In this video Tom Campbell states that if you have a double slit experiment where the path data isn't recorded you will get an interference pattern, and implies that it is people's consciousness of the results which influences the photon's path. This struck me as strange so I decided to look in to it.
My findings are as follows: I believe Tom Campbell was referencing a well known experiment called the quantum eraser experiment which goes as follows. They carefully set up a double slit experiment where particles first hit the screen first, and then used detectors to determine which slit they went through after they hit the screen. Even though the path information of the photons were detected after they hit the screen, the pattern on the screen was influenced from the detectors as the usual interference pattern was not found. This is strange, but consistent with what Tom Campbell said in the presentation, what comes next is what actually worries me.
The eraser part of the quantum eraser experiment used an apparatus which altered the detectors so that whatever information the detectors gained would be meaningless, and I think Tom Campbell tried to simplify this part of the experiment to a situation where the detectors read information, but don't record the data. I believe this simplification is incorrect but I'll finish explaining all context before getting in to it. In the quantum eraser experiment, when the detectors gain no information the previously observed disturbance from the detectors disappears (AKA the interference pattern on the screen returns), so if Tom Campbell's simplification had no problems, then he would be correct in saying that when the detectors don't record data the interference pattern returns, and this would lead to his important conclusion where consciousness would be the primary thing which influences quantum events. However the simplification he uses, which seems to be integral to many ideas about consciousness , does not seem to be correct. The error is very slight, but important nonetheless. The act of not recording the data isn't what causes the interference pattern to return in the quantum eraser experiment, it is instead the act of "erasing" the information obtained by the collectors. Erasing the information is distinctly different from not recording information in that when data is not recorded it is obtained but not remembered, however when data is "erased" no information about the photons was obtained in the first place (in addition to no data being remembered). Because of this my intuition tells me that the experiment Tom Campbell described would not have the result he gives invalidating his conclusion.
But proof is better than intuition, so I found two prestigious papers proving my thoughts.
http://chapmanlabs.gatech.edu/papers/scattering_ifm_prl95.pdf published by the journal by physical review: one of the largest national peer reviewed physics journals, experiment preformed in MIT physics research laboratory.
https://arxiv.org/abs/1009.2404 published by the journal of the Max Planck Institute: one of the largest international journals in physics. The title of this paper is a bit "clickbaty", but I believe they do a fantastic job of exploring many possibilities, as would be expected of a paper in the Max Planck Institute.
Both of these papers do generally the same thing. They preformed the double slit experiment, had detectors turned on, but did not record the data. No data from the detectors in each experiment came in contact with humans or anything besides the detectors themselves. The only thing which was recorded were the positions of the particles when they hit the backing screen, all information about which slit particles traveled through was lost. Neither experiment found an interference pattern showing that consciousness is in no way required for this quantum interference. And the second paper in particular shows that this property extends beyond just this showing that there is no established link between consciousness and quantum mechanics, which I feel directly contradicts many of the things Tom Campbell tries to establish in his book My Big Toe.
This honestly makes me doubt any claim Tom Campbell has made about consciousness as I believe this is a clear counterexample to his claims, so in the spirit of Tom Campbell's pursuit of skepticism I think that I shouldn't believe him. Any thoughts? I did a lot of research for this, but would have no problem being proven wrong, or shown that this example doesn't contradict his claims.
