2 basic questions from a non-physicist (sigh!). Is decoherence essentially a measurement? And if so is the system of quantum particles set into the classical world forever? Or is there a mechanism by which it will evolve again into a superimposed state? Secondly, if the particle (as in the 2 slit experiment) is essentially everywhere possible at a given time, then what sense can be given to assessing the probability that the particle can be found in a specific place?