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A more critical paper came out yesterday hi-liting some of the differences between QM, Bohmian mechanics and bouncing droplet analogues:
http://arxiv.org/pdf/1410.1373.pdf
On the analogy of quantum wave-particle duality with bouncing dropletsWhile Bohmian quantum mechanics exhibits nonlocal features , the evolution of the droplet and the surface waves is rooted in hydrodynamics which is manifestly a local theory, unless incompressibility is assumed.
In the de Broglie-Bohm interpretation, the specific trajectory of the quantum particle does not backact onto the evolution of the wavefunction, whereas the droplet creates new surface waves at the position where it bounces. Those surface waves do evolve, to a very good approximation, according to a linear theory, but a direct mapping to the Schrodinger equation is not obvious...More importantly, however, the probability of finding a droplet in the minima never reaches zero as it does for a particle in the quantum case.
Here we note a striking contrast between the trajectories in the bouncing droplet system and those resulting from Bohmian mechanics. One of the tenants of Bohmian trajectories is that the trajectories are forbidden to cross each other, and in the double-slit experiment the trajectories from each slit will not cross the center line, but it is obvious that the trajectories in Fig. 5(d) have no such reluctance to do so.
With increasing which path information the probability density becomes more dependent on a single slit. Consequently the observed interference pattern becomes less pronounced as it is the wave function arising from both slits that gives rise to the pattern. We can make an analogy in the bouncing droplet system with the memory parameter being analogous to the which path information...The visibility will increase with increasing memory but never reach one, in contrast to quantum particles with a which path information of zero.
In view of this, it is not obvious to what extent the present classical analogy of quantum wave-particle duality can be maintained in more complex situations involving, e.g., more than one droplet.
http://arxiv.org/pdf/1410.1373.pdf