outcome is represented by the span AUB of A and B? (You will remember that the span of A and B is the smallest subspace containing both A and B.) The following observations are relevant here. Let p(A) … Continue reading 9 Beyond “either-or”

As Greenberger, Horne, and Zeilinger have shown,[1] quantum mechanics allows us to prepare three particles A, B, C and to subject each to either of two measurements X, Y in such a way that the outcome of each measurement is either +1 or −1, the product of the three outcomes is −1 if each particle … Continue reading 7 The GHZ experiment