Monday, 17 September 2007

Afshar experiment

Slowly, so slowly, the work on the book In the Country of the Blindfolded continues. I started to write a section devoted to the Afshar experiment. When it surfaced three years ago, thanks to Mark Chown article in the New Scientist titled Quantum rebel, the reaction was overwhelmingly negative. Quite a lot of people set out to prove where and why Afshar was wrong in his analysis. This February, another piece by Mark Chown, in the same New Scientist is titled Quantum rebel wins over doubters. So, something is brewing...

I have not formed my opinion yet. But perhaps there is someone among the readers who has interesting ideas, suggestions of `must read' papers etc?

1 comment:

Xawer said...

Ex-experimentalist's comments, based on one-and-half-hour analysis of the problem, common sense, and strong affection towards Copenhagen, and even stronger affection towards Lower Austria.

"New Scientist" gives for free only tabloid-type banner: "IT ROCKED quantum theory", but quite a little more. Maybe, they could give something if I pay $4.95. However, my common sense directs me toward spending those €4 for one more bottle of Gumpoldskirchener Rotgipfler(*) rather than to read remaining 781 words by M.Chown.

Ad meritum: comments based of _MY_ understading of Afshar experiment:

1. The experiment did not show anything contrary to quantum-mechanics and other physics theories, established by early XX century.

2. The experiment (once again) shows that the distribution of single photons behaves exactly the same like Maxwellian waves. It is the 10'th, (or maybe 100'th? 1000'th?) experiment 'demonstrating' the violation of classic/quatnum theory, by showing that single photons diffract like waves but interacts with detectors like billard-ball-like particles.

3. The experiment DID NOT show that photons behave like billard balls at any of aspects, which could be contrary to wave view.

4. Afshar seems to be yet another guy claiming that [light/photons] go along the path 'A' (which is prooved in a configuration where no other path is possible) and then showing (in config of multiple paths available) that the experimental results are inconsistent with 'path A - path B' model.

So - I remain comfortable at Copehagen, I ride a bike, I eat meatballs and really like fried flander(**).


For non-Europeans:
(*) That's the best time for Austrian wines! They just sell out 2006 vintage before 2007'th would come out.
(**) flunder/flander/flądra/flindras is a fish, similar to sola or flatfish, but found only in Baltic Sea.