God post, very well explained.
I've seen the double slit expereriment in a class before and the part about the detectors determining which slit the photon went through and the pattern not happening(wave colapse) was not mentioned. I find it hard to believe that the interference pattern goes away when you observe what slit the photon goes through unless the detectors are affecting the photons and the detectors are the cause for the pattern to disappear. I don't buy it that the waves 'know' when they are being observed and then collapse into particles.
Next I place a detector at each slit to determine which slit the photon passes through on its way to the film so I can understand what is happening. But when the experiment is arranged in this way, the interference pattern disappears -- for reasons still not well understood, when the photon is not being observed, it acts as a wave but when detectors are placed at each slit to observe the photon, the wave function collapses and it acts only as a single particle! Thus, how the particle behaves seems to depend on whether that particle is being observed or not. How do particles know when they are, or are not being observed?
This seems to suggest that the detectors are affecting the photons. Perhaps when the photon hits the detector it messes up the interference pattern it would have made.
Also, I don't see how you go from this:
if photons are to be particles rather than waves as they sometimes are, it requires a conscious observer to collapse the wave-function--to make the reality of our universe, real indeed.
to this:
It seems that for our universe to exist as it does at all, the universe must be observed by a supreme, conscious observer.
It seems like a pretty big jump to me. In order for waves to act as particles we have to be observing them, so in order for the universe to exist god has to be oberving it.
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