Saturday, November 05, 2016

Weinberg's new calls for an overhaul of quantum mechanics

Someone sent me a three-day-old video with almost 1 million views – Is This What Quantum Mechanics Looks Like? – which claims that some jumping silicone oil droplets on a wavy surface is what quantum mechanics fundamentally looks like. Over 99% of those who voted on this pseudoscientific video have upvoted it. Well, I surely didn't. It's despicable when this anti-science is sold as science.

But I have largely surrendered. It makes no sense to write new explanations why oil droplets are nothing like quantum mechanics because a few thousand people read my texts, only a fraction understands it, while millions of stupid people want to hear something else than the correct physical proofs of the truth. They want something that confirms their stupid prejudices and their fundamental misunderstandings of modern science.

And it's not just this basket of one million of morons who have watched the aforementioned bogus video. As they are getting senile, numerous star physicists are helping to amplify this idiocy as well. Sadly enough, Steven Weinberg has been increasingly fitting this description in recent years. John Preskill recalls that when he was a student of Weinberg's, quantum mechanics was fine for Weinberg. It's no longer so and in an interview for, Steven Weinberg demands an overhaul of quantum mechanics.

Great. So the interview tells us that he's no longer happy about quantum mechanics and he's no longer dismissive of critics of quantum mechanics. You ask Why. The first answer:
One reason Weinberg thinks there’s a need for a new chapter in the quantum story is that those who think everything is fine with quantum mechanics take different sides in the debates about it.
It's just so painful and pathetic. How can someone whose achievements have turned him into a top 20 twentieth century physicist end up with this totally mushy, illogical, stupid, sociological, ad hominem argument? Is Weinberg really saying that something must be wrong with quantum mechanics because different people disagree what quantum mechanics actually says?

How can you blame quantum mechanics – or its founders starting with Werner Heisenberg – for the stupidity of other people? If I (or Werner Heisenberg) could make all these cranks shut up, I would probably use the opportunity. But I don't have such tools. Perhaps thankfully so: If I had such tools, they would almost certainly have the same tools to silence those who actually understand quantum mechanics, too. ;-) Every complex enough theory – and perhaps every theory – is being misunderstood, misinterpreted, misapplied, and abused by someone. String theory's prediction of extra-dimensional space is misinterpreted by the spiritual hacks who say that the dimensions are differently cooked spirits, among other things.

Climate alarmist nut jobs are misinterpreting thermodynamics and climatology by saying that it implies that the Earth will evaporate by 2055 or similar things that these crackpots spread everywhere. Does their disagreement with other people who use thermodynamics imply that something is wrong with thermodynamics? You can't be serious, Prof Weinberg. I may have picked more realistic examples but you can surely do it yourself.

The interview with Weinberg almost exactly matches this October 30th, 2016 Petrusky lecture. At 17:40, he says that he is no longer fine with QM etc. Hat tip: "Steven Weinberg doesn't like quantum..." (a blog post elsewhere).

This is not only about quantum mechanics. You're basically switching from the scientific way of thinking about Nature to the brain-dead postmodern philosophers' mode of thinking – or, more precisely, their fight against thinking. You have criticized those people so crisply – I've loved so many texts of yours, including Dreams on a Final Theory – and now you're doing the same thing. You are degrading yourself into a parrot who repeats the consensus or average opinion of 50 other people. You used to be several categories above virtually everyone else.

The rest of the interview is the usual collection of the unscientific whining about quantum mechanics. Something must be wrong with quantum mechanics because the right theory should be
determinist; realist not instrumentalist; have one history; independent of observers; intuitive; not weird, and so on, and so on.
Well, you may try to dictate Nature what laws She should obey but Nature replies unambiguously (as the evidence has unambiguously showed us): You are full of šit, Prof Weinberg. If you're not satisfied with Me (Nature), just move your aß to a different world. The correct laws of Nature are not deterministic (in the sense of classical physics). They absolutely require the "instrumentalist" attitude to meaningful propositions. They absolutely require one to abandon the classical ideas about a "reality" that is independent of observations. Quantum mechanics is clearly counterintuitive for the laymen – but this doesn't say something about quantum mechanics itself but only about the combination "quantum mechanics and the lay people" – well, mostly about the lay people.

Quantum mechanics doesn't allow any objectively unique single history. Feynman's path integral formulation is one way to see why. It explicitly tells you to sum over all histories, as Hillary described in her Breakthrough video. All intermediate histories in between two observations are equally real or equally unreal. The final state of the trajectories we sum over may be taken to be fixed – because the calculation is answering a specific question, namely what's the probability with the corresponding final state. The initial state of the trajectories we sum over is taken to be fixed because the observer has learned something (e.g. the position of a particle) about the initial state.

As a Pilsen patriot, I am convinced that the beauty of those places of Pilsen is rather objective. ;-) Compare with 2,400 historical pix of Pilsen in a collection of mine.

But the observations are the only way to know something about the state of Nature. Quantum mechanics absolutely prohibits one to say anything about the physical system that is not derived from observations – i.e. that claims to be independent of observers or that is claimed to exist before an observation. There is always some dependence on the choice of the observer in the knowledge and predictions. The observation always influences the observed system and there's no way to reduce this impact to zero.

And so on, and so on. All these claims are absolutely crucial, fundamental postulates of quantum mechanics. Nothing has changed about them since the mid 1920s when quantum mechanics was discovered. And everyone who fails to understand a single postulate in the list is just misunderstanding or misinterpreting the theory – the theory known as quantum mechanics. It doesn't mean that there won't be people who are saying other things. It just means that these people don't have a clue what they're talking about.

And it doesn't mean whether these people say that "they are fine with quantum mechanics". What actually matters is whether they correctly understand it. The people who "have a problem" with quantum mechanics belong to the same basic category as those who say that they are "fine" with quantum mechanics but who misinterpret what it means: They just don't understand quantum mechanics and that's the key problem here. It's absolutely silly to conflate the people who understand quantum mechanics with those who don't (but who also say that they are "fine" with it).

None of these basic principles of quantum mechanics is optional. None of them may be left to your mood or a vote among the laymen or a vote among the pseudointellectuals. None of them depends on the weather. None of them may be selected or refuted by sociologists or philosophers or politicians. They are defining axioms of the theory. If your ideas agree with all the axioms, you are using the theory; if your ideas don't agree with the axioms, you are rejecting quantum mechanics. To disagree with any statement I have made above means to deny the basics of modern physics in the very analogous sense as when one denies the roundness of the Earth, the longevity of life on Earth, or gradual changes of the species as the life forms evolve.

You may also find people who "interpret" Darwin's theory by saying that there was a creator who placed couples from all 40 species on Earth to Noah's Ark and through incest, those produced all animals and humans we see today. But this "interpretation" of Darwin's theory is just rubbish. It's not really an "interpretation" of Darwin's theory. It's a denial of Darwin's theory. Exactly in the same sense, when someone says that there should be an objectively unique (classical) history of the Universe, or the facts about the Universe should be independent of the observer, or... anything in Weinberg's list... then he is simply denying quantum mechanics. He's not "interpreting" anything. He's denying quantum mechanics.

For him to use the word "interpretation" is just a fraudulent sleight-of-hand. It's a lie designed to obfuscate that the person who denies quantum mechanics is exactly as unscientific as the person who prefers creationism over evolution. The term "interpretation of quantum mechanics" was (unfortunately) introduced by Werner Heisenberg himself but he agreed that there was only one correct "interpretation".

There are so many irritating things in the interview and I have touched some of them. But what about this short paragraph?
In any case, Weinberg observed, there’s a danger in evaluating any theory in terms of contemporary philosophical prejudices. Newtonian gravity, Weinberg noted, was itself regarded as unacceptable by many scientists of his era.
It's always risky to evaluate any scientific theory in terms of any philosophical prejudices. But it's even more hopeless to evaluate a 20th century physical theory in terms of 17th, 18th, or 19th century philosophical prejudices – which is exactly what Weinberg is doing. Your philosophical prejudices have nothing to do with the bulk of the 20th century. They've been known to be wrong since 1925. Fifty years ago, you knew that but due to some saddening process, you ceased to know that. Now you can very well watch the video saying "quantum mechanics is oil droplets" and upvote it.

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