When Light and Atoms Share a Common Vibe
An especially counter-intuitive feature of quantum mechanics is that a single event can exist in a state of superposition — happening both here and there, or both today and tomorrow.
Such superpositions are hard to create, as they are destroyed if any kind of information about the place and time of the event leaks into the surrounding — and even if nobody actually records this information. But when superpositions do occur, they lead to observations that are very different from that of classical physics, questioning down to our very understanding of space and time.