Existence: Am I a hologram?
来源：未知 作者：呼延廓 时间：2019-03-14 08:08:01
By Marcus Chown Read more: “Existence special: Cosmic mysteries, human questions“ TAKE a look around you. The walls, the chair you’re sitting in, your own body – they all seem real and solid. Yet there is a possibility that everything we see in the universe – including you and me – may be nothing more than a hologram. It sounds preposterous, yet there is already some evidence that it may be true, and we could know for sure within a couple of years. If it does turn out to be the case, it would turn our common-sense conception of reality inside out. The idea has a long history, stemming from an apparent paradox posed by Stephen Hawking’s work in the 1970s. He discovered that black holes slowly radiate their mass away. This Hawking radiation appears to carry no information, however, raising the question of what happens to the information that described the original star once the black hole evaporates. It is a cornerstone of physics that information cannot be destroyed. In 1972 Jacob Bekenstein at the Hebrew University of Jerusalem, Israel, showed that the information content of a black hole is proportional to the two-dimensional surface area of its event horizon – the point-of-no-return for in-falling light or matter. Later, string theorists managed to show how the original star’s information could be encoded in tiny lumps and bumps on the event horizon, which would then imprint it on the Hawking radiation departing the black hole. This solved the paradox, but theoretical physicists Leonard Susskind and Gerard ‘t Hooft decided to take the idea a step further: