Physics Rebel Aims To Shake Up the Video Game World

waderoush writes "Physicist Shahriar Afshar is famous as the designer of the 'Afshar Experiment,' a study first described in 2004 that called into question Neils Bohr's observation that it's impossible to observe light's wave-like properties and its particle-like properties at the same time. Not surprisingly, the idea met with widespread resistance in the physics community. While he waits for the controversy to settle down, Afshar himself is taking a detour into the video game world. He's now the president and CTO of Immerz, a Cambridge, MA-based startup building an 'acousto-haptic' interface that drapes over a gamer's shoulders and turns video game sound into (literally) chest-pounding vibrations. Xconomy was allowed to test the device, and has the full story behind Afshar's unusual journey and the company's hopes for enhancing PC and console gamers' experience of action/adventure/first-person-shooter titles."

Comments

For a physics rebel

[sleeponthemic]

This is fairly tame. I remember picking up a full aura bass cushion set for about $5 from a retailer, after they tanked. Geographically locating it on the shoulders isn't going to save it from being a bit of novelty nonsense.

Re:Sounds dangerous

[MRe_nl]

Reminds me of the "Get ready to Rumble"-pack, but with a chip on my shoulder.
http://en.wikipedia.org/wiki/Rumble_Pak

Re:Physics rebel?

[radtea]

If Afshar's theory/experiment contradicts the mainstream physics

The funny thing is that it doesn't even do that: it is an attempt to find an experiment that distinguishes between different interpretations of QM, which no one has ever been able to do. Everyone agrees, phenomenologically, what the results of the experiment should be, and the results of the experiment are consistent with the results predicted by QM.

The question that got people arguing is whether or not this proves or disproves the Copenhagen Interpretation. My own view is that since the Copenhagen Interpretation is barely coherent (pun intended) it is very hard to "disprove". And the very fact that physicists have got along with Copenhagen for decades shows how little interpretation matters when it comes to QM: any old thing will do, so long as it provides a reasonable guide to calculation.

Because Copenhagen insists that we only compute things in the context of the experiments actually being performed, it does this quite well. This has practical implications when taking integrals in calculations of angular correlations in gamma-ray spectroscopy, for example: you integrate over the things you aren't measuring because Copenhagen tells you they have no objective meaning. I'm sure other interpretations could do the same thing, but there is no experimental basis to choose between them, so it's just a parlor game to talk about them.

A bit of background on duality

[Interoperable]

For those who care: some background. The experiment discusses the "duality of light" (light/particle nature). However, the question isn't "does light behave as a wave or a particle?" That's not really a question that needs asking, various theories of the propagation of light are well established and understood. Geometric optics treats light as a particle and is valid within the constraint that you're dealing with structures that are large compared with the wavelength of the light. The electromagnetic wave approach covers, more or less, all propagation of light and treats light as a wave. Finally, quantum optics is used to explore the interaction of light with matter. Here's where duality becomes interesting: working with the electromagnetic field as a quantum field, the notion of a photon as a quantum particle arises. The propagation of the photon is well described by considering it as a classical electromagnetic wave but the picture of a photon is useful when discussing it's interaction with matter (for example, the photoelectric effect).

In the case of the double-slit experiment, which is the basis for Afshar's experiment, the propagation of light can be described classically by treating it as an electromagnetic wave. However, double slit experiments work with single photons as well. Single photons are only described by quantum optics and when the experiment is done with prepared single photons, the interference fringes (viewed in the Fourier plane) can be considered a measurement of the momentum of the photon as it passes through one of the slits (where it ends up on the screen depends on what direction it was travelling in when it passed through the slit). Which slit it passes through is a measurement of the position. Position and momentum are complementary variables in quantum mechanics and cannot be measured simultaneously with perfect accuracy.

Afshar proposed an experiment to do exactly that, measure both. The key criticism, however, is that the interference fringes (momentum measurement) aren't observed, they're inferred, which doesn't really constitute a measurement. His thought experiment was analyzed quantitatively as well as was found not to violate the complementarity of the position and momentum variables. The issue is further obscured by the fact that the measurements are related to the spatial mode of the photon and it's propagation vector, which is related, but not quite identical, to a position-momentum measurement for a more classical particle. In any case, Afshar's work is interesting, but doesn't really tread the revolutionary/crackpot line, it can be analyzed well within the existing body of knowledge of quantum optics.