experiment he’d carried out three years earlier at the Institute for Radiation-Induced Mass Studies, a privately funded research center in Boston. As Afshar explained, it’s in part due to the physics community’s incredulous response to the experiment that he is now taking a detour into acousto-haptics.
The experiment was a variation on the famous double-slit experiment familiar to any freshman physics student. Light passing through a pair of pinholes in a screen forms an interference pattern that’s most easily explained by thinking of light as a wave. Quantum mechanics, however, says that light travels in packets called photons.
In the classic double-slit experiment, if you try to measure which slit a particular photon passed through in the experiment, the interference pattern disappears; the upshot of this “principle of complementarity,” first defined by Bohr in the 1920s, seems to be that experimenters can measure the wave-like properties of light or the particle-like properties, but not both at the same time. Afshar’s test upset this conventional notion. By inserting a lens and an array of vertical wires into the double-slit apparatus, he says he was able to detect individual photons and wave patterns simultaneously. (For the details see this New Scientist article; subscription required.)
No less a thinker than Albert Einstein was doubtful about Bohr’s complementarity principle, but it’s become the accepted dogma in physics over the past 70 years, and Afshar’s results have met with widespread resistance. Afshar says he was prepared for this. “When you do an experiment that you know is going to change the very foundations of what everybody believes, you have to have a long-term plan—that is the reality of the world of science,” Afshar says. “Every time somebody does something like this they should expect at least five to ten years of complete isolation.”
Afshar’s isolation has not been quite complete: he has a position as a visiting research professor in the department of physics and astronomy at Rowan University in Glassboro, NJ. But he says he’s ready to wait for up to a decade on the outskirts of academia while the physics community assimilates his paradigm-busting research results, and while he cogitates about a new, even more convincing experiment. And he says that it was his stay in university housing at Rowan a couple of years ago—in the same dorm with video game-addicted undergraduates—that gave him the idea for a project to fill the gap.
“I don’t want to embarrass the kids there—I think they are typical of college kids all over the place—but I would from time to time tell them that they shouldn’t be playing their video games so loud,” says Afshar. “You could feel the whole place shaking. After harassing these kids a bunch of times, I realized, first of all, that my nagging was ineffective, and secondly, that there was something missing [from standard video game setups]. They really needed this pumping bass sound. So I said, instead of bothering everybody, why don’t I think about how to deliver the same experience on an individual level without having to make everything shake.”
Afshar says he spent the next two years studying the neuroscience and ergonomics of what might be called extra-auditory tactile perception—the way the brain uses information about vibrations below the level of sound to supplement its picture of the environment. Unlike visual information, which the eyes feed directly to the cortex, tactile information flows first to
