By definition, a black hole is a region of spacetime that possesses such an intense gravitational pull, nothing can escape it — not even light. At least that’s how it’s supposed to work. But when you’re a genius physicist by the name of Stephen Hawking, you’re not constrained by such conventional thinking.
On Tuesday, at the Hawking Radiation Conference held at KTH Royal Institute of Technology in Stockholm, Hawking discussed the nature of black holes. Specifically, he talked about what happens to the information of the physical state of an object that gets sucked into a black hole — a contentious issue known as the information paradox among physicists.
Basically, quantum mechanics states that information cannot be destroyed — that the physical state of the object must exist in some capacity. On the other hand, general relativity says the information is destroyed, case closed.
Meanwhile, Hawking decides to come out of nowhere and declare that this information actually never enters the black hole in the first place. “I propose that the information is stored not in the interior of the black hole as one might expect, but on its boundary, the event horizon,” he said at the conference today.
Let’s backtrack. The event horizon refers to a spherical threshold around the black hole. Once an object passes that threshold, it cannot escape. Hawking is basically saying that the physical informantion about an object and its particles get trapped at this region.
The information, he says, gets transformed into a hologram of some sorts — a two-dimensional description of a three-dimensional object. And that hologram stays on the surface of the event horizon. So while an object itself is lost forever in the clutches of a black hole, someone might be able to parse the surface of the event horizon and learn about what went through.
This is important, because if this is true, it’s one step closer to explaining how an object itself could escape a black hole. Hawking is responsible for the concept of Hawking radiation — photons emitted from black holes because of quantum fluctuations. This new theory suggests that Hawking radiation can pick up some of the hologram information sitting on the event horizon as it is emitted outward — and therefore take that information out towards, well, wherever intelligent life can observe it.
All of this comes with a caveat: “The information about ingoing particles is returned, but in a chaotic and useless form,” said Hawking. “This resolves the information paradox. For all practical purposes, the information is lost.” At a public lecture on Monday, Hawking compared this information to a burned encyclopedia: You have the ashes, so all the information is technically there, but you can’t really do shit with ashes.
But again — technically speaking, the information is still there. It exists!
Hawking told the audience: “The message of this lecture is that black holes ain’t as black as they are painted. They are not the eternal prisons they were once thought. Things can get out of a black hole both on the outside and possibly come out in another universe.”
If that’s not the most optimistic thing you’ll read this week, I don’t know what is.