Quantum wave function?

[crystalmage]

I know that an observer can cause the quantum wave function to collapse. Can the quantum wave function collapse in the absence of an observer?

[seventil]

I know that an observer can cause the quantum wave function to collapse. Can the quantum wave function collapse in the absence of an observer?

If you're talking of wave function collapse, there is more to it.

Observation and measurement can "cause" this, due to the "quantum leap" (great show) that occurs when you do one or the other.

It also occurs while not observed or measured, according to Schrodinger's equation.

More on this: http://en.wikipedia.org/wiki/Wavefunction_collapse

[QED]

The role of the Observer is different in different interpretations of QM. The Copenhagen interpretation is the one that led Schrödinger to his thought experiment about a cat -- who's fate was absurdly suspended until an observer checked-up on it.

Other interpretations are free of such nonsensical roles for conscious observers -- yet come with their own seemingly peculiar baggage. John Cramer's Transactional interpretation dispenses with the observer at the cost of living with signals that apparently go backwards in time. However the nature of things (e.g. photons) at the Quantum level is such that travelling at the speed of light, signals take no time at all to complete any journey -- as for light-speed signals, every point in the Universe is the same. It therefore makes no difference if the signals are travelling backwards or forwards as they take zero time in their own frame of reference, and "plus zero" is the same as "minus zero".

[seventil]

The role of the Observer is different in different interpretations of QM. The Copenhagen interpretation is the one that led Schrödinger to his thought experiment about a cat -- who's fate was absurdly suspended until an observer checked-up on it.

Other interpretations are free of such nonsensical roles for conscious observers -- yet come with their own seemingly peculiar baggage. John Cramer's Transactional interpretation dispenses with the observer at the cost of living with signals that apparently go backwards in time. However the nature of things (e.g. photons) at the Quantum level is such that travelling at the speed of light, signals take no time at all to complete any journey -- as for light-speed signals, every point in the Universe is the same. It therefore makes no difference if the signals are travelling backwards or forwards as they take zero time in their own frame of reference, and "plus zero" is the same as "minus zero".

I love quantum mechanics. Every time I need to make my head feel like it should explode, I just go read up on it. The great thing is, the deeper you delve, the weirder it gets. However, as I have no practical use for this knowledge other than impressing people when I drink and a tidbit here on the forums, I find I don't retain everything very well.

Apparently the Transactional Interpretation jives with the Afshar Experiment and Copenhagen's does not. However, the Afshar experiment isn't well received among scientists, it seems.

[crystalmage]

The closer we get to the truth the farther we get from what we used to percieve to be true.

[QED]

The closer we get to the truth the farther we get from what we used to percieve to be true.

Perhaps it's more appropriate to say that we continually manage to surprise ourselves at just how wrong our firmly-held preconceptions can be. This, I think, reflects something of the nature of the human mind in that it shows a requirement for us to form simple models of a much more complicated world and stick with them for as long as we can. There's no problem explaining this kind of behaviour from an evolutionary perspective so it shouldn't be a mystery.

Out of interest -- does the demotion of the conscious observer from "reality creator" to "humble spectator" give you any cause for doubt?

[Openmind]

Perhaps it's more appropriate to say that we continually manage to surprise ourselves at just how wrong our firmly-held preconceptions can be.

a la religion.

[crystalmage]

Out of interest -- does the demotion of the conscious observer from "reality creator" to "humble spectator" give you any cause for doubt?

I didn't quite get this.
In my believe system I'm creating every thing that I see and experience in my mind or something.
It's possible that some higher force created me. Or the illusion that I now create. But I do believe that i'm the reality creator. I'm not just passively viewing the movie that god created for me. Wouldn't that be something. God creates the life that you view then punishes you if its a bad movie.

[seventil]

Out of interest -- does the demotion of the conscious observer from "reality creator" to "humble spectator" give you any cause for doubt?

If I understand your question correctly, you imply that our normal self is a "reality creator" but when we become the observer in quantum mechanics we become a humble spectator?

I've always believed as humanity as humble spectators. Perhaps (and likely) I misunderstood your question.

[QED]

Out of interest -- does the demotion of the conscious observer from "reality creator" to "humble spectator" give you any cause for doubt?

I didn't quite get this.
In my believe system I'm creating every thing that I see and experience in my mind or something.

You started this topic asking if anything else other than an observer could collapse the QM wave function. The introduction of this new apparent role for the conscious observer by way of the Copenhagen interpretation is one that divided the early exponents of Quantum Theory and remains as a mystical interpretation to this day. I was curious to know whether or not the alternative interpretations we had presented here had eliminated the mysticism.

It's possible that some higher force created me. Or the illusion that I now create. But I do believe that i'm the reality creator. I'm not just passively viewing the movie that god created for me. Wouldn't that be something. God creates the life that you view then punishes you if its a bad movie.

It has been suggested that time is a higher dimensional aspect of a (minimum of) four-dimensional object of which we can only experience three of the dimensions simultaneously. This makes the past, present and future of space an integral whole - as a solid book is to an individual page. The apparent impossibility of saying whether or not the future is predetermined keeps me from forming any real beliefs about this kind of thing, but at least the theists have this much right: if the future is determined, then God truly is working in a mysterious way.