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As a physicist who spent large parts of his university years studying quantum mechanics, I actually agree with the magazine’s lambasting of Adam Becker’s book on quantum physics. The Copenhagen interpretation works just fine & the problems Becker seems to find with it do indeed seem to be due to a lack of understanding of the theory.
Since Einstein (who did understand it) was also unhappy about quantum mechanics Becker might be forgiven, but it does weaken his points.
Which are pretty strong to begin with. Giving creationists and climate deniers space in a scientific journal “just becase” is a terrible idea.
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That’s mad, I had no difficulty believing, in fact immediately assumed, that PCI Audio Card was a real magazine. After all…
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Copenhagen and other collapse theories may “work” just fine, but there are valid criticisms of their ontic basis. If you don’t care in the slightest about the ontic implications of your theory, then “shut up and calculate” works fine, but the history of physics shows that we should care…hence the popularity of relative state interpretations such as Everett.
That’s a long debate, which basically played out between Bohr and Einstein in the 1930’s.
The ontological limitations of quantum mechanics are to do with our ability to define the physical quantites in question. In that regard, I recommend Bohr’s response to the EPR paper: https://journals.aps.org/pr/pdf/10.1103/PhysRev.48.696
The fundamental thing is this, which Einstein was also very clear about: Physics is not, in the deepest philosphical sense, about “reality”. It’s about building models that can account for observations. Einstein was, as I said, completely on board with that and considered time and space to be free inventions of the human mind.
Only he wanted models (theories) to conform to a norm that they posit an external world existing independently of any observer or measuring apparatus. The Copenhagen interpretation is the necessary consequence of the fact that with subatomic physics this is no longer possible, as amply showed by Aspect’s experiments and the ultimate failure of Bohm-like models.
This is compatible with “shut up and calculate”, but the Copenhagen interpretation can in no way be reduced to that.
There’s nothing necessary about Copenhagen; it’s one interpretation, of which decoherence theories are another. Copenhagen posits an a-causal collapse; decoherence theories / Everett are unitary and deterministic but require unobservable other branches of the UWF. While observationally indistinguishable, they have very different ontic implications wrt realism. Realists would disagree that Physics is not about reality.
Thing is, though: If Everett-like theories “require unobservable other branches of the UWF” then they introduce a metaphysical entity for no good physical reason at all, solely in order to salvage a causal interpretation which is likely not salvageable in this domain anyway.
At least that’s what Bohr thought when he diagnosed the situation as such: “Indeed the finite interaction between object and measuring agencies conditioned by the very existence of the quantum of action entails — because of the impossibility of controlling the reaction of the object on the measuring instru- ments if these are to serve their purpose — the necessity of a final renunciation of the classical ideal of causality and a radical revision of our attitude towards the problem of physical reality.”
The thing is this: Causality is, as already pointed out by David Hume, a concept invented and used by the human mind in order to make predictions, not a universal property of an independent reality. As such, there will be limits to its applicability, and the standard interpretation is that quantum physics has reached that limit.
As long as it introduces no new predictions that differ from standard quantum mechanics, Everett- and Bohm-like theories seem more like an ideological metaphysical superstructure intended to salvage a philosophical outlook which seems to be untenable anyway.
Of course, the moment they do come up with different predictions is the moment they start becoming interesting as physical theories. The Bohm pilot wave theory did come up with some different predictions (and are, I believe, disproven). The decoherence/Everett theories not yet. If they don’t result in different predictions, standard QM will be preferred by most physicists because it is simpler and more elegant.
That’s a misunderstanding. Decoherence theories do not “introduce” the UWF; it’s already there in standard QM. What decoherence theories do is they discard the metaphysical superstructure of “collapse”, whereby branches of the UWF somehow (inexplicably) disappear, a-causally, and then get ignored. Decoherence theories are more elegant and parsimonious on a theoretical level, which is why they are preferred by many. As an example, please explain succinctly in a couple of sentences what causes the collapse of UWF in standard QM, and /or when it collapses, without using ill-defined terms such as “observation”. The “measurement problem” has never been resolved in collapse theories, it just gets swept under the rug. PS, I do not believe the pilot wave theory has been disproven. However it does indeed introduce some rather questionable entities, the “beables”.
NO COLLUSION
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