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The theory of quantum mechanics is treated as a scientific truth, and taught that way in schools. But it seems very distanced from verifiable reality. When you look at its history, quantum mechanics looks like a bunch of stories to explain observations. And where it is not successful, more is added to the story.

Einstein said that the mathematicians took his theory of special relativity and made it into something he could not understand. Schrodinger took some fundamental ideas of Niels Bohr, added a bunch of math with integers sprinkled on and came up with wave theory. Schrödinger wrote about the probability interpretation of quantum mechanics, saying: "I don't like it, and I'm sorry I ever had anything to do with it."

If even the people who created it didn't believe in it, what is the justification for why we accept it as fact?

Chris Sunami
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John
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    Everything, including your memory of your room, your weather expectations, and your opinions about your teacher's character, are a bunch of stories to explain observations (and predict events). The difference is that Einstein's and Bohr's stories are better composed and make better predictions. Could you rephrase your question to make it less subjectively answerable? "What do you think" questions are off-topic on this SE, visit our Help Center to see what questions we answer and how to ask. – Conifold Feb 06 '18 at 04:36
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    Here is an interesting recollection by Niels Bohr on Einstein: https://www.marxists.org/reference/subject/philosophy/works/dk/bohr.htm – Gordon Feb 06 '18 at 14:15
  • Given that you're reading Einsteins biography a century after his major discoveries in physics then that's some fashion! – Mozibur Ullah Feb 06 '18 at 15:38
  • Even with your edits, this read more as a rant than a question. I did my best to edit your two version together and highlight the underlying philosophical question I perceived in it. If this does not match your intentions, feel free to revert. – Chris Sunami Feb 07 '18 at 22:44
  • I understand and respect StackExchange wanting to avoid what are essentially meaningless exchanges of opinion. But my actual theme relates to education. I think quantum mechanics should be thrown out altogether and organic chemistry should be taught first. Organic chemistry is relevant to health, energy, global warming, nutrition. “But you have to have that background in quantum mechanics first”. That is baloney. Everything in chemistry is abstract. I like StackExchange. Please be patient with me. Am I to delete this? (I put a post under [education]) – John Feb 09 '18 at 03:44
  • Well quantum mechanics is relevant to making smart phones and computers and basically all electronic devices. These are probably relevant to health, energy, and much more. – Quentin Ruyant Feb 10 '18 at 14:44

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No, quantum mechanics is NOT 'just a story'; it's the best interpretation of sub-Newtonian scale mechanics we currently have.

I'm not going to tell you that it's right; I don't know that and any scientist worth his or her salt will tell you that there are many parts of this model that we just don't understand all that well. The point is that in science, you work with the best theory you have at the time.

In this case, it's quantum mechanics.

Whether I like it or not, even though I have reservations about this theory, I have to admit that this theory conforms to observations extremely well. I can't just toss out the theory because it sounds a little counter-intuitive in places and can be inelegant; the only way I can get rid of QM is to replace it with something better.

That's perhaps the most important point here; QM was not invented as a story that all of science just latched on to. It was an attempt to explain phenomena that science could not adequately explain to the same degree possible with this theory. Just like I say that QM would have to be replaced with something better, QM in its time completely replaced Newtonian mechanics as an explanation of how the universe works. It was more complete than Newton's laws of motion in that explained variations between the laws and observation. In that sense, QM has earned its position in the scientific pantheon.

I will admit that I look forward to the day when it is replaced with a more complete, more elegant theory that doesn't have the quirks that QM does. But, until that day comes, I have to accept QM as the best explanation we have of what it purports to describe and as such is to be respected as the work of many intelligent people trying to explain a set of observations that could not be explained before its existence.

Tim B II
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Quantum theory is not a bunch of stories. It is a universal physical theory that explains everything you see around you, except for the interaction of objects with the gravitational field.

Lots of people, including physicists, don't want to accept this, and so describe quantum mechanics in terms of an ad hoc set of rules. For an example of this denial, see the answer above that describes QT as having 'quirks'. This sort of nonsense may be where you got the impression that QT is just a bunch of stories.

In reality, quantum theory has deep connections to relativity and the theory of computation and most of the features people object to in QT play a role in the explanations it gives:

http://www.daviddeutsch.org.uk/many-minds-interpretations-of-quantum-mechanics/

See Deutsch's other papers on the same site, and his books "The Fabric of Reality" and "The Beginning of Infinity".

alanf
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  • You need to replace "quantum mechanics" by "quantum theory" for your sentences to come out right. QM does not explain lasers or PET scans or even why mercury is liquid at room temperature, quantum field theory does that. QM is also non-relativistic, again unlike quantum field theory. Deutsch's work is limited to QM. – Conifold Feb 06 '18 at 21:46
  • Deutsch's argument is that the single universe worldview is incompatible with both quantum theory and experiment. If QFT featured only a single universe it would be incompatible with experimental results. But QFT doesn't suffer from that defect. – alanf Feb 07 '18 at 08:33
  • @Conifold As a Professor in the Department of Atomic and Laser Physics at Oxford, I'd say Deutsch's work is well up to speed with QFT – CriglCragl Feb 07 '18 at 11:57
  • @alanf: Deutsch presumably likes strict determinism as did Einstein; this is why he supports Everetts Many Worlds interpretation. Personally, I find the cost too high - an infinity of unobservable branching worlds; it seems to me that Occam's razor would support the simpler interpretation of there being just one world with the consequence that indeterminism in physics is real. – Mozibur Ullah Feb 07 '18 at 23:08
  • @MoziburUllah Deutsch supports Everett because it is the only existing explanation of several experiments, such as single particle interference and the EPR experiment, and because it is an implication of quantum mechanics. Your assertion that you find the cost too high is wrongheaded because there are no unrefuted competitors to the Everett theory. – alanf Feb 08 '18 at 08:26
  • @alanf: Everetts interpretation is not the only one which does that - check out relational QM, Bohmian mechanics and GRW. – Mozibur Ullah Feb 08 '18 at 11:43
  • @alanf: Everetts explanation is the only one which predicts gadzillions of worlds - where are they? – Mozibur Ullah Feb 08 '18 at 11:49
  • @MoziburUllah https://arxiv.org/abs/quant-ph/0104033 – alanf Feb 09 '18 at 08:31
  • @alanf: This doesn't answer my question about these parallel universes. If they aren't observable, by Popperian falsification it doesn't count as a scientific theory but as a flight of fancy - how can you falsify something that isn't observable? – Mozibur Ullah Feb 09 '18 at 12:18
  • @MoziburUllah By that criterion dinosaurs don't exist. You can't observe dinosaurs only fossils. The mistake you made is that you have to understand observations in terms of explanations - accounts of what is happening in reality to bring about the events you observe. Dinosaur exist and their existence can be criticised through experiment by saying 'if X is true then the experiment should have outcome Y'. If Y doesn't happen X is wrong. The same is true of the Everett theory https://arxiv.org/abs/1508.02048. – alanf Feb 10 '18 at 11:49
  • @alanf: Well, dinosaurs don't exist. They have existed. When Dirac predicted the unobserved positron it was found ten years later. Parallel universes even in principle are not observable - not now, not in the future, not ever. Deutsch can argue all he likes about an infinite number of unobservable universes and what constitutes a scientific explanation but the simpler explanation by far is simply that classical determinism doesn't hold. – Mozibur Ullah Feb 10 '18 at 20:21
  • @alanf: I think Dirac was much more perceptive in this regard than Deutsch. Dirac quite explicitly said that 'Nature makes choices' and obviously this means Nature is not strictly deterministic as in that picture no choices are made. – Mozibur Ullah Feb 10 '18 at 20:36
  • @MoziburUllah If you try to explain single particle interference, EPR experiments etc without the multiverse you will fail. Furthermore, any non-multiverse explanation violates constraints from other theories such as Lorentz invariance. In addition the existence of the multiverse is an implication of quantum mechanics. So your view requires throwing out quantum mechanics and special and general relativity and starting afresh with none of the physical principles of those theories. Throwing out QM also has bad effects on the theory of computation. Doesn't sound simple. – alanf Feb 11 '18 at 21:27
  • @alanf: I don't know why you're involving Lorentz invariance in QM. QM has nothing to do with relativity, QM+relativity=QFT. What I find astonishing is that you're referencing Arxiv papers with mathematics and physics which I suspect that you're not competent to understand. Do you understand them? I don't and I have advanced degrees in both mathematics and physics. I rather suspect that you don't really understand much of either and that renders your assertions even more suspect. – Mozibur Ullah Feb 12 '18 at 02:45
  • @MoziburUllah Yes I know about QFT. Since you seem to be confused on this point I will clarify: I was using QM to refer to quantum theory more widely. The fact that interactions with quantum systems in general gives rise to multipkle versions of the same system doesn't change in QFT https://arxiv.org/abs/quant-ph/0204024. Any single universe theory that matches the predictions of QM or QFT or whatever term you want to use is non-Lorentz-invariant, see "Quantum mechanics, local realistic theories, and Lorentz-invariant realistic theories" by Lucien Hardy. – alanf Feb 12 '18 at 08:38
  • @MoziburUllah As for understanding papers, you do actually have to read papers and think about them and preferably try to follow the maths to understand the logic of the underlying explanation. the maths in the Deutsch papers is in general not very difficult. If you understand Pauli matrices, tensor products and projectors, you won't have much trouble if you make a serious attempt. – alanf Feb 12 '18 at 08:39
  • @alanf: I'm afraid you're the one confused upon this point. You've already been told once that QM does not take into account relativity and yet you've persisted in making the same mistake. If you've made a mistake on this basic point it doesn't lend much confidence on your pontifications on physics. How far have you formally studied physics and mathematics? – Mozibur Ullah Feb 12 '18 at 13:23
  • @alanf@ since 'you understand QFT' perhaps you can explain what are principal bundles and what their importance are in QFT? Perhaps you can also explain why Pauli matrices are often exponeniated - why do we do this and what does it mean? – Mozibur Ullah Feb 12 '18 at 13:34
  • @MoziburUllah You have a terminological nitpick about my use of the term quantum mechanics you're using to avoid discussing substantive issues. A principal fiber bundle is a collection (B,E,P,G) of a base manifold B, a total space E, a projection P from E onto B, and a continuous group G that maps the fiber at each point of B back to itself. Gauge fields can be represented by connections on principal bundles. Pauli matrices are exponentiated because any element of SU(2) can be represented by e^ia(n.sigma) where a is a real number, n is a unit vector and sigma is a vector of Pauli matrices. – alanf Feb 12 '18 at 21:03
  • @MoziburUllah If at some point you're interested in learning you can read the references I provided, or not. – alanf Feb 12 '18 at 21:04
  • @alanf: I wouldn't call that a terminological slip, more like a Freudian one. Once is fair enough - everyone makes mistakes - twice seems strange. That's not a definition of a principal bundle but a bundle with the action of a group. There's a couple of things missing which is essential. – Mozibur Ullah Feb 12 '18 at 21:05
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Well, until we undoubtedly unlock all the secrets of the universe, everything is "just a story" but sometimes that is okay, especially if the story is a useful one for us. Quantum Mechanics has wonderful applications and the story part of it help us think of more bizarre and wonderful implications.

ThunderVault
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Einstein could have been a fashionable story-teller, but given that you're reading Einsteins biography a century after his work then thats some fashion!

Although Einstein did complain about the mathematical formalism that Minkowski adopted for the theory of relativity it turned out to be essential to his work on General Relativity. Einstein wasn't great mathematician, he struggled with the tensor formalism. What he's known for is his great physical insight.

The main disagreement that Einstein has with QM was the loss of strict determinism which is implicit in Newtonian Mechanics and is still implicit in General Relativity. One of the lessons that QM teaches us is that strict determinism isn't neccessary to physics and maybe inimical to it.

In fact it is possible to have a strictly deterministic QM; this is Everetts Many Worlds interpretation where he dispenses with the collapse of the wave function; but this is with the disagreeable cost of an infinity of additional branching worlds. One might say here that the cost here is too great.

Mozibur Ullah
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