subtlefuge said:
If everyone in the world was sleeping at the same time, would the universe cease to exist?
Good question; allow me to take it too far.
If the universe exists, it only exists for the period of time that it is being observed in, according to quantum mechanics. Any observation made about the state of the universe would collapse the wavefunction of the universe itself. If the universe is in a state of being unobserved by everyone, then it is a superposition of all possible states, existing or not existing. This state of the universe being an uncollapsed wavefunction is only resolved when an observer wakes up and observes the universe, causing the wavefunction to collapse and form a
one universe. It's sort of like blowing up the Schrödinger's cat experiment to the size of the universe, with the living cat representing our existing universe, and the dead cat being our universe ceasing to exist. "What's a wavefunction?" I hear you ask. The short answer: it's a probability
thing .
So in answer to your to your question: yes and no at the same time, so therefore possibly maybe? Whatever, just make sure that someone is keeping an eye on the universe when you go to sleep, or else who knows what might happen.