The Experiment That Breaks RelativityA tipoff is when it says that all the textbooks are wrong:Veritasium 19.7M subscribers
Dec 18, 2025
How an argument between Einstein and Bohr changed quantum mechanics forever.
7:09 - Physicists tell a version of this story, you know that you will find in physics textbooks 7:15 and in pop science books and that you know physicists tell amongst ourselves that 7:20 what happened was Einstein and Bohr had a great debate and Einstein was unhappy with quantum mechanics ...No, the quantum mechanics textbooks are right, and this video is wrong.33:29 - We did do this experiment again, and the number, we got very much agreed with quantum mechanics, 33:41 but this is one of the most misunderstood experiments in all of physics. - You'll find in all sorts of physics textbooks and papers 33:48 and whatnot, that what Bell's theorem proves that it rules out local hidden variables or local realism. ...
35:00 it's a really deep misunderstanding that shows up in almost every single textbook on the subject. - So what does Bell's theorem really prove?
Here is the textbook explanation of quantum mechanics.
Position and momentum do not commute, and do not have definite values until observed. There is a Heisenberg uncertainty. If you measure both, your answers will depend on the order of measurement.
This contrasts with classical mechanics, where these variables have values independent of measurement.
Einstein and Bell wondered if maybe quantum mechanics could be reformulated as a classical theory. Bell cleverly formalized classical theories as theories of local hidden variables, and proved a theorem that such theories differ from quantum mechanics. Experiments then confirmed the quantum mechanics that everyone believed since 1930.
That was the end of the matter, for all serious thinkers. But some pursue some loopholes to this argument. Namely nonlocal theories, many-worlds, and superdeterminism.
Where Veratasium goes off the rails to make three fundamental errors.
(1) That simple entanglement examples show that quantum mechanics is nonlocal. The given example is to produce two related particles, such that a conservation law tells you that observing one immediately tells you something about the other.
The same thing happens in classical mechanics. This does not distinguish classical and quantum theories, or local and nonlocal theories.
(2) That "realism" means a classical theory, so if you believe in reality, you have to accept classical mechanics and reject quantum mechanics.
Quantum mechanics is not a classical theory. If you define realism that way, then quantum mechanics does not obey local realism. In particular, position and momentum do not have values until observed.
(3) That many-worlds theory somehow provides a way out of the quantum puzzles of locality and realism.
No, many-worlds theory does not, and cannot, explain anything.
John Bell passed away suddenly at the age of 62. 40:05 He didn't know it, but he had been nominated for the Nobel Prize just a year earlier - In a talk he gave in Geneva in January, 1990. 40:14 He said, I think you're stuck with the non-locality. I don't know any conception of locality, which works 40:22 with quantum mechanics. That was eight months before he died.Yes, some believed that Bell deserved a Nobel for this, but the mainstream view, and the Nobel view, is that Bell was wrong. The 2022 prize was given for some Bell-related work, but the prize citation pointedly avoided giving Bell any credit for his goofy non-locality ideas.
My title refers to this movie clip.
This video is very disappointing. The channel had been very reliable and informative. I have learned a lot. But when you see a video claiming that all the textbooks and top experts are wrong, you probably should not believe it.
In this case, the video is rejecting mainstream physics that has been well-accepted for a century. And it is for the pursuit of goofy ideas that cannot lead anywhere.
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