In quantum mechanics, "observation" is synonymous with quantum measurement and "observer" with a measurement apparatus and observable with what can be measured. Thus the quantum mechanical observer does not necessarily present or solve any problems over and above the (admittedly difficult) issue of measurement in quantum mechanics. The quantum mechanical observer is also intimately tied to the issue of observer effect.
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Everyone is entitled to their own facts. That's not an opinion. At least, according to a new quantum mechanics study. What ...