Now Dr. Bee has posted a more detailed criticism of the theory.
One of the big disadvantages of Bohmian mechanics, that Einstein in particular disliked, is that it is even more non-local than quantum mechanics already is. That’s because the guiding field depends on all the particles you want to measure. This means, if you have a system of entangled particles, then the guiding equation says the velocity of one particle depends on the velocity of the other particles, regardless of how far away they are from each other. ...This is an important point.
[Reader:] The argument against Bohmian mechanics is that it is non-local, and QFT requires locality. But didn't Bell prove that the universe is non-local (for most physicists at least; I realize you have an alternative explanation for his results)?
[Sabine Hossenfelder:] First, you cannot use a mathematical theorem to prove how the universe is. What Bell proved is that theories of a certain type obey an inequality. Experiment shows that this inequality is violated. It follows that one of the assumptions of Bell's theorem must be violated.
A violation of one of these assumptions is qua definition what people in quantum foundations call "non-locality". It is an extremely misleading use of the word and has nothing to do with that particle physicists call "non-locality" which refers to non-local interactions.
These two different types of non-locality have caused so much confusion I really think we should stop referring to quantum mechanics as "non-local". Some have suggested to instead use the term "non-separable" which makes much more sense indeed.
In any case, Bohmian mechanics violates Bell's inequality and is thus non-local in Bell's sense. This is fine and not the problem I was talking about. The problem is that the ontology of Bohmian mechanics is non-local in the QFT sense (as I explained in the video). This is not necessarily a problem, but certainly one of the reasons why it's been hard to make a QFT out of it. The other problem is Lorenz-invariance (which I refer to as the "speed of light limit).
Bell nonlocality is an abuse of terminology that only confuses people. Bohm's theory is truly nonlocal in a way that no scientific theory is. It is a fringe theory that no one has found useful for anything.
Sometimes someone claims that Bohm's theory is more intuitive, but that is nonsense. The nonlocality makes it more counter-intuitive than any other textbook theory.
When she said the "historical context is relevant", I thought that she was going to tell us that Bohm was a Commie. It is funny how he has a cult following. There is some weird ideology driving support for his theory, but even after watching the movie, I cannot figure out what it is.
Bohm's theory is convinient for quantum cosmology, since it avoids the problem of the system and the observer which are necessary in the Copenhagen interpretation so that the Copenhagen interpretation cannot be applied to the whole universe.The theory is nonlocal, so events in one galaxy can depend on subtleties in another galaxy. And that is supposed to be convenient for cosmology? I doubt that it has ever been of any use to cosmology.