Shakespeare, Feynman wrote that in 1966, which was before Everett’s absolutely essentialy (and stunningly obvious in retrospect) insight spread through the physics community. Feynman’s claim in 1966 that “Nobody understands QM” thus inadvertantly illustrates one of the other great truths, which is that nobody knows what nobody knows. The accumulated pool of scientific knowledge is far too vast for any one human mind to hold more than a tiny fraction. There are six billion people in the world, and you don’t know what they know. Feynman should have stuck to saying “I don’t understand QM”, to which he could have attested of his own knowledge.
Quantum mechanics really was a very poor choice as my first example, because the application of “Think like reality” to QM is nontrivial. Before you conform your intuitions to reality, you should be very sure of what reality is.
Quantum mechanics tells us unambiguously that reality is over points in configuration space and that quarks and photons have no individual identities—if you pretend that a point in configuration space with photon 1 at A and photon 2 at B is different from a point in configuration space with photon 1 at B and photon 2 at A, you will get the wrong answer. So you have got to toss your intuitive understanding of little billiard balls, because it is definitely wrong, and start trying to wrap your understanding around configuration spaces until they seem normal, because they are definitely normal.
Once you have achieved a state where configuration spaces seem normal, many-worlds will also seem much more normal. If you insist on thinking of particles as individuals you will start to ask nonsensical questions like “Which branch am I in?” or “When does the ‘observation’ occur?” It seems to me that many-worlds is also cut-and-dried correct, but I understand that the reasons for this verdict may not be easily apparent to everyone. Questions like “How are amplitudes converted to subjective probabilities?” are not automatically dictated by the theory in the way that configuration spaces and lack of individual particle identities is dictated by the theory. So in this case, there is a legitimate question of what it is that you need to reshape your intuitions to regard as normal. If a QM interpretation seems weird, it may be that the interpretation in question is wrong and that you should not wrap your intuitions around it.
But what doesn’t change, and this is the main point I was trying to make, is that you have to pick one or the other. If a theory seems bizarre to your intuitions, then either the theory is wrong or your intuitions need reshaping. Feynman felt he didn’t understand QM, and lo and behold there was an additional insight required to make it seem normal. If Feynman thought that QM seemed bizarre and that this was okay, a state of affairs that didn’t indicate a problem with either the theory or his intuitions, then that was historically incorrect—though I don’t believe Feynman said as much in that many words.
Feynman’s claim in 1966 that “Nobody understands QM” thus inadvertently illustrates one of the other great truths, which is that nobody knows what nobody knows.
I don’t think he was actually trying to say nobody understands quantum, I’m pretty sure he was actually saying (albeit in less words): “just because you don’t understand quantum, does not mean that you are unintelligent, or that the theory is incorrect”. I believe that as you pointed “nobody knows what nobody knows”, implies that he wouldn’t make such a statement with the intentions that it should be take literally, and consequently it seems significantly more probable that the intentions of the statement were something else entirely.
I would also like to note that the statement “nobody knows what nobody knows” has only one piece of evidence attached to it, and I am curious were else you noticed it taking effect.
“Which branch am I in?” is clearly not a nonsensical question, because I actually have these memories which follow a sequence of single events—things being here and not over there. You can say it’s a pointless question, because there is another me somewhere in the other branches; but it’s clearly not meaningless, because we only experience and remember one result from each experiment.
Shakespeare, Feynman wrote that in 1966, which was before Everett’s absolutely essentialy (and stunningly obvious in retrospect) insight spread through the physics community. Feynman’s claim in 1966 that “Nobody understands QM” thus inadvertantly illustrates one of the other great truths, which is that nobody knows what nobody knows. The accumulated pool of scientific knowledge is far too vast for any one human mind to hold more than a tiny fraction. There are six billion people in the world, and you don’t know what they know. Feynman should have stuck to saying “I don’t understand QM”, to which he could have attested of his own knowledge.
Quantum mechanics really was a very poor choice as my first example, because the application of “Think like reality” to QM is nontrivial. Before you conform your intuitions to reality, you should be very sure of what reality is.
Quantum mechanics tells us unambiguously that reality is over points in configuration space and that quarks and photons have no individual identities—if you pretend that a point in configuration space with photon 1 at A and photon 2 at B is different from a point in configuration space with photon 1 at B and photon 2 at A, you will get the wrong answer. So you have got to toss your intuitive understanding of little billiard balls, because it is definitely wrong, and start trying to wrap your understanding around configuration spaces until they seem normal, because they are definitely normal.
Once you have achieved a state where configuration spaces seem normal, many-worlds will also seem much more normal. If you insist on thinking of particles as individuals you will start to ask nonsensical questions like “Which branch am I in?” or “When does the ‘observation’ occur?” It seems to me that many-worlds is also cut-and-dried correct, but I understand that the reasons for this verdict may not be easily apparent to everyone. Questions like “How are amplitudes converted to subjective probabilities?” are not automatically dictated by the theory in the way that configuration spaces and lack of individual particle identities is dictated by the theory. So in this case, there is a legitimate question of what it is that you need to reshape your intuitions to regard as normal. If a QM interpretation seems weird, it may be that the interpretation in question is wrong and that you should not wrap your intuitions around it.
But what doesn’t change, and this is the main point I was trying to make, is that you have to pick one or the other. If a theory seems bizarre to your intuitions, then either the theory is wrong or your intuitions need reshaping. Feynman felt he didn’t understand QM, and lo and behold there was an additional insight required to make it seem normal. If Feynman thought that QM seemed bizarre and that this was okay, a state of affairs that didn’t indicate a problem with either the theory or his intuitions, then that was historically incorrect—though I don’t believe Feynman said as much in that many words.
I don’t think he was actually trying to say nobody understands quantum, I’m pretty sure he was actually saying (albeit in less words): “just because you don’t understand quantum, does not mean that you are unintelligent, or that the theory is incorrect”. I believe that as you pointed “nobody knows what nobody knows”, implies that he wouldn’t make such a statement with the intentions that it should be take literally, and consequently it seems significantly more probable that the intentions of the statement were something else entirely.
I would also like to note that the statement “nobody knows what nobody knows” has only one piece of evidence attached to it, and I am curious were else you noticed it taking effect.
“Which branch am I in?” is clearly not a nonsensical question, because I actually have these memories which follow a sequence of single events—things being here and not over there. You can say it’s a pointless question, because there is another me somewhere in the other branches; but it’s clearly not meaningless, because we only experience and remember one result from each experiment.