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"The near-death experience story is so common that it has become a bit of a cliché: A medical patient, hanging in a murky limbo between life and death, is drawn through a tunnel of bright light, meets their maker, and is told they must return to the land of living."

What happens when you throw an elephant into a black hole? It sounds like a bad joke, but it's a question that has been weighing heavily on Leonard Susskind's mind. Susskind, a physicist at Stanford University in California, has been trying to save that elephant for decades. He has finally found a way to do it, but the consequences shake the foundations of what we thought we knew about space and time. If his calculations are correct, the elephant must be in more than one place at the same time. In everyday life, of course, locality is a given. You're over there, I'm over here; neither of us is anywhere else. Even in Einstein's theory of relativity, where distances and timescales can change depending on an observer's reference frame, an object's location in space-time is precisely defined. What Susskind is saying, however, is that locality in this classical sense is a myth. Nothing is what, or rather, where it seems. This is more than just a mind-bending curiosity. It tells us something new about the fundamental workings of the universe. Strange as it may sound, the fate of an elephant in a black hole has deep implications for a "theory of everything" called quantum gravity, which strives to unify quantum mechanics and general relativity, the twin pillars of modern physics. Because of their enormous gravity and other unique properties, black holes have been fertile ground for researchers developing these ideas. It all began in the mid-1970s, when Stephen Hawking of the University of Cambridge showed theoretically that black holes are not truly black, but emit radiation. In fact they evaporate very slowly, disappearing over many billions of years. This "Hawking radiation" comes from quantum phenomena taking place just outside the event horizon, the gravitational point of no return. But, Hawking asked, if a black hole eventually disappears, what happens to all the stuff inside? It can either leak back into the universe along with the radiation, which would seem to r