How is this possible? It’s like the Universe itself doesn’t understand our idea of “nothing” at all; if we were to remove all the quanta of energy from our Universe, leaving behind only empty space, we would immediately expect that the Universe would be at absolute zero: with no energetic particles anywhere to be found. Yet that’s not the case at all. No matter how “empty” we artificially make the expanding Universe, the fact that it’s expanding would still spontaneously and unavoidably generate radiation. Even arbitrarily far into the future, or all the way back before the hot Big Bang, the Universe would never truly be empty. Here’s the science of why.
Mandarin in an Empty apartment
I hold a mandarin in my hand So small that it fits in my palm I could crush it and destroy the entire universe…