With all due respect I think you might be a bit confused here. QM does not say there is absolutely nothing to measure beforehand, of course not. That would mean we can create reality from nothing! It says we can never predict exactly the outcome of a measurement. It’s probabilities, not certainties.
I know but QM has been the most successful theory in the history of physics so the skeptics have a lot of explaining to do. Thus far they have been unsuccessful at supplanting QM.
All it really means is we have an incomplete picture of reality. That is nothing new and will continue to be so.
You do, however, have to provide solutions to the bizarreness of QM and people have been forced to erect speculative ideas because conventional ones simply won’t work. Sometimes we have to admit that our old ideas no longer serve their purpose. The universe is much smarter than us.
Hmmm…okay true BUT in an odd kind of way the fact that we have shown entangled particles are in ‘instant’ touch with one another is a form of information in that we, as ‘observers’, possess. Whether we can go on to develop that remains to be seen. But I know what you mean and it seems to show there are ‘layers’ of reality’. Spacetime may be but one of many.
That consciousness causes the collapse of the state vector has been one possible idea that goes back decades. It seems to be the one the mystics always focus on and claim some sort of deep woo about. You seem to have been influenced by this.
However we conduct these experiments with machines and computers. We just get a printout of the results on a computer screen. You would have to suggest that the entire environment, right through the experimental apparatus, the detectors, the computer, the computer storage system, the network, the final PC the result are viewed on, are all part of this conciousness. And you have to cope with the fact that there is more than one conscious being interested in the results.
No we don’t, but you don’t get to invent new physics by saying, we don’t understand X, and we don’t understand Y, therefore X = Y.
I don’t think you get what the experiment is, or what is going on. Nor indeed do you seem to have grasped much of what has been said to you in other threads about this. A particle does not become a wave, nor does a wave become a particle. There is this popular idea that there is some sort of mystical duality, something not helped by some scientists trying to explain to the public in simple terms.
This actually makes no sense. You can’t “set” a particle to be a particle. It is what it is. And there is no “remaining so”. It behaves as it does, as described by well understood mathematics.
I thought that was you.
No it can’t, and again, these experiments do not show that this is the case. It is much more subtle. The problem is that you are imposing a classical idea about causality, state and time onto the experiment, and thus misunderstanding. In fact you are committing exactly the sin you accuse everyone else of. You need to let go of your human level ideas and intuition of time and causality and state and understand just what is being said. Conventional mysticism isn’t going to help anyone. The way QM works is not what you think. As Neils Bohr said: “Anyone who is not shocked by quantum theory has not understood it.”
No, but we have a very good, and highly verified idea of how it works. It is incomplete, and it is incomplete in exactly the area of EPR. But again, the experiment you cite is a validation of the current known science, yet you seem to continue to claim the exact opposite. We know there is a question about causality. But no experiments answer it. They just confirm the gap in knowledge.
Note, by the way, that hidden variables have not actually been ruled out by experiment. The EPR experiment means that you have to give up something that seems like it ought to be intuitively true, but there are multiple choices for what to give up, and hidden variables are only one of them. You can also, for instance, instead give up locality, and construct a perfectly good (as in, as good as any other model of quantum mechanics) nonlocal hidden variable model.
Given that these models are all equally accurate (in all cases, they all predict the same actual results), it’s largely a matter of philosophical taste which one (if any) you prefer.
IIRC if you do the double-slit experiment and put a detector near one of the slits to see which slit the particle goes through the interference pattern disappears. The other parts of the experiment do not seem to stop an interference pattern from forming but the thing that will tell you which slit the particle goes through does.
No need for a living observer.
The quantum eraser experiment also seems to have no need for a living observer yet can still change results.
It’s hard avoiding the woo with results like that.
Why does this matter?
What do you define as living?
Something that I think gets missed about these experiments in such discussions. There is nothing special about the experiments except that they try to isolate a particular part of the theory so it can be observed. But the theory predicts that every single QED interaction that happens anywhere and any time in the entire universe is bound by the same rules. All we are doing is teasing out a particular component of those rules so we can measure it.
But the rules of QED only work when every possible set of interactions is allowed for. This is a really important point. QED includes all the weird behaviour, and if you remove it from the theory, the numbers don’t match reality. You get the wrong numbers, and it predicts that all manner of mundane things are different to how they are. What this tells you is that there is nothing special about your experiment and its living observer. Every chemical reaction, every photon travelling though the universe, the vast majority of things you can conceive of are governed by these rules in a manner that affects their basic operation. The Earth has existed for billions of years without life, but the chemistry worked, and the stars have shined for billions of years, all governed by the same laws. We didn’t need an observer to make the physics work then. Why should we now?
All that machines are doing is conveying what has already been established by previous experiments because once a particular experimental situation has been performed and results observed it simply provides the same, repeatable data. The point here is we are talking about ‘information’ and information can take various forms.
Well, no, but if you have better solutions please feel free to air them here. Earlier you were criticising some of the well known interpretations of QM but simply saying ‘we don’t know’ is not very constructive.
I’m shocked that you don’t seem to have heard of the duality of light. Light can be either a wave or particle depending on how you measure it. The language you are using is a bit befuddling. A particle is both a wave and a particle at the same time but only resolves to one or the other upon measurement. You’re making it look as though we have the power to ‘create’ a particle or wave and in a way we do but you have to be careful how you use language here.
Again, language confuses. What I meant by ‘set’ is to make a measurement which combines the potential of a quantum object to ‘collapse’ to a specific state.
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Well, since words usually refer to classical ideas I have little choice, but you have to take these things as analogies. Remember, however, that whatever way we choose to represent quantum behaviour it is always going to be analogous since we can never be directly aware of what quantum objects are. Even mathematics is a set of symbols that represent analogies with with to pattern behaviour. It’s patterns of phenomena that are of interest, whether or not we can really ever know what they really are.
All you really seem to be saying here is that QM is strange and we don’t know why, which is correct. And ‘the gap in knowledge’ you mention does not mean we are able to find solutions that avoid the role of the observer. Look at the facts: an experimenter does something in an experiment that seems to violate causality. Now, how can a quantum object ‘know’ what is being done in a sophisticated scientific experiment? Obviously it can’t because it has no ‘knowledge.’ So what is the commonality here? The answer is the knowledge of the human experimenter, therefore it is the ‘information’ generated by the experiment that is acting to produce the observed result. What you are not seeing is the role of knowledge in measuring phenomena, whether examining stars, black holes, planets, etc., or the tiny world of atoms and sub-atomic particles. These things are only as real as our human representations of them are real. You are wedded to the idea of a ‘concrete’ externally existing ‘reality’ out there but this gets you nowhere in the end since we can only examine what we can examine within our own nature. Words, mathematics, images and so on are merely our way of interacting with the world and many people seem to think there is ‘stuff’ which exists quite independently of our observations and measurements which would carry on, regardless of whether we existed or not. This is a profound misunderstanding of reality and I think you may have been subject to the misguided precepts of classical paradigms.
And in fact there can’t be. As I said before, the interpretations of quantum mechanics which include nonlocal hidden variables give exactly the same results as the interpretations which do not include them. Asking which interpretation is “true” is therefore not a question for science.
Not quite a General Answer, but I have never found quantum mechanics spooky or strange. I find it logical, elegant, and beautiful. There: you can relax now; all is right with the world.
This starts to get close to a version of the strong anthropic principle. That the reason humankind (or any intelligence) exists is so that the universe can have an observer. This becomes revealed truth, ie religion. The reasoning soon becomes circular, and pointless.
You also end up with a form of solipsism. The reason you exist is so that the universe can. None of these ideas have anything going for them, and certainly don’t have any physics, or indeed logic to back them up.
And if the universe knows it exists, it is clearly conscious, and thus can observe its own existence. It thinks therefore it is. It becomes a solipsist universe. We become irrelevant.
None of this is true, to my understanding. QM has a number of interpretations. They are mathematically equivalent so they all are equally “true” or equally “false” which is saying that the numbers work or don’t work. Most everything works.
“Observation” is important only in the Copenhagen interpretation. This is sometimes given as “consciousness” and then elevated to human consciousness, but this is strenuously argued in the community. Most modern physicists define observation in non-human, non-living ways. There are bunches of other interpretations that avoid observation as a mechanism altogether.
Stuff does exist independently from us. Always has unless you believe that the universe sprang into existence the moment the first human gazed out onto the stars. That’s pure crackpottism. Reality doesn’t care about humans or lifeforms in any way.