What we are talking about here is what happens when a water molecule bumps into one of a pair of entangled particles: its subsequent motion will be affected by the state of that particle, so that if you were to study the water molecule’s subsequent motion you could deduce some of the properties of the particle it had bumped into. So, in this sense, the water molecule has carried out a “measurement” because its motion provides a record of the state of the entangled pair, whether or not anyone is there to examine it. This kind of accidental measurement is usually sufficient to destroy entangled
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