Observer (quantum physics)

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 have to necessarily present or solve any problems over and above the issue of measurement in quantum mechanics. The quantum mechanical observer is also intimately tied to the issue of observer effect.

A number of new-age religious or philosophical interpretations of quantum mechanics, notably "consciousness causes collapse", give the observer a special role, or place constraints on who or what can be an observer. However, this is not founded in quantum physics.