Monday, August 26, 2019

Anti-quantum-mechanical propaganda at Big Think

Like all platforms whose quality isn't carefully monitored and improved by a hierarchical system of competent filters, has become another Internet-media tool hijacked by mediocre activists – which almost entirely means deceitful, ideologically driven, far left activists – who are just pushy enough and will do everything to spread their stuff. Their knowledge of the actual science is shockingly poor.

Even when thousands of dollars per minute of content are flowing to such servers, the content may be expected to be less valuable than a vigorously and urgently used toilet paper if the quality control is absent so that even the most self-evident trash may get in. You can't be surprised that ludicrously wrong monologues such as
Space is dead: A challenge to the standard model of quantum mechanics
appear on that server. There are silly messages hidden in every other word over there and the density of explicit or implicit falsehoods is amazingly high. First, the title is composed of two parts. The first says that "space is dead" which is surely a "not really established" claim about quantum gravity while the second part is about a different issue altogether, the basic axioms of quantum mechanics.

These aren't really the same "topic", at least not yet. Quantum gravity is just an example of a quantum mechanical theory – or a special subclass of quantum mechanical theories if you wish. All serious researchers in quantum gravity accept all universal postulates of quantum mechanics and if some of them don't, they are extremely careful about their proposals how they could hypothetically violate these axioms without getting complete nonsense.

Also, the second part of the title talks about "the standard model of quantum mechanics". This is a completely illogical sequence of words indicating that the writer forgot what he was talking about and got stuck in self-referring loops. The reason is that quantum mechanics is already a theory – theories like QM are the ultimate stuff that theoretical physicists are constructing, filtering, and refining.

When they talk about "models", it means a more specific type of a theory. For example, the Standard Model of particle physics is a particular theory of a narrower type where the field content and the list of interactions is fully specified. But it's clear that a "model" in the ordinary sense isn't what the speaker has in mind. Instead, the self-referring contrived sequence of words "model of quantum mechanics" was chosen because the speaker wants to deny that quantum mechanics is already a theory at all. Instead, he wants to downgrade it to some heuristic speculation or a piece of arts that still needs something else, a real "theory", to become science. But that's demonstrably not the case. Quantum mechanics is a complete theory that defines which questions are scientifically meaningful and how to calculate the answers to these questions. No disagreement with the experiments has been found as of 2019; and similarly, no measurement that would be unanswerable by QM, even in principle, although there is evidence that one may get some nontrivial experimental answers, has been pointed out.

Some people may look for a "model of quantum mechanics" in a sense of another theory of a different kind, almost universally a theory in classical physics, that should replace quantum mechanics according to their plan. It's obviously impossible. Actual physicists don't do anything of the sort. They want to understand the correct theories that actually describe nature and not some simplifications, parodies, or caricatures – "models" in this sense of toy trucks – that may be good to promote the theory but that aren't good or accurate science from the scientists' viewpoint.

Serious physicists study theories or models themselves (which say something about the actual observations of Nature), not models of theories or theories of theories of theories etc.

The subtitle says
Since the idea of locality is dead, space itself may not be an aloof vacuum: Something welds things together, even at great distances.
Cute. But the idea of locality isn't dead. On the contrary, it's been alive since 1905 when it became a fact due to the special theory of relativity. That theory – backed by a huge and diverse body of experiments – established that locality and the ban on the faster-than-light signals is equivalent to the ban on acausal influences in which the future influences the past.

A theoretical physics PhD in the second half of the 20th century granted to someone who is "capable" of saying that "locality is dead" is exactly on par with a geology PhD given to someone who claims that the Earth is flat.

Relativity bans faster-than-light signals because they are, via the Lorentz transformation, a symmetry of Nature, equivalent to faster-than-light signals that go backwards in time. The non-existence of such effects is therefore a matter of basic consistency of the laws of physics (the absence of causally closed time-like curves). Indeed, such a ban means that the empty space must be completely empty – or at least, it must be empty of structures that would pick a preferred inertial frame. These prohibited structures include "anything like air, water, or other gases and liquids", "anything like crystals or solids", and "anything like a system of wheels and gears which is how many 19th century physicists imagined the luminiferous aether". Anything like a "network made of seemingly localized building blocks" that fills the vacuum has been banned since 1905. Not even "spin networks of loop quantum gravity" may get an exception. Like all similar naive examples of the aether, they've been dead since 1905.

Indeed, it was a key point of Einstein's revolutionary new understanding of electromagnetism that the aether was proven non-existent. That's how he got to his insights – by carefully thinking about the propagation of light – and anyone who denies that the aether as envisioned in the 19th century has been ruled out is denying all of relativity.

Locality precisely holds in the best non-gravitational theories of Nature we have – quantum field theories. In quantum gravity, whether or not locality precisely holds is a little bit trickier question. There are careful definitions that apparently allow us to say that locality holds even in quantum gravity assuming that "truly analogous conditions" to the conditions in special relativity are met. On the other hand, if locality is defined in some sloppy way, by some sloppy quantities, it's common that we may find out that e.g. the Hawking radiation violates locality. This violation may be shown to be an illusion in some finer definitions of locality, however. Similar comments apply to string theory's perspective on quantum gravity. Some straightforward notions of locality are invalid e.g. when we try to associate the strings to points simply because the strings are extended. But finer definitions of locality may be shown to hold even e.g. in string field theory.

At the beginning, the speaker defines his "realism" as
the belief that there exists an accurate description of Nature that is independent of our interventions, of our knowledge etc.
If the speaker were familiar with the basic theoretical physicists' terminology, he would know that the "belief" defined exactly in this way is normally called "classical physics". This is the phrase that I will use because I am a physicist, not a snake oil salesman who tries to produce a used sheet of toilet paper for thousands of dollars.

Now, classical physics – the framework of physics where the information about the state of Nature objectively exists (and is given by a choice of the state from a "phase space" as we call it) regardless of any observations and ideal observations may be assumed to be non-interventionist – has been known to be incorrect around 1925. Physicists were realizing that it was necessary to abandon classical physics in the previous decades – approximately since 1900. They figured out why all the basic types of ideas – that are still crazily promoted by "believers in classical physics" in 2019 – were unable to agree with all the known phenomena of the early 20th century physics at the same moment.

Perhaps due to some huge dose of luck, philosophers have built the vague conceptual foundations for the new framework of physics, quantum mechanics, already in the 19th century. Positivism founded by Auguste Comte was a branch of the empirical philosophies of science that usefully emphasized that all our knowledge about Nature comes from sensory perception – so sensory perception is what all of our arguments about the laws of Nature and about the state of the world must ultimately be reduced to. When it's so, it's rather natural to study the (probabilistic...) connections between the sensory perceptions (observations) directly, without assuming some intermediate "machine", an objective classical system that was assumed to exist even in the absence of observers.

To one extent or another, other top philosophers that have influenced physics were continuing in the tradition of positivism which turned out to be useful. Albert Einstein was primarily affected by Ernst Mach, a newer positivist from the late 19th and early 20th century, while Niels Bohr was – like Einstein – an avid reader of philosophers' texts and he was primarily building on the writings of the Vienna Circle (Wiener Kreis), modern 20th century descendants of the positivists that abruptly ended in 1936 (not only because of the obvious political reasons; watch Vienna Circle, exact philosophy in demented times).

In 1902, my first elementary school was just built (date under the clock).

The younger generation of the "true founders of quantum mechanics" who did it in the mid and late 1920s and who were born between 1900 and 1902 – Heisenberg, Dirac, Pauli, Jordan, Wigner, Eckart and others (lots of fathers of QM born in 1902 in particular) – was already much less keen on reading philosophers' texts. But they listened to Niels Bohr, a spiritual father of theirs, and credited him with many conceptual, new, and essential insights – often without realizing that Bohr has actually learned some of these deep general things from the philosophers. At any rate, when the generation of Heisenberg and even younger generations took over physics, there was no longer any useful – according to the top physicists – influence of "living philosophers" on physics. A broken calendar (with OK last three digits) is only correct once per millennium – and philosophers were already right around 1900. Let's wait through 2900 AD for two more glorious decades of philosophers who may contribute to physics.

By the 1920s, all physicists who were up-to-date already knew why all the "beliefs" by this speaker were wrong. In particular, it is impossible to perform non-interventionist experiments. Every observation unavoidably – and almost by definition – influences the observed system and does so irreversibly yet these interventions are essential for any discussion about the state and laws of Nature to be scientifically meaningful. So the specification "what an observation is" is an inseparable part of the application of the laws of physics.

Incidentally, his usage of the word "belief" has an understandable likely motivation. "Belief" sounds like a religion and everyone enjoys the freedom of religion. Except that in science, what is even more important than the freedom of religion is the freedom to point out that theories and "beliefs" falsified by the experiments are wrong – and that the people who are stuck with truly indefensible theories and "beliefs" are bad scientists if not crackpots.

The speaker also says that
due to the First World War and the predominance of some philosophy in the interwar era, [classical physics] that I believe to be true wasn't popular around the 1920s etc.
This is obviously a complete falsehood whose only purpose is to unjustifiably insult the ingenious physicists of the 1920s. The actual reason why classical physics was abandoned was that it was found to be incompatible with the experimental facts – the black body radiation, photoelectric effect, stability of atoms, spectral lines of atoms, radioactivity, interference properties of electrons, Compton effect, low heat capacity \(O(k_B)\) of each molecule, and more.

The reason why classical physics was abandoned by scientists – and it was being abandoned gradually between 1900 or so and the late 1920s – wasn't any "philosophers' preference" let alone the First World War. It was abandoned because all the carefully refined classical theories or hypotheses were experimentally falsified – or at least sufficiently specific classes of classical physical models were ruled out. That's how science including physics works when it's real science – and physics of the 1920s was real physics par excellence, unlike some neo-Marxist critiques of science from the early 21st century. Physics isn't decided on the First World War battlefronts or in the philosophers' bedrooms and everyone who is telling you something else is lying to you.
I am trying to talk in the way in which Niels Bohr was talking because he was the most radical of these [anti-classical-physics] thinkers.
It's a manipulation if not another outright lie to say that Niels Bohr was the "most radical" one among the thinkers who rejected the basic assumptions of classical physics. All physicists who were building the new framework of physics rejected the axioms of classical physics equally – namely completely. To say the least, none of them has dedicated a single day of their research career to the assumption that classical physics was correct, after all. The actual difference between Niels Bohr and his mostly younger friends was that Niels Bohr had been a keen reader of the philosophers' books so he was often using their jargon – and philosophers' jargon often sounds murky, ideological, or both.

As Catherine Chevalley has convincingly argued, all claims about Bohr's "obscurity" are compatible with the theory that the critics found it obscure simply because they were (or are) unfamiliar with the philosophers' writings that Bohr has considered to be his prerequisites; and all "genuine dissatisfaction" with Bohr's "ideological" statements may be explained by the critics' indoctrination by other philosophies, almost universally those philosophies whose corresponding physical theories and models were ruled out by the late 1920s – but these wrong philosophies began to spread like fire after the Second World War, anyway.

But the content of the opinions was pretty much exactly the same when we compare Bohr with Heisenberg, Dirac, Born, Pauli, Jordan, Wigner, von Neumann, and others. They just understood that the era of classical physics had been over. The reasons are scientific – the previous theory has failed some tests – and even if the positivists' comments sounded ideological, this ideology has been vetted by the scientific method.
Let's talk about what it means to be a [non-classical physicist]. It means to believe that [classical physics] is too ambitious and too hard...
No, that's simply another lie. Classical physics is in no meaningful way more ambitious than quantum mechanics. Quantum mechanics is clearly a description of Nature at a deeper level than its classical approximation – just like relativistic physics is deeper than the non-relativistic approximation and the atomic description of thermal phenomena is deeper than the approximate, macroscopic thermodynamic description in the "thermodynamic limit" – which is why it's only correct to say that quantum mechanics is more ambitious than classical physics, at least more intellectually ambitious. It's just the other way around than the speaker says.

Incidentally, quantum mechanics generically makes predictions that have some uncertainty. But sometimes, quantum mechanics makes more unambiguous predictions than all "analogous" classical systems. The "quantum game theory" is full of examples of entangled systems (take e.g. the pentagon of cups) where a measurement is guaranteed to be precise and predictable. But it's often another, perhaps opposite, result than predicted by classical arguments.

Quantum mechanics and classical physics are incompatible frameworks of physics and again, the actual reason why classical physics has been abandoned is that people have realized that it's incompatible with the body of known phenomena, even with a bunch of very elementary observations. The claims by the speaker that physics went in the direction in which it went because of some nepotism among philosophers, because of some fights on the First World War, or because of a low ambition or weak skills of the physicists of the 1920s – all these things are provably full-blown lies and a dirty anti-physics propaganda.

Physics went in the direction that it has picked because the experimental facts dictated that no other direction was working well. Physicists have found and picked the simplest and most natural framework and theories that hadn't been ruled out yet. And the people in 2019 who are genuinely failing to understand why it's so are not failing because they are ambitious, war-avoiding, philosophy-avoiding, hard-problems-seeking geniuses or seers – but instead it's because they are just people with a low intelligence that is insufficient for the understanding of modern physics. If they try to sell their clear vices as virtues, it may be considered deception.
Electrons, nuclei... but what are these things? We often get confused when we talk about these things, the talk is stretched etc.
Maybe people who defend the return to classical physics in 2019 get confused all the time, whenever an electron appears – because their "beliefs" are incompatible with most of the actual facts about electrons – but all competent high-energy, particle, atomic, and even molecular and condensed-matter etc. physicists understand what an electron is. It's a nearly elementary concept connected with observations that are being made – as well as with the actual theories that are being used to explain the observations. So physicists not only know the word "electron" but they may assign truth values to a huge spectrum of statements about the electrons – how these particles manifest or don't manifest in experiments.

The conclusion that "I don't understand the electron" is another sign of someone's incompetence, not his depth. Physicists understand electrons and the understanding is better than e.g. the understanding of "planets" because electrons are more fundamental and more well-defined than "planets". To say the least, no real physicists are arguing with each other whether Pluto is an electron.

Electrons are represented in some way in Schrödinger's or Pauli's model of the atoms or in the one-particle Dirac equation or in condensed-matter models of metals or crystals or in QED or the Standard Model and these are not the ultimate theories. String theory almost certainly is but it is not fully understood to determine what it exactly predicts about the electrons. So one can't claim the "ultimate, complete, and precise knowledge" about electrons is available so far. But that's always true in science and it doesn't mean that "physicists don't know what an electron is". If someone claims that electrons are less understood than some complex objects, it proves that he doesn't understand fundamental physics at all. He doesn't understand that fundamental physics actually gives a clearer, purer, more accurate, more precise, and less convention-dependent understanding of elementary objects in Nature than any more "emergent" theory gives about the more complex systems.
[Quantum physicists] are impatient and have low ambitions.
Someone who has proposed "5-year deadlines" after which each physical theory is banned is talking about "impatience". Nice. Low ambitions again. Again, there is absolutely no impatience or low ambition about quantum mechanics. Instead, one may formulate sufficiently well-defined questions, e.g. "whether the random outcomes of the spin measurements may be due to hidden variables or are they really random", and accumulate evidence for and against both possible answers. When it's done, the scientific answer emerges and the scientific answer is that quantum mechanics is right (and the random outcomes are genuinely random) while classical physics (and various proposed explanations with hidden variables) are wrong.

This conclusion is exactly on par with the conclusion that the Earth is round, not flat. We just carefully look at the phenomena, possibilities, and evidence – and the correct answer emerges. Someone may have some personal reasons to dislike the results of scientific research and the answers that it has provided us with and launches a pathetic jihad to sling mud on science so that the mud gets stuck in the minds of the stupid laymen – but this activity is a classical example of what science is not. You can arbitrarily and unjustifiably claim that the Flat Earth is ambitious, ethical, patient... but you won't change the fact that the Earth is round.
Again, I am trying to emulate Niels Bohr which is hard, not only because of the accent but because he was mystical.
Bohr had some accent in English because he was Danish. To try to use his nationality as an argument against his ideas is absolutely pathetic. The speaker doesn't speak Danish at all – and indeed, in the quantum revolution, the Danish and German languages could have very well been more important than English which is why it's absolutely silly to discuss someone's knowledge of English at all. Why doesn't the speaker show us how good his Danish is? Can he translate the comments by Bohr's wife for us?

Niels Bohr wasn't mystical in any tangible way. He was a physicist with a strong background taken from philosophers' books but those were positivist philosophers who were as empirical and non-mystical as you can get. All these negative claims against Niels Bohr are just childish insults and only totally moronic visitors of are affected by them (but yes, I am afraid that the number of such visitors is high).
Niels Bohr said that we may only describe how we interact with Nature and he was at risk of contradicting himself.
He said it because this is what physics has established in the transformative 1900-1925 years. It's been a scientific fact since the late 1920s.

Yes, one may say that there's a potential "risk of contradictions" at some stage of one's understanding of quantum mechanics. But a "risk of contradictions" isn't a problem – much like someone's fear that the Earth could vaporize in 12 years isn't a problem. Only an actual contradiction – or a complete proof of a contradiction – would be a problem. There's no such contradiction in quantum mechanics and no such proof. It may really be proven that no such contradictions arise. Quantum mechanics may be said to move "dangerously close to a contradiction" but there is nothing wrong about it – instead, it is indeed a sign that it is a deep theory, one that maximally "exploits" the freedom that mathematics offers.

Being close to contradictions while avoiding them is a good sign for a theory. String theory manages to achieve the same, at an even more intense level than ordinary basic quantum mechanics – one may even derive the critical dimension from this principle etc. See also Milton Friedman's F-twist.

Quantum mechanics avoids the contradictions. A contradiction would be two different eigenvalues attributed to exactly the same observable. That can't ever happen, according to any quantum mechanical observer. Quantum mechanics demonstrably implies that if you measure the very same observable twice, with no interfering measurement in between, you will get the same result with the 100% certainty. Instead, Bohr's complementarity really means that different observers typically ask questions that aren't quite the same – which also means that their disagreement isn't ever a sharp contradiction. Different questions have different answers. Slightly different questions have slightly different answers – or a small probability to have very different answers.
Bohr was seeking new laws of physics, arts, and lifestyle...
It may have been true but this mixture is a demagogic sleight-of-hand because it indicates that Bohr's physics comments were influenced by the ideas about arts and lifestyle, and therefore failed to be rigorous enough, pure science. That's untrue. Bohr knew how to distinguish and separate hard science from other things – in fact, this is really the thing that positivists (the philosophers) really were very careful about.
Louis De Broglie had an obvious idea. The wave function is a pilot wave...
It's obvious in the sense that it's similar to what the recently abandoned theories – classical theories – had been saying, and in fact, to what Erwin Schrödinger was incorrectly saying, too. Only "objectively real waves" may exist so the wave function must be one, too.

But it's not an objectively real wave. It's a wave of probability amplitudes, as Max Born has quantitatively explained. The good physicists were figuring out that the new mathematical variables wouldn't be "objective" already before 1925. The year 1925 only meant that Heisenberg (plus Jordan and Born) found a mathematical version of these general ideas that quantitatively worked for the first time. You can say that Heisenberg's 1925 papers were the culmination of the work started by the 19th century philosophers that continued in Bohr's atomic model of 1913 – the basic philosophy was determined from the 19th century while the physical realization was getting more realistic, particular, and quantitative.

Some people like de Broglie hadn't gone through all this thinking before 1925 in which the wrong alternatives were eliminated. It was unsurprising for some revisionism to appear – attempts to be a parasite living on the recently triumphant quantum mechanical concepts while trying to undo the physical insights associated with them. So the pilot wave theory "had to" be proposed at some moment.

The pilot wave theory was ignored by the real, active physicists because they knew why it was wrong – it was an attempt to revive the old framework that had been abandoned. It was an "elaborate" attempt that tried to use much of the mathematics of quantum mechanics. But it's unsurprising for such things to be wrong. It's completely analogous to "versions of creationism trying to emulate Darwin's theory". One may assign special characteristics to God so that He will tend to distribute bones and properties of species that resemble the mechanisms in the evolution theory. But it's more likely – even though it's not guaranteed – for the correct theory to actually use the ideas before the incorrect theories do. If one of the theories predicts the patterns much more naturally and with many fewer assumptions, it's probably the more right way to encapsulate the "winning arguments and patterns" into a full-blown theory.

(Note that string theory and quantum field theory generally have nearly equivalent predictions for doable experiments, at least the qualitative features of these predictions. But string theory wasn't constructed like an emulation of quantum field theory – which was the how the pilot wave theory was born. String theory has very different technical initial assumptions and the QFT-like and Yang-Mills-like etc. conclusions were nontrivially derived from these new assumptions – so the agreement of string theory and QFT at low energies looked like "good luck". That's why it's completely sensible to say that the newer theory among the two, string theory, is a more likely utilization of the same observed patterns than the historically older one, quantum field theory.)
The pilot wave theory tells you everything, what, when, and how.
This is just completely false, too. The pilot wave theory is almost completely ill-defined; it tells you almost nothing and this lack of predictive power is pretty much rigorously provable. It doesn't say what determines the initial position of the "real" electron, why its initial distribution matches that expected one from the initial pilot wave. It doesn't tell us how the no-longer-relevant pilot wave is "swept" after the particles are observed or absorbed. Because of these two things – the missing description of anything related to the collapse – the pilot wave theory contributes zero to a solution of the non-problem that the [classical physicists of 2019] call the measurement problem.

Also, it tells us nothing about how to pick the "beables" for a more general system with spinning particles, fields, strings, or membranes etc. It is an emulation of quantum mechanics that must be invented from scratch ad hoc, differently for each new type of a quantum mechanical theory. The pilot wave theory is a strategy to fake quantum mechanics by a classical theory – which is bad enough – but it is not even a complete description how to perform this faking procedure.

Unsurprisingly, Bohmian replacements for quantum field theory or other theories can't really work, especially because they're almost 100% certainly predicted to violate the Lorentz symmetry which is lethal for the theories of particle physics.
Einstein discovered entanglement.
That's just plain nonsense. He just invented the first term for this trivial and omnipresent feature of almost all states – the spooky action at a distance (he coined that phrase in German). He coined the term because he felt uncomfortable about the very existence of this phenomenon.

But entanglement just means that the state of a composite system isn't a simple tensor product \(\ket \alpha \otimes \ket\beta\). It is a sum of such products and the number of terms must be greater than one. Consequently, some correlations are predicted for the two systems. "Entanglement" is just a description of a general set of nonzero correlations in terms of pure states – and the concept of correlations had been known for centuries. All quantum physicists knew that almost all quantum states of a composite system obeyed this "non-factorizability" condition. They just didn't feel the need to use a term for this trivial property because this new buzzword only seems useful for falsely justifying some incorrect claims about/against quantum mechanics.

In particular, the singlet state of two spins \(\ket\uparrow\ket\downarrow - \ket\downarrow\ket\uparrow\) was already known to Pauli in the mid 1920s. All the wave functions for pairs of spins encoded in the Clebsch-Gordan coefficients were known (plus their importance was understood) by 1941 as well, exploiting some mathematics that had been written down since the 19th century. You probably didn't know but both Clebsch and Gordan were born in the 1830s! If you want a related phrase named after physicists born in the productive year 1902, over 60 years after Clebsch and Gordan, why don't you look at the Wigner-Eckart theorem? At any rate, it's ludicrous to say that Einstein let alone Bell discovered entanglement or these particular entangled states.

Einstein only "invented" a buzzword for popular books (which got repeated in hundreds of popular books that make mostly incorrect claims about quantum mechanics), not a new discovery in quantum mechanics of composite systems that would be appreciated by professional physicists. His and EPR examples were trivial for quantum physicists and all Einstein's and EPR's opinions "how things should ultimately be" were demonstrably incorrect. In particular, their claims that entanglement contradicted relativistic causality were clearly wrong.
The definite result [of the experiments etc.] is that locality is false.
No, this is completely wrong. As everyone who has deserved a theoretical PhD since 1905 knows very well, locality is absolutely true and precise, at least in all non-gravitational theories – both in classical theories and quantum theories. The principles of relativity and their consequences are very fundamental and you can't justify an exemption just by babbling that with the word "quantum" (that you don't even want to allow, to make it even more preposterous), there should be an exemption. Such an excuse is worth nothing. Of course the principles of relativity have to hold and do hold in realistic quantum mechanical theories, too.
It has nothing to do with whether you believe in quantum mechanics.
Right, locality has nothing to do with quantum mechanics or a "belief" in it. Except that the speaker's opinion about the actual truth value is wrong in all cases. Locality is a fact about Nature because of the special theory of relativity. Quantum mechanics is orthogonal to that and realistic theories must obey and do obey both the principles of relativity and the postulates of quantum mechanics – and quantum field theories are the simplest theories of that kind (which are enough for all non-gravitational physics).
If you are a [non-classical physicist], you can't answer the question how the information gets back and forth [between the two entangled measurements].
That's also completely false. Quantum mechanics allows us to calculate how much information is going in between the two (spacelike-separated) places and the amount is precisely zero because no probabilities of observables are affected by decisions made in a spacelike-separated region. Some extra variables that someone imagines to exist may be affected superluminally but these extra imagined variables may be shown to be unphysical – unlinked from the observer's observations of observables – using the axioms of quantum mechanics that remain compatible with all experiments and apparently complete. So one shouldn't really derive anything from these imagined (typically hidden) variables simply because they're not a part of science, exactly for the same reasons why the Tooth Fairy isn't a part of science. Whether the Tooth Fairy flies superluminal airlines is irrelevant for the fate of relativity because she doesn't exist in the scientific sense. The entanglement has nothing to do with the transfer of information at the moment of the measurement or so – there isn't any (all the correlations are consequence of the co-existence or joint birth of the subsystems in the more distant past, not of any recent communication or interaction) – and quantum mechanics gives us the tools to rigorously prove and calculate the statement I just made. Every claim that there is something disputable about that is just a non-expert's fog, a layperson's misconception, a lie frequently repeated in junk-rated popular books.
The [classical] theories have to tell you how the information moves faster than light. Is that testable?
You bet, it's rather easily testable and every theory that generally predicts a generic, omnipresent superluminal propagation of information – because it doesn't have a tiny glimpse of a reason why such signals should be banned or almost banned – is falsified immediately just like a theory that predicts that almost all astronauts will see a flat Earth.
Maybe the prediction is untestable because the results are random.
This wishful thinking is not really possible because by denying the fundamental quantum randomness, these classical theories say that the results aren't really or fundamentally random. They're just some phenomena and if the superluminal transfer of the information were allowed by the laws of physics, it could work even in repeated or magnified phenomena with some "constructive interference" of the evidence, i.e. phenomena that aren't alternating randomly to make everything cancel. If there's no actual reason why things will cancel, they just won't cancel. A fundamentally non-relativistic theory will produce, even through its approximations, theories whose Lorentz-breaking terms are mostly of order one and those are simply excluded trivially and immediately. Not to be able to derive this simple conclusion means to be not to be competent as a 20th or 21st century theoretical physicist.
It tells you, if you are [classical physicist], that locality is dead and basically space is dead.
Again, an overwhelming body of evidence told the people that they just couldn't keep on being classical physicists if they want to be scientists because scientists abandon theories that have been experimentally refuted – and classical physics was experimentally refuted. In the same way, non-relativistic theories i.e. theories with superluminal signals were refuted by the evidence in favor of the 1905 special relativity so everyone who wanted to remain a scientist had to throw away the contradictory beliefs in nonlocality etc., too.

Whoever believes in 2019 that the world is non-local or non-quantum – or even both – simply fails to be a scientist.
But something deeper is going on.
Too bad the monologue was the opposite of an example of the depth – it was a defense of the view that one should simply ignore all the 20th century science and mentally return to the 17th century. I surely don't think that an effort to ban one century of ever deeper and more correct ideas is an example of deep thinking. It's an example of the shallowest and most intellectually embarrassing ideas imaginable, a populist demagogy that wants to persuade the stupidest listeners that their naive misconceptions resulting from their low intelligence are deep and cool. They are not but lots of very stupid people will love to buy totally invalid books on physics as long as these books will tell them the untruth that the morons are deep geniuses.

One can see how the publication of books by authors who aren't constrained by any genuine knowledge or moral principles evolves in time. First, they publish books that "just" attack the scientific achievement of theoretical physics of the recent 40 years. But the number of dumb readers who care about the recent 40 years at all is still too small. So assuming that they have no natural enemies who affect things, these writers are trying to increase the number of readers into a wider spectrum of even more hardcore morons by extending the target of criticism to all of physics of the recent 90 years, and so on. At this rate, similar authors will sling mud on heliocentrism around 2040 – in order to attract hundreds of millions of readers, the most hopeless morons on Earth.

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