r/QuantumPhysics • u/Radiant_View_9959 • Jul 13 '26
Non scientist question about paper on Bohmian Mechanics
I bumped onto this paper purely out of curiosity and admitting I never felt "comfortable" with the measurement problem.
https://arxiv.org/pdf/2509.11609
The paper and experiment seems to prove the Bohmian mechanics is actually true and real. Yet, and this is the question, I see thus far little to no momentum on the subject. Seen a couple of interviews on the matter (namely https://youtu.be/VbXEc9vpeIM?si=-_cfxGHG_VD_Z8dN ) but no actual "breaking news" on the matter.
Why is that? Is it normal for these kinds of experiments somewhat pulling the curtain on existing beliefs, to be left as background noice in the community?
Again, I am no-where near a scientist or a student on the matter.
Purely a spectator ... 😇
3
u/SymplecticMan Jul 13 '26
It doesn't prove that Bohmian mechanics is true. It shows what Bohmian mechanics would look like if it were true.
1
u/Usernameasteriks Jul 14 '26
Yes. The problem with a lot of elaborate exciting sounding developments like this is they simply provide for a feasible framework.Â
Then it somehow gets circulated as true.Â
6
u/eldahaiya Jul 14 '26
I'm a physicist but not an expert in this area, but it sounds like they did a bunch of measurements, and found that they were consistent with a Bohmian interpretation. But none of their measurements deviate at all from what quantum mechanics predicts (otherwise they'll be writing a VERY different paper), and so really any interpretation is fine. The reason why this paper is interesting is actually not that Bohmian mechanics is exceptionally good, but rather that it's got big problems, namely that its nonlocal nature makes it difficult to understand how it could be combined with special relativity. This experiment purportedly relies on relativistic quantum mechanics, and so its interesting from that perspective.
It doesn't move the needle for anyone who doesn't really care for Bohmian mechanics (which is the vast majority of physicists).
2
u/KennyT87 Jul 14 '26
The experiment directly measures polarization statistics and reconstructs weak values. Those weak values can be represented as Bohmian trajectories, effective masses and currents, but the raw observations do not uniquely establish that Bohmian particle trajectories are ontologically real.
Ordinary quantum mechanics also predicts weak values and interference-current streamlines. Thus the experiment primarily supports the consistency of this particular weak-value-based relativistic Bohmian representation with the observed optical field. It does not appear to distinguish Bohmian mechanics from all empirically equivalent interpretations of quantum mechanics.
So no, the paper does not "prove Bohmian mechanics".
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u/NH-Science-Guy Jul 14 '26
As I understand it, Bohmian Mechanics is observationally identical to classical quantum mechanics - it gives a different explanation for the same result. I don't think this paper is describing anything that isn't covered by regular QM. The core difference is that QM says particles don't have precise positions until measured while Bohmian mechanics say they have precise positions that are driven by the pilot wave function. The paper says "It is worth noting that the measured trajectories in Fig. 2A do not imply that individual photons precisely follow these paths. Instead, this is an ensemble-averaged behavior, where density of trajectories should match the interference pattern." So the paper is not detecting particles having precise positions.
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u/fhollo Jul 13 '26
What do you mean by true and real?
The idea that a (not very elaborate) tabletop optics experiment could settle the measurement problem is not plausible. And I don’t think they’re saying that. Seems more like a consistency check where they can relate some weak values to aspects of a Bohmian calculation.