Black hole paradox remains unexplained

The Takeaway

For physicists, black holes are more than just the stuff of sci-fi adventures, they’re proof that Einstein’s theory of gravity is real.

At least until recently.

Scientists have long debated Einstein’s Theory of Relativity, which helps explain gravity, against the principles of quantum mechanics developed by Stephen Hawking.

“We never understood exactly the details. We’ve had kind of an argument, a logical argument, that this is how things had to work but we never understood the details of how our understanding of space/time had to change,” said Joseph Polchinski, a lead author on the paper.

The phenomenon in question is what happens to a theoretical person when they enter a black hole. Einstein’s theory suggests that the person wouldn’t notice a change until they reached a certain horizon, the end of the line inside a black hole. At that point, the “singularity,” a person would be pulled apart by the immense gravitational force.

But calculations by Polchinski, a physics professor at University of California Santa Barbara, painted a different fate for the theoretical dummy being tossed into a black hole by walking Hawking’s theory backwards and trying to find its breaking point.

“We came to a conclusion that really surprised us because everyone expected that the breakdown would be something very subtle — that you couldn’t really see very easily and we found in fact, that the argument led us to a much more radical breakdown. It is said that if you fall into a black hole, instead of again surviving for awhile and tumbling down the hill into the singularity, you immediately burn up,” Polchinski said. “The cliff, instead of being at the bottom of the hill, has moved out and become, we called it a ‘firewall,’ … a wall of fire right at the event horizon, the point of no return.”

The team spent months vetting its results with friends and double-checking its own work until they eventually became comfortable enough in the correctness of their findings to take them public.

It’s been a year since Polchinski’s discovery, and scientists have yet to come up with an adequate solution to break the paradox. Some are slowly accepting the hypothesis that information can be destroyed, contrary to relativity.

“And that’s great because we have this task of fitting together these two great theories and this is some enormous clue as to what the final picture will look like but we’re in the middle of things, we don’t know where it’s going,” Polchinski said.

Sign up for our daily newsletter

Sign up for The Top of the World, delivered to your inbox every weekday morning.