'The latest edition of New Scientist has a fascinating article titled
“Quantum shadows: The mystery of matter deepens” by Anil Ananthaswamy (requires free registration to read). It discusses recent experiments conducted to try (yet again) to determine why photons sometimes appear as particles and sometimes appear as waves (the famous
“double slit” experiment).
In this latest experiment, researchers have removed the human interference in deciding whether or not the system is “open” or “closed”. Without trying to explain the science (because it’s way over my head), the results are fascinating. Essentially the article suggests that photons (and, by extension, all other sub-atomic particles) are NEITHER particles NOR waves. Instead, the concepts of “particles” and “waves” are ideas that we are placing on quantum particles because our brains aren’t able to understand what is truly going on. Here’s Anil’s conclusion:
It’s a notion that takes us straight back into Plato’s cave, says Ionicioiu. In the ancient Greek philosopher’s allegory, prisoners shackled in a cave see only shadows of objects cast onto a cave wall, never the object itself. A cylinder, for example, might be seen as a rectangle or a circle, or anything in between. Something similar is happening with the basic building blocks of reality. “Sometimes the photon looks like a wave, sometimes like a particle, or like anything in between,” says Ionicioiu. In reality, though, it is none of these things. What it is, though, we do not have the words or the concepts to express.'
physics | The Three Illusions