From Eric Kvaalen, Les Essarts-le-Roi, France
You say that particles' states “can be entangled – such that altering one affects the other much faster than light can travel between the two” (11 February, p 7). But you do not affect the other. Measuring some property of one determines the outcome of a measurement on the other.
In an experiment like the one described, you cannot say the measurement at A affected the photon at B: it would be just as valid to say the opposite.
