Two-slit experiment and "The Truth" I've heard the two-slit experiment described over and over, but there's still something about it that seems unclear to me. When experimenters fire the first, single particle toward the screen, they don't get an interference pattern, do they? The interference pattern shows up only after lots of particles are fired, right? So the interference pattern doesn't indicate that a single particle is a wave that interferes with itself. It just shows that the behavior of large numbers of particles can be described with a wave function. It seems that saying that a single particle goes through both slits and interferes with itself is about the same as saying that a coin flipped once can be both heads and tails, rather than saying that repeated coin-flip results can be described with a wave function. If I'm making any sense at all, could someone please shed some light on my confusion? I really just want to know if we really think that a single particle behaves like a wave that can interfere with itself, and maybe a link to a site that makes it clear to interested laypeople.