Thought experiment: Observation via Recording

[Vulpes vulpes]

I'm just a physics dilettante, so if I make no sense, please forgive me.

Imagine any setup that creates macroscopic effects from quantum events. The setup is isolated from observation. Schrödinger's cat would work, but I happen to like cats so we'll just say a light either goes on or doesn't.

Now, inside the box, along with setup, is a camcorder, which will videotape whether the light goes on or doesn't. The experiment is run and the camcorder records the experiment. Without observing the light, the tape is removed and copied. The copies are moved apart a significant distance. Then, at the same time, each tape is watched by a person.

If observation by a consciousness is required to collapse the wavefunction, then, if they show the same thing like we would expect, how did the information (about whether or not the light went on) travel instantaneously between the two copies when the copies are observed simultaneously at a distance?

 

[jtbell]

If observation by a consciousness is required to collapse the wavefunction

No, it's not.

 

[Vulpes vulpes]

Yes, that's what I'm trying to say. Not requiring consciousness avoids the problem.

I was under the impression that the wavefunction collapses upon observation in some interpretations. Am I mistaken?

 

[G01]

Measurement in quantum mechanics does not require the presence of a conscious being.

The "measurement" occurs when the quantum system under consideration interacts with the environment around it, undergoing a process known as decoherence, through which quantum effects are washed out leaving an effectively classical state as a result.

The point is that consciousness has nothing to do with measurement. The measurement occurred when the "quantum light bulb" interacted with the video camera (the video camera absorbed photons from the bulb). This caused decoherence and the video will show the light bulb in some classical state. Both copies of the video will show the same result.

There is a difference between a quantum superposition of states, and uncertainty about which classical state a system may be in. In this case, with the two unwatched videos, we have the latter.

 

[Vulpes vulpes]

So, what you're saying is, my thought experiment just illustrates what is already commonly believed.

Ah well. Kant said that genius is the ability to independently arrive at and understand concepts that would normally have to be taught by another person, so I'll take solace in that.

 

[jtbell]

So, what you're saying is, my thought experiment just illustrates what is already commonly believed.

Yes, you find the stuff about "consciousness collapsing the wave function" only in some pop-sci books and in "fringe science" sources.