(2017-10-02, 08:23 AM)Chris Wrote: [ -> ]Well, I've been slowly reading through Radin's double-slit papers, and haven't quite got to the end yet. But I am a bit clearer about things now. After a quick look at the revised version, a lot has been done to address the previous issues, and it seems reasonable as far as the V1 variable (which produces a Z value of 3.43), but I'm still not convinced about the procedure by which the V2 variable is added (or subtracted), to produce Z=4.68.
(V1 is related to the ratio of the amounts of light coming through the two slits, whereas V2 is related to a phase difference between them.)
There is still the puzzling feature that the V1 effect is in the opposite direction from the one expected.
Can you explain why Guerrer's replication is now 4ish sigma and no longer 6 for me Chris?
Just to explain very briefly what the concerns were -
In the previous experiments, Radin et al. used a number of different measures to characterise the effect of attention/concentration on the interference pattern. They were always partly based on the magnitude of the oscillations in the wavelike pattern of interference fringes. In some studies there was also a contribution from the phase of the oscillations (which relates to shifts in the location of the fringes).
Gabriel Guerrer's analysis is based entirely on the phase. The interference pattern is Fourier transformed, to break it down into a combination of a lot of sine waves with different wavelengths, each with a magnitude and a phase. Guerrer defines several variables called V, by adding up the change in the phase between concentration and relax conditions, over certain ranges of wavelengths. (In the original version the analysis used three ranges of wavelengths, and three resulting variables - V1, V2 and V3. In the revised version there are only two - V1 and V2.)
One problem with the original version was that the ranges of wavelengths were determined by an optimisation procedure. The ranges were chosen so as to maximise the difference between the concentration and relax conditions. But that really amounts to trying multiple hypotheses and picking the one that gives the most significant result, so it will tend to inflate the significance. In the revised version, the ranges are determined from the data for the first of the five experiments, and those data are excluded from further analysis, which solves that problem.
But another problem relates to how V1 and V2 should be combined together to form a single measure of the differences between the pattern in the concentration and relax conditions. The snag is that there are five different experiments, and the feedback given to the participants is differently defined in each. Sometimes the feedback tells the participants they're doing well if the amount of light going through the left-hand slit increases, but sometimes it encourages them to boost the amount going through the right-hand slit. That will tend to have opposite effects on the phase shifts. So, for example, V1 can be expected to be positive in some experiments, but negative in others.
Now, in the paper, there is a table in which the expected sign of V1 is worked out for each of the five experiments from the form of the feedback, using a simple model. So on that basis there is rational way of working out how to combine together the values of V1 for the different experiments. That seems reasonable (assuming those predicted signs of V1 have been worked out correctly). But then V2 is added in, and it still seems to me that there's a problem with this step, because there isn't a rational way of choosing the sign of V2.
But as I say, I have only had a very quick look at the paper so far, so I may well be missing something.
(2017-10-02, 11:32 AM)Roberta Wrote: [ -> ]Can you explain why Guerrer's replication is now 4ish sigma and no longer 6 for me Chris?
Yes - continuing from my last post, I can see three reasons why the Z value will be smaller. First, the contribution from the variable V3 (which was also problematical) has been removed. Second, for the remaining variables V1 and V2, their defining ranges are no longer being optimised in the way they were originally, and that also reduces the significance of the results. Third, the data for Experiment 1, which are now being used to define those ranges, are excluded from further analysis, so the overall result is based on a smaller amount of data, which also tends to reduce the significance.
(2017-10-02, 08:23 AM)Chris Wrote: [ -> ](V1 is related to the ratio of the amounts of light coming through the two slits, whereas V2 is related to a phase difference between them.)
Sorry, if anyone is trying to make sense of my comments, I realise that probably looks very confusing.
What I mean is that - why V1 and V2 are both made up from changes in phase of the components of the interference pattern - V1 comes from a range of wavelengths for which the changes in phase are mainly supposed to reflect a change in the ratio of amounts of light coming through the two slits, while V2 comes from a different range of wavelengths, and is supposed to reflect a phase difference between the light coming through the two slits.
(2017-10-02, 12:02 PM)Chris Wrote: [ -> ]But another problem relates to how V1 and V2 should be combined together to form a single measure of the differences between the pattern in the concentration and relax conditions. The snag is that there are five different experiments, and the feedback given to the participants is differently defined in each. Sometimes the feedback tells the participants they're doing well if the amount of light going through the left-hand slit increases, but sometimes it encourages them to boost the amount going through the right-hand slit. That will tend to have opposite effects on the phase shifts. So, for example, V1 can be expected to be positive in some experiments, but negative in others.
Now, in the paper, there is a table in which the expected sign of V1 is worked out for each of the five experiments from the form of the feedback, using a simple model. So on that basis there is rational way of working out how to combine together the values of V1 for the different experiments. That seems reasonable (assuming those predicted signs of V1 have been worked out correctly). But then V2 is added in, and it still seems to me that there's a problem with this step, because there isn't a rational way of choosing the sign of V2.
But as I say, I have only had a very quick look at the paper so far, so I may well be missing something.
I've finally got around to reading the revised version properly, and I was indeed missing something. The intention now is to treat all the experiments to date as exploratory, and to do a further two series of pre-registered formal experiments with the same feedback as in Experiments 4 and 5 presented in the preprint (which gave the most significant results for the V1 and V2 variables separately). In the formal experiments, the expected signs of the V1 and V2 variables will be based on the signs of these two variables observed in Experiments 4 and 5. This will get around the problems of V1 having the opposite sign to that expected on theoretical grounds, and of there being no theoretical way to determine the expected sign of V2 - and will allow all the results in the formal experiments to be analysed with reference to a pre-determined statistical hypothesis.
But of course, the down-side of treating all the experiments to date as exploratory, is that we'll have to disregard the statistical results based on them, and wait and see whether the formal experiments confirm the new hypothesis.
(2017-10-28, 12:53 PM)Chris Wrote: [ -> ]I've finally got around to reading the revised version properly, and I was indeed missing something. The intention now is to treat all the experiments to date as exploratory, and to do a further two series of pre-registered formal experiments with the same feedback as in Experiments 4 and 5 presented in the preprint (which gave the most significant results for the V1 and V2 variables separately). In the formal experiments, the expected signs of the V1 and V2 variables will be based on the signs of these two variables observed in Experiments 4 and 5. This will get around the problems of V1 having the opposite sign to that expected on theoretical grounds, and of there being no theoretical way to determine the expected sign of V2 - and will allow all the results in the formal experiments to be analysed with reference to a pre-determined statistical hypothesis.
But of course, the down-side of treating all the experiments to date as exploratory, is that we'll have to disregard the statistical results based on them, and wait and see whether the formal experiments confirm the new hypothesis.
Another down-side is that even if there is a genuine effect made up of the two components included in the theoretical model, it's not entirely safe to assume that the results of Experiments 4 and 5 will give the signs of the components correctly. While the effects appear to be pretty strong in Experiment 5 (Z=-3.15 for the V1 variable and Z=-2.87 for the V2 variable), they appear much weaker in Experiment 4 (Z=1.85 for V1 and Z=-1.32 for V2). A Z value of -1.32 is not conclusive that the expected value is less than 0.
I'm still trying to figure out what may (or may not) be going on in these experiments, and in the previous ones by Dean Radin and others.
Could any Quantum Mechanics enthusiasts give me some help with the underlying concept? If I understand correctly, the motivation for looking at a double-slit system, from a psi point of view, is that the interference pattern is the result of wave-like behaviour by the photons, and that if a measurement is made of which slit the photons are passing through, the fringes disappear. So if the photons could be "psychically measured", that should tend to weaken the pattern. (Note, however, that the participants in Guerrer's experiments were told only to try to enhance the feedback they were receiving, and those in Radin's were told various things, but weren't usually told explicitly to try to measure where the photons were going.)
[Image: doubleslit.jpg]
Radin used various analysis techniques, but the common feature was an attempt to quantify the intensity of the double-slit interference pattern (at the bottom in the figure), relative to that of the single-slit diffraction pattern (at the top). Again, Guerrer uses a different analysis technique - he assumes that the effect is to change the amounts of light which go through the two slits, and to introduce a phase-difference between the light going through the two slits.
What I don't understand is why a psychical measurement of the photons - if that were the mechanism - shouldn't also affect the single-slit diffraction pattern,
as well as the double-slit interference pattern. The diffraction pattern is also a result of wave-like behaviour by the photons, and if I understand correctly, it should also be disrupted by measurement of the photons as they pass through the slit - if that measurement yields extra information about position and momentum, in addition to indicating which slit the photon is passing through. And I can't imagine any reason why a psychical measurement would be confined to "which way" information.
But maybe I am misunderstanding something.
(2017-11-01, 04:50 PM)Chris Wrote: [ -> ]I'm still trying to figure out what may (or may not) be going on in these experiments, and in the previous ones by Dean Radin and others.
Could any Quantum Mechanics enthusiasts give me some help with the underlying concept? If I understand correctly, the motivation for looking at a double-slit system, from a psi point of view, is that the interference pattern is the result of wave-like behaviour by the photons, and that if a measurement is made of which slit the photons are passing through, the fringes disappear. So if the photons could be "psychically measured", that should tend to weaken the pattern. (Note, however, that the participants in Guerrer's experiments were told only to try to enhance the feedback they were receiving, and those in Radin's were told various things, but weren't usually told explicitly to try to measure where the photons were going.)
[Image: doubleslit.jpg]
Radin used various analysis techniques, but the common feature was an attempt to quantify the intensity of the double-slit interference pattern (at the bottom in the figure), relative to that of the single-slit diffraction pattern (at the top). Again, Guerrer uses a different analysis technique - he assumes that the effect is to change the amounts of light which go through the two slits, and to introduce a phase-difference between the light going through the two slits.
What I don't understand is why a psychical measurement of the photons - if that were the mechanism - shouldn't also affect the single-slit diffraction pattern, as well as the double-slit interference pattern. The diffraction pattern is also a result of wave-like behaviour by the photons, and if I understand correctly, it should also be disrupted by measurement of the photons as they pass through the slit - if that measurement yields extra information about position and momentum, in addition to indicating which slit the photon is passing through. And I can't imagine any reason why a psychical measurement would be confined to "which way" information.
But maybe I am misunderstanding something.
You've not. Remember the slit experiment is not just a demonstration of pk it's also a demonstration of conforming physical reality to ones will. In short ones intention is expected to change what previous double slit experiments always show.
(2017-11-01, 04:50 PM)Chris Wrote: [ -> ]I'm still trying to figure out what may (or may not) be going on in these experiments, and in the previous ones by Dean Radin and others.
Could any Quantum Mechanics enthusiasts give me some help with the underlying concept? If I understand correctly, the motivation for looking at a double-slit system, from a psi point of view, is that the interference pattern is the result of wave-like behaviour by the photons, and that if a measurement is made of which slit the photons are passing through, the fringes disappear. So if the photons could be "psychically measured", that should tend to weaken the pattern. (Note, however, that the participants in Guerrer's experiments were told only to try to enhance the feedback they were receiving, and those in Radin's were told various things, but weren't usually told explicitly to try to measure where the photons were going.)
[Image: doubleslit.jpg]
Radin used various analysis techniques, but the common feature was an attempt to quantify the intensity of the double-slit interference pattern (at the bottom in the figure), relative to that of the single-slit diffraction pattern (at the top). Again, Guerrer uses a different analysis technique - he assumes that the effect is to change the amounts of light which go through the two slits, and to introduce a phase-difference between the light going through the two slits.
What I don't understand is why a psychical measurement of the photons - if that were the mechanism - shouldn't also affect the single-slit diffraction pattern, as well as the double-slit interference pattern. The diffraction pattern is also a result of wave-like behaviour by the photons, and if I understand correctly, it should also be disrupted by measurement of the photons as they pass through the slit - if that measurement yields extra information about position and momentum, in addition to indicating which slit the photon is passing through. And I can't imagine any reason why a psychical measurement would be confined to "which way" information.
But maybe I am misunderstanding something.
Have you reached out to Radin? This isn’t a new experiment. He references various papers decades ago that were testing similar concepts.
(2017-11-02, 02:26 AM)Iyace Wrote: [ -> ]Have you reached out to Radin? This isn’t a new experiment. He references various papers decades ago that were testing similar concepts.
No, I haven't contacted Radin. I just wondered whether anyone here had any thoughts on it.
I think the only pre-Radin double-slit psi experiments were those published by Ibison and Jeffers in 1998:
http://psiencequest.net/forums/thread-27...ml#pid6581
They just looked at the heights of the central peak and the adjacent troughs of the interference pattern. They gave very little discussion of how they expected psychical observation to affect those heights, though evidently they expected the fringe pattern to weaken, so that the peak height would decrease and the trough heights would increase. But it seems to me that if diffraction as well as interference were affected, that might tend to increase the peak height.