Here's Neil DeGrasse Tyson explaining it some more:
So what's the big deal? Putting it into the most basic possible terms: We've observed small particles in the universe that act like they're "talking to each other" and determining how to be, even after they're separated and shouldn't be able to affect each other. It's like we can slice a red apple in half, put each half in a box and send the two boxes to opposite sides of the world, then have somebody open one box and paint their half of the apple green, and then when somebody on the other side of the world opens the box with their half-apple in it, it's turned green too. And we don't know how this works. We've been trying to find out since the time of Einstein. Einstein himself called this "a spooky action at a distance." Not only are we observing the effect that two particles can have on each other, and not only is it instantaneous (defying everything we know about the speed of information alone), but it appears to even be possible to have the same thing happen when the entangled elements are separated not only by space, but time as well. So Israeli scientists have made photons affect each other even when they didn't coexist at the same time. So either we're dead wrong about this, or we have a way to both time travel and teleport either information or physical actions instantly. It could be a flaw in our reasoning based on some fundamental shortcoming of human perception and reasoning. A LiveScience infographic:
And finally, quantum entanglement has been simulated within the world of, of all things, Minecraft.
Are we nuts? Maybe. Maybe the universe is nuts, too.
