Natural Science Forum / Physics / Particle Physics / August 2004

Your statement about Quantum theory is not universally valid. It is
only valid of a small set of Quantum theory interpretations and those
that promote those views have rarely, if ever, claimed a sentient being
on a single planet was required. A magnet does a great job of collapsing
the wave function of an electron ... even when no one is looking.

Actually what you are talking is just philosophical one.

1) If it is not observed by human, but by a cat or dog, it is impossible to
know what has happened. ONLY if your cat can speak any human language and
with scientific training (plus ability to do scientific research).

2) Before or after your observation, you don't know what is going on inside
the target under research. You know only the phenomena when you are
observing it. How can you know that what is the state before or after your
observation.

3) But in practical sense, you must induce something into the system in
order to observe something from an extremely small systems of bodies. So you
will affect its states. For example, you send a gamma ray to see its
behavior.

Collapse of the wave function is still a controversial issue.  It is
more or less an ad hoc addition to the theory and many people still
find it somewhat ugly.  Frankly, there are a lot of physical processes
occuring on the quantum level all the time, that no one ever sees, yet
no one really doubts that they are actually occuring.  So I think that
the whole concept of the importance of the observer in quantum
mechanics is a bunch of nonsense.  And the fact that it keeps making
its way into popular scientific literature only makes it worse.