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gentzen said:At least for Bohmian mechanics

I once conjectured that Bohmian mechanics arrived at an unfortunate point in time, when interest in QFT overshadowed potential opportunities offered by Bohmian mechanics:PeterDonis said:Which is notQFT. It is either an interpretation of non-relativistic QM, or (in its more ambitious formulations) an attempt to extend that interpretation into an actual competing theory, which, however, is stillnon-relativistic, and is thereforeconsidered a non-starter by most physicists(though not all--at least one PF regular, @Demystifier, has published papers defending the view that Lorentz invariance is only an emergent symmetry and that we will end up finding that there is an underlying theory that works more like non-relativistic Bohmian mechanics).

When David Bohm proposed his new interpretation in 1952, the term "Copenhagen interpretation" didn't exist yet, he had to talk of the "usual physical interpretation of quantum theory" instead.

...

So the historical context is that the divergence problems of the quantum electrodynamics theory from Dirac, Pauli, and Heisenberg had been solved by Schwinger, Feynman and others in 1949 by renormalization. The predictive power was excellent, but interpretation remained elusive. And suddenly modifications, reformulations and reinterpretations of normal quantum mechanics started to proliferate, attacking normal quantum mechanics while remaining silent about quantum field theories.

- One of those opportunities was the analysis of non-locality, later done by Bell, and the reason why I brought up Bohmian mechanics in the other thread.
- Another "opportunity" from my point of view would have been an analysis of "how and why" Bohmian mechanics breaks invariance under (linear) canonical transformations. I still hope to learn more about this from Peter Holland's "Hamiltonian theory of wave and particle in quantum mechanics I. Liouville’s theorem and the interpretation of the de Broglie-Bohm theory" and "Hamiltonian theory of wave and particle in quantum mechanics II: Hamilton-Jacobi theory and particle back-reaction" (2001). I somehow blame Wolfgang Pauli for missing that analysis, because he was an expert for such invariances, shoot down de Broglie's initial proposal, and ignored (and ridiculed) Bohm's requests for feedback.
- In a certain sense, non-locality was Einstein's topic, and invariance was Pauli's topic. So I wonder whether Bohmian mechanics also contains "missed opportunities for analysis" of topics close to Heisenberg or Bohr. For Heisenberg, I have an idea for one such topic: Heisenberg justified the need for interaction between classical mechanics and (non-relativistic) quantum mechanics via measurement as some sort of boundary condition for open systems. His interpretation seems to allow ("classical") reactions or control based on measurement outcomes, while for Bohmian mechanics it is at least unclear whether such "classical" interaction based control is possible too, in case where Bohmian mechanics is only used to provide boundary conditions (i.e. not used in the MWI sense as a closed model of the entire universe).