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Photo First: Light Captured As Both Particle and Wave
mpicpp sends word that scientists have succeeded in capturing the first-ever snapshot of the dual behavior of light. "It's one of those enduring Zen koans of science that we've all grown up with: Light behaves as both a particle and a wave—at the same time. Einstein taught us that, so we're all generally on board, but to actually understand what it means would require several Ph.D.s and a thorough understanding of quantum physics. What's more, scientists have never been able to devise an experiment that documents light behaving as both a wave and a particle simultaneously. Until now. That's the contention of a team of Swiss and American researchers, who say they've succeeded in capturing the first-ever snapshot of light's dual behavior. Using an advanced electron microscope – one of only two on the planet – at the EPFL labs in Switzerland, the team has generated a kind of quantum photograph of light behaving as both a particle and a wave. The experiment involves firing laser light at a microscopic metallic nanowire, causing light to travel — as a wave — back and forth along the wire. When waves traveling in opposite directions meet, they form a "standing wave" that emits light itself — as particles. By shooting a stream of electrons close to the nanowire, the researchers were able to capture an image that simultaneously demonstrates both the wave-nature and particle-nature of light. 'This experiment demonstrates that, for the first time ever, we can film quantum mechanics — and its paradoxical nature — directly,' says lead researcher Fabrizio Carbone of EPFL, on the lab's project page. The study is to be officially published this week in the journal Nature Communications."
Light behaves as both a particle and a wave—at the same time. Einstein taught us that, so we're all generally on board, but to actually understand what it means would require several Ph.D.s and a thorough understanding of quantum physics
Stop pretending physics is spooooky. It's not that difficult to understand, at least at a superficial level. And I don't have a degree, let a lone a Ph.D, but even I can explain it (again, superficially):
Time dilation means that the faster you go, the slower time goes. If you're travelling at the speed of light in a vacuum, then the speed at which you're travelling through time is slowed infinitely. This means a photon experiences no passing of time between the moment it is created, and the moment it collides with something.
But the speed of light is finite, so it has to travel through time to go between two points. But because from the photon's perspective it's travel is instantaneous, it can't experience that time. So a photon doesn't know where it's going to land, until it does. And so until it does land, it could have landed anywhere. So when a photon is created, it travels out in all directions, like a wave, until it lands somewhere and the wave collapses.
The part that's hard to understand is the why.
The brick is also a wave, it's just such a complex wave that it would be nearly impossible to express in those terms (it's just a sum of all its subatomic parts, after all). If we could express a brick in terms of a wave, the values would just be endless strings of numbers that make little sense to our human brains. Then, lets say we devise a way to visualize those values in a form more palatable for human consumption; you'd end up with a picture of a brick.