sciencehabit writes: Physicists have developed a tiny device in which the index of refraction for visible light is zero—so that within it, visible light travels infinitely fast. The gizmo won't lead to instantaneous communication—the famous speed limit of Albert Einstein's theory of relativity remains in force—but it could have a variety of pretty cool uses, including serving as an element in a type of optical circuitry.
I've never been canoeing before, but I imagine there must be just a few
simple heuristics you have to remember...
Yes, don't fall out, and don't hit rocks.