The Bohmian model is that particle positions are an intrinsic part of the evolution of the theory. This is in contrast to, say, the Copenhagen interpretation i

The Bohmian model is that particle positions are an intrinsic part of the evolution of the theory. This is in contrast to, say, the Copenhagen interpretation in which the particle position is not a part of the evolution of the system. In the CI, wave functions are real (I guess) and we need something external to the model, called measurements, which mathematically do some complicated operation to the wave function of putting it in an approximate eigenstate (it can't do it exactly nor is the approximate nature specified and the timing of this is generally specified but not really clear about time of arrival measurements in scattering experiments). In the Bohmian model world, particle positions would be real. They may not be measurable to the inhabitants to infinite precision (assuming quantum equilibrium, i.e., the particles are distributed according to psi-squared), but the particles have definite postions in this world. It has in it no need to postulate anything about measurement. Observables and all that are deduced from the theory. It is important to ask what in a model has a fundamental existence, what has an implied existence, and what is just a useful term for something secondary to all that. In Bohmian mechanics, particles (things with position) have a fundamental existence, the wave function has an implied existence because that is how the particles move about, and spin has a secondary existence since it does not have a separate existence from either of those two objects, being solely deduced from the motion of the particles. The Bohmian model is well-defined and has an easy correspondence between the entities that are real and our experience (stuff has position). It does not require observers to be complete. A Bohmian world could happily exist without PhDs, humans, mammals, life forms, etc. What's real in CI? Not really sure, but I guess the wave function and measuring devices? It does require something that corresponds to measurements and the evolution of that classical world is distinct and separate. This is the context of calling BM a realist theory. I would just call it an actual theory. Bohmian mechanics illuminates the quantum randomness, allowing it to be analyzed. The theory happens to be deterministic (ignoring creation/annihilation), but it derives the apparent randomness from all that and it clarifies the meaning of psi-square.