Tuesday, May 22, 2018

Dumb tirades about a "liar paradox" in quantum mechanics

A reader has linked to another weird text about the foundations of quantum mechanics that was published in Scientific American,
Quantum Physics May Be Even Spookier Than You Think
and that describes a paper combining wrong claims about non-locality of quantum mechanics, wrong claims about "quantum mechanics that just tells us about the averages", with some new superstitious hype that makes quantum mechanics "diabolical" and not just "weird", and with drunk suggestions that quantum mechanics should have two states and not one state.

The title uses the concept of "escalating hype" – quantum mechanics is "even spookier than you think" – that basically emulates the language of the climate alarmists. Whenever their latest predictions and other claims are proven to be completely wrong once again, they double down and produce even more absurd claims that the "catastrophes are even worse than previously thought".

In this way, they expect the decrease of their influence – due to the recently invalidated prediction – to be compensated by the "increased threat" that they try to spread. Apologies but this isn't how honest scientists operate – and sensible consumers of science simply eliminate such sources of information from their list of credible or usable sources.

The stuff that the anti-quantum zealots are writing is increasingly idiotic and incoherent. I don't think it makes sense to waste time with every similar paper that makes it to the media.

A related paper by a similar, self-referring group of mostly self-citing babblers was published in January:
Interaction-Free Effects Between Distant Atoms
One first cute improvement appears in the list of authors. Aside from Aharonov, Cohen, and Elitzur – who have produced lots of garbage about "weak measurements" over the years – another stellar co-author has been added, the crackpot-in-chief Lee Smolin.

They discuss two atoms, one excited atom and one in the ground state, that have – after some time (which is incorrectly quantified) – a 50% probability to switch their "ground/excited" labels by a photon that is emitted by the excited atom and absorbed by the atom in the ground state.

Now, these four men claim that this setup is a realization of the "liar paradox".
Let us summarize. The indication of atom A/B that it has never emitted/absorbed a photon, which may naively suggest that it could not be entangled with B/A, is the result of this very A-B entanglement. The classical liar paradox stemming from Epimenides’ claim that “all Cretans are liars” is not necessarily absurd when stated by a quantum-mechanical Cretan (see also [13]).
Holy crap. They basically say
The entangled state of 2 atoms is equivalent to the original "not exchanged" situation; and it's also equivalent to the "exchanged" situation. So the "exchanged" and "not exchanged" situations imply each other, and that's a paradox.
This reasoning is nothing else than another symptom of the soft feces in the authors' skulls. In reality, the superposition state \(\ket\alpha + \ket\beta\) is obviously "equivalent" neither to \(\ket\alpha\) nor to \(\ket\beta\), so there's no way to show that \(\ket\alpha\) and \(\ket\beta\) follow from each other. When the states \(\ket\alpha\) and \(\ket\beta\) are orthogonal to each other, the physical situations they describe are mutually excluding, and no consideration of any superposition can change the fact.

The fact that \(\ket\alpha\) and \(\ket\beta\) are exclusive is their relationship – given by the vanishing inner product – and any consideration of a third vector such as \(\ket\alpha+\ket\beta\) is a pure distraction. One only gets distracted so that he "forgets" or "overlooks" the orthogonality is a sign that one simply cannot focus and his brain is inadequate for physics.

If one determines that the physical system is in the state \(\ket\alpha\), he knows it can't be in \(\ket\beta\), and vice versa. If he determines the physical system is in \(\ket\alpha+\ket\beta\), it may be both in \(\ket\alpha\) and in \(\ket\beta\), but those two options are still mutually exclusive.

It's spectacularly obvious that quantum mechanics, when used properly, simply cannot lead to any logical paradoxes of this kind. But despite this self-evident fact, these four authors write over 60 pages (on my screen) of similar garbage. Their system is nothing else than another rudimentary two-level system that were discussed in the Feynman lectures except that Feynman's undergraduates were supposed to solve these systems correctly, while Smolin and his colleagues simply don't have the slightest chance to pass this basic undergraduate test.

The only correct sentence in the paper is a sentence in which the authors refer to themselves,
"all cretins are liars",
but even this sentence isn't quite right. It's misspelled. On top of that, it's not original because Epimenides is cited as the source of that insight.

I think that pretty much all people who use quantum mechanics to do some real stuff know very well that papers like that are worthless rubbish. But there are so many idiots in this "quantum foundations" would-be field and so many idiots in the "infrastructure" surrounding this field – and the Academia – that they are doing fine when they market this garbage as a scholarly activity.

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