I was led to see a preprint by a Spanish anti-quantum zealot on steroids called Pablo Echenique-Robba called
Shut up and let me think. Or why you should work on the foundations of quantum mechanics as much as you please (August 2013)which is nothing else than an inconsistent, dishonest, and demagogic assault against quantum physics and everything fundamental we know about it, and against many pillars of the scientific method. This Spanish rant has elevated my adrenaline level substantially but even now, once the level has returned close to the long-term average, I am still amazed how it's possible for the arXiv to allow such rants with zero scientific content to be posted in the quant-ph sub-archive. The endorsement system is clearly not working too well.
The universal postulates of quantum mechanics, its probabilistic, proposition-based character, and its intimate connection with linear algebra are the main targets of the Spanish crank's assault when it comes to the ideas (sorry, I refuse to memorize his contrived name and/or contaminate my clipboard with it). Richard Feynman, Niels Bohr, and the authors of almost all textbooks of quantum mechanics (including Cohen-Tannoudji et al. 1977a,b, Landau and Lifshitz 1991, Messiah 1961a,b, Newton 2002, Sakurai 1994, Shankar 1994) are victims of his ad hominem attacks, much like Berthold-Georg Englert.
On the contrary, the pop-science types who don't understand quantum mechanics – like Sean Carroll etc. – are favorably quoted.
Everything that this hardcore Spanish crank tries to disagree with is right: the foundations of quantum mechanics have been settled and completed since the years 1926-1927. The continuing efforts to "clarify" the foundations of quantum mechanics is philosophy – in the pejorative sense – and a bad philosophy, in fact. The people who think that they're changing the foundations of quantum mechanics are lousy thinkers and bigots who are incapable of understanding that the framework of classical physics has been falsified for almost 90 years and it will never return again. Quantum mechanics requires one to think differently.
The author isn't ashamed to admit that the primary goal of this rant is to spread delusion and to help other demagogues. The abstract "denounces" all the valid propositions about the foundations of quantum mechanics and at the end, it adds this "cute" explanation of the purpose of the rant:
...I provide some arguments that you might want to use the next time you confront the mentioned "opinions".Sorry but scientific papers are not written with the purpose of "providing people with arguments they might use" in confrontations. Legitimate scientific papers have the purpose to reveal the truths about Nature and present evidence and arguments supporting those, regardless of whether or not the reader joins a confrontation. The specific description of the purpose of the paper as "weapons for confrontations" is a proof that the author isn't impartial, a claim that is confirmed by every single sentence on the remaining 30+ pages of the rant.
He is not only wrong but breathtakingly inconsistent – I would say that even a layman must be able to see that. The Spanish crank repeats that he is against the authorities several times. However, every section and subsection of his rant begins with a (highly cherry-picked and misinterpreted) quote by an authority and the rest of the preprint is all about quotes, too.
He describes all the lousy thinkers incapable of understanding quantum mechanics – like himself – as people with a "restless intellect".
On one hand, he agrees that "of course, scientific issues are not decided democratically". On the other hand, he interprets chaotic results of a poll on quantum foundations as a proof that something remains unsettled about the foundations of quantum mechanics. But polls can't imply anything of the sort. The only thing that the poll shows is that a very large fraction of the respondents are incompetent (that's true about the majority of the people who claim to "study the foundations of quantum mechanics") or at least deeply confused, and/or that some of the questions were not scientifically well-defined questions.
The Spanish crank "fights" against the shut-up-and-calculate dictum coined by David Mermin (and often attributed to Richard Feynman who surely agreed with the spirit of it). He tries to present Feynman's opinions about the foundations of quantum mechanics as inconsistent ones. But there was absolutely nothing inconsistent about them. Whenever Feynman said that no one understands quantum mechanics, he meant that all the imagination we have been trained to for millions of years of evolution fails, at least in some contexts, when it's supposed to understand how quantum mechanics fundamentally works. It's because all of our hardwired experience was using classical physics and quantum mechanics just fundamentally disagrees with the basic assumptions of classical physics such as the "objective reality". This interpretation of Feynman's words is completely clear in this video, for example. Feynman has never meant that some essential questions about the foundations of quantum mechanics remain unresolved by science.
This Spanish would-be physicist uses lots of emotionally loaded and totally untrue words – e.g. that "quantum mechanics is a conceptual mess". Quantum mechanics is the most robust framework for science that we have. It's perfectly understood, its predictions are the most accurately verified predictions of all of science, and it makes a perfect sense. Quantum mechanics tells us how knowledge (statements) is translated into properties of the state vector and operators; how to apply linear algebra to calculate other properties of the physical system – i.e. how to answer that some operators acquire certain eigenvalues; and how to use the resulting complex probability amplitudes to compute the probability that any observable proposition is right. It also tells us that it's scientifically invalid to ask any other question that doesn't respect this basic framework.
The Spanish chap still hasn't understood this basic thing. There is absolutely nothing messy about quantum mechanics. It's as well-defined as you can get. A bigot may be offended by the fact that the foundations of physics have been dramatically transformed in the 1920s but his dissatisfaction can't change anything about the current state of the physics knowledge and he can't change anything about the fact that claims that quantum mechanics is a mess are pure, shameless lies.
It's funny to see that the Spanish crank is offended by the very fact that a living person would dare to say that quantum mechanics just works. At the end of Section 2.1.0, we read:
Despite these encouraging words, the paper by Englert (2013), which was published in the arXiv curiously the same day as the first version of this manuscript, is the living proof that the "Shut up and calculate!" school is strong and thriving. We could delight in many of its paragraphs, but it actually su ces to read the unusually short abstract:This statement by Englert – it's just the abstract of Englert's paper – is so stunning for the Spaniard that he turns speechless: no comment is added. Of course, the bastard Spaniard doesn't even try to react to anything inside Englert's paper, like those 80 equations and clear explanations why no problem remains to be solved about the foundations of quantum mechanics, why it's local, and what's wrong with all the "realists'" interpretations of everything in quantum mechanics.
Quantum theory is a well-defined local theory with a clear interpretation. No "measurement problem" or any other foundational matters are waiting to be settled.
The attacks on Richard Feynman are repetitive. For example, it is suggested that the "shut up and calculate" philosophy was designed to make people stop thinking:
Even if one grants Feynman some rhetoric benefits, the appeal to "stop thinking" is a truly remarkable advice from one of the most popular scientists of his time.Feynman's popularity boiled down to his ingenious mind as well as some features of his personality, e.g. that he wasn't afraid to tell idiots similar to this Spanish one that they are idiots.
But concerning the main accusation by the Spanish "thinker" above, "shut up and calculate" doesn't mean "stop thinking". It means "stop babbling vague nonsense", the kind of crap that the Spanish crackpot's preprint is exclusively composed of. There is no thinking involved here – or at least nothing that could be called "thinking" according to the standards of Richard Feynman. It's just a continuous stream of emotions and ad hominem references written by a pompous fool. I don't call such activities "thinking". The inability to understand that the evidence implies that quantum mechanics is a complete, well-defined, and settled framework for physics proves someone's inability to think, not his thinking.
Incidentally, there is a high degree of correlation between being inexperienced and between paying lip service to these deluded proclamations about the need to revise the foundations of quantum mechanics (e.g. pro-quantum Berthold-Georg Englert is much older than the Spanish anti-quantum bastard) – even though some well-known examples of older physicists who are getting senile so they start to repeat nonsense about/against quantum mechanics exist, too.
The arrogance of the Spanish "physicist" is just totally incredible at many points. For example, Feynman was trying to explain that quantum mechanics implies that only probabilities can be computed. Hypothetically, it may be just a limitation of a current layer of approximation but, as Feynman said, it seems more likely to him that this is a property of valid physics theories that will stay with us. The quote
So at the present time we must limit ourselves to computing probabilities. We say "at the present time", but we suspect very strongly that it is something that will be with us forever – that it is impossible to beat that puzzle – that this is the way nature really is. (Feynman, 1963a, p. 10-1)is reproduced in the Spanish paper. What is the author's reaction to it?
And you probably met this objection or similar ones before: The mystery is irreducible, the puzzle is eternal, it is impossible to crack the problem, and so on and so forth. This is the central tenet of the Copenhagen interpretation, as we will see later.Holy cow, what a breathtakingly aggressive simpleton. I just can't believe. All the available scientific evidence suggests that Feynman was right and no "deeper" description that would refuse the probabilistic character of quantum mechanics may exist. It was certainly not found in the 50 years that followed the day when Feynman wrote the sentences above. I am talking about the real scientific evidence, careful analyses of theories and classes and theories, their comparisons with the empirical data. Real evidence can't be beaten by a superficial, vague, misleading, mostly unrelated, demagogic, general tirade about the human progress.
I will not take too much time to discuss this anti-rationalistic argument. It is too weak an adversary. Let me just mention that nobody has ever proved such a thing about anything. So far, we humans have been able to slowly but steadily understand more and more of nature's secrets, and it doesn't look to me that QM will be special. [...]
The discovery of the framework of quantum mechanics is the most important advance in physics of the 20th century – and probably the most groundbreaking development in the history of science – and Feynman just summarized one of its key properties. To say that such a comment by Feynman is "too weak an adversary" means to be a hopelessly fanatical anti-scientific bigot on steroids. It's not some weak disputable statement. It's an existentially important insight about how the Universe works. Average chimps would probably be able to understand this fact more quickly than the Spanish crank and they would find him too weak an adversary.
And the argument that no need for a probabilistic description was found before quantum mechanics? It's partly true, partly false – the microscopic understanding of thermodynamics, statistical physics, makes it necessary to think in terms of probabilistic distributions and probabilistic interpretations of statements – but even if we decided that quantum mechanics was the first theory that showed that the probabilistic reasoning was fundamental, there wouldn't be anything wrong about it. Every important insight is discovered for the first time at some moment. Quantum mechanics is the first scientific framework that makes probabilities fundamental. It's also the last one because there won't be any non-quantum framework in physics, ever. But just that a theory has no precedents doesn't mean that there's something wrong with the theory. Every groundbreaking enough discovery in science is "unprecedented". There had been no precedent of a theory that explained the origin of species via evolution before Darwin's theory. There had been no theory that the Sun would be in the center of the planetary system before heliocentrism. Those discoveries were made at some points. They were made for the first time. Only a complete imbecile may think that just because they were new, they had to be a "weak adversary".
Some additional paragraphs are dedicated to the idea that Feynman couldn't possibly mean what he said. Be sure he meant it, Spanish bigot.
The deluded man adds literally dozens of pages of pure rubbish about his idea that science isn't about making predictions, his idea that we must talk about things that are unmeasurable if a "thinker" similar to himself commands us to do so, and so on. I don't have the nerves to comment on all this junk because that would force me to read the junk again. I just end up saying that on the title page, this über-imbecile is listed with five affiliations. Sorry to say but this multiplicity is a piece of evidence that Spain is an inferior nation in the state of complete mess, indeed.
Sabine Hossenfelder wrote a reaction in which she tries to position herself in the middle between physicists and "researchers" like the Spanish one – that's a very politically correct and populist place where many not-quite-independent thinkers want to stand. So she says that she's OK with a theory that produces the right predictions but adds something that contradicts everything she had written previously. I don't want to spend another 30 minutes by discussing all the wrong opinions she holds about science in general and modern physics in particular because there are just too many and it's a waste of time.