A black hole is a phenomena from which nothing, not even light, can escape. However, some theories point towards the existence of an “opposite” black hole, into which nothing can enter. Their existence has never been confirmed, and indeed their very nature is a paradox. If nothing can enter a white hole, and everything leaves it, then surely it should not exist? Stephen Hawking argues that black and white holes are one and the same. For now, the possibility of whether they exist remains a mystery.