There are getting popularity great Couder's experiments about classical objects having wave-particle duality: oil droplets on vertically vibrating liquid surface - constantly creating periodic waves around. interaction with these ("pilot") waves allows us to observe 'quantum effects':interference pattern in double-slit experiment (particle goes a single trajectory, but it interacts with waves it created - going through all trajectories), tunneling depending on practically random hidden parameters (highly complex state of the field) or orbit quatization condition - that particle has to 'find a resonance' with the field - after single orbit, its internal phase has to return to the initial state.
It's difficult to find good intuition about these experiments from only static pictures - the first time I had occasion to see videos was recent congress on emergent quantum mechanics where Couder had the opening lecture and most of speakers were excited about these experiments. Fortunately I've recently found a youtube video of these experiments:
Some free materials: two-slit experiment paper, Europhysicsnews general paper, slides.
The main qualitative difference with microscopic physics is that while Couder uses external clock, particles should rather have internal one - such understanding of wave-particle duality was started by de Broglie in his doctoral thesis:
that with particle's energy: E = mc^2
comes some internal periodic process: E = hf
It is reminded in very interesting Hestenes paper, in which there is also described recent experimental confirmation of this effect (called e.g. zitterbewegung): http://fqxi.org/data/essay-contest-f..._time_essa.pdf
Such internal periodic motion creates periodic wave-like perturbations of surrounding field - giving localized entity also wave nature ... localized constructions of the field are called soltions, so it suggests to search for particles solitons models, which often have such internal periodic motion, like breathers.
What do you think about these experiments? About such understanding of wave-particle duality?
Have particles both natures simultaneously, or maybe only one of them in one time?
In such case, when and how it is switched? What about Afshar experiment?
update: there has just appeared proceedings (with summarizing article) from mentioned recent Emergent Quantum Mechanics congress in Vienna in which Couder had the opening lecture: http://iopscience.iop.org/1742-6596/361/1
update: good fresh 108 pages presentation http://www.physics.utoronto.ca/~coll...der/Couder.pdf