It would be tiresome to go through all the proposals listed in that article, identifying how they work, the resultant limitations, and then speculating whether they might nonetheless help us understand reality one day. Or at least, I think I would save that kind of analytical effort, for an audience of physicists interested in ontology.
But let me just discuss one example. The proposal discussed in the most detail, is due to Dürr et al. The article straight out says that they rely on the existence of a “preferred foliation” of spacetime. That means that to define their “relativistic” Bohmian mechanics, they still need a particular decomposition of spacetime into a stack of spacelike hypersurfaces. Their trick is to then say, well, we don’t need to use a coordinate system in which those hypersurfaces are all “t = constant”. We can do a relativistic boost, and switch to a new coordinate system with a new time coordinate, in which those hypersurfaces are tilted with respect to the time axis.
That’s formally true, but nonetheless, their pilot wave and their equations of motion are only defined with respect to one specific foliation, which de facto defines a notion of absolute simultaneity.
The point is that all these “extensions to relativity” involve some kind of trick, or they only work in an artificially narrow setting, or they meander off in some eccentric direction. There is certainly no relativisitc Bohmian mechanics known, that can deal with all the known phenomena of field theory, like pair creation and gauge invariance.
It would be tiresome to go through all the proposals listed in that article, identifying how they work, the resultant limitations, and then speculating whether they might nonetheless help us understand reality one day. Or at least, I think I would save that kind of analytical effort, for an audience of physicists interested in ontology.
But let me just discuss one example. The proposal discussed in the most detail, is due to Dürr et al. The article straight out says that they rely on the existence of a “preferred foliation” of spacetime. That means that to define their “relativistic” Bohmian mechanics, they still need a particular decomposition of spacetime into a stack of spacelike hypersurfaces. Their trick is to then say, well, we don’t need to use a coordinate system in which those hypersurfaces are all “t = constant”. We can do a relativistic boost, and switch to a new coordinate system with a new time coordinate, in which those hypersurfaces are tilted with respect to the time axis.
That’s formally true, but nonetheless, their pilot wave and their equations of motion are only defined with respect to one specific foliation, which de facto defines a notion of absolute simultaneity.
The point is that all these “extensions to relativity” involve some kind of trick, or they only work in an artificially narrow setting, or they meander off in some eccentric direction. There is certainly no relativisitc Bohmian mechanics known, that can deal with all the known phenomena of field theory, like pair creation and gauge invariance.