Best paper of 2011: Trajectories of quantum particles

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In classical physics, one can always determine specific trajectories of particles, detrimened by Newton's Laws of motion. Not so in quantum mechanics, where one cannot normally speak of specific trajectories because according to the uncertainty principle, any measurement of the position of a particle disturbs the system so that one can not simultaneously measure the momentum and visa versa. However, it seems that by using a concept "weak measurement" one can re-construct the average trajectories of an ensemble of many quantum particles without disturbing any particular one that much. Here is a paper that shows an experiment where the authors attempt to reconstruct average trajectories of single photons in Young's double slit experiment. It's still an ensemble concept but it's probably the closest we will ever get to actually describing trajectories of quantum particles.

Happy new year folks:

http://www.sciencemag.org/content/332/6034/1170.abstract?sid=1acd339e-8cce-4e9f-8572-8ba88292ab00

I would like to read that. Can you advise me on methods of subscription?

ps I am poor( financially).

Here in Denmark on Aarhus university they are currently building a quantum computer with the coldest crystals in the world they made themselves .15 kelvin degrees hot which is -273 degrees celcius.

An "average trajectory" is not a trajectory at all. It is a mathematical construct.

ruveyn

I have failed to access the paper.

Hopefully I will have more fortune with 2012.

Sorry about that. I think that you can purchase the article without subscribing. Just click on "read full text" underneath the abstract and you'll see that as an option.

Yes, it only works on ensembles of large numbers of particles. However those average trajectories successfully reproduce the interference pattern in Young's double slit experiment and they also follow the single-particle trajectories predicted by the Bohm-de Broglie interpretation of quantum mechanics (although the result itself is independent of the interpretation). If you read the article, it's actually quite fascinating.

Rather expensive to read. Do you know any freebies.

ruveyn

Unfortunately, I couldn't find any preprints and that particular journal seems rather fussy. However, I do have my own copy and I found this preprint of a different paper by three other authors who reexamined their data and ultimately confirmed their conclusions:

http://arxiv.org/abs/1109.4436