Friday, July 23, 2004
( 11:36 AM )
All the political news is so boring compared to the announcement from Stephen Hawking (the most brilliant human on earth)yesterday that he may have been completely wrong about black holes. Now, putting aside an intelligent man who is able to actually search for more answers even when it puts his original conclusion to the test, and then even to admit he was wrong when he comes to a new conclusion, this is the sort of announcement that just makes this Mama thrill with thoughts about the vastness of space.
So Dr. Hawking admitted publicly at a conference yesterday that he was conceding a bet he made with other physicists about what a black hole can do. Basically, Dr. Hawking thought that if something was sucked into a black hole, it was destroyed and lost forever. But others thought that information could come back out after being sucked in. Now, Dr. Hawking is agreeing.
This esoteric sounding debate is of great consequence to science, because if Dr. Hawking had been right, it would have violated a basic tenet of modern physics: that it is always possible to reverse time, run the proverbial film backward and reconstruct what happened in, say, the collision of two cars or the collapse of a dead star into a black hole.
Now, on the basis of a new calculation, Dr. Hawking has concluded that physics is safe and information can escape from a black hole. "I want to report that I think that I have solved a major problem in theoretical physics," he told his colleagues, according to a transcript of his remarks.
Theorists have worried about the fate of information in black holes since the 1960's. In 1974, Dr. Hawking stunned the world by showing that when the paradoxical quantum laws that describe subatomic behavior were taken into account, black holes should leak and eventually explode in a shower of particles and radiation.
The work was, and remains, hailed as a breakthrough in understanding the connection between gravity and quantum mechanics, the large and the small in the universe.
In his new calculation, Dr. Hawking said that because of quantum uncertainty, one could never be sure from a distance that a black hole had really formed. There is no way to discriminate between a real black hole and an apparent one.
In the latter case an event horizon, the putative point of last return, could appear to form and then unravel; in that case the so-called Hawking radiation that came back out would not be completely random but would have subtle correlations and thus could carry information about what was inside.
According to quantum theory, both possibilities - a real black hole and an apparent one - coexist and contribute to the final answer. The contribution of the no-black-hole possibilities is great enough to suffice to allow information to escape, Dr. Hawking argued.
Another consequence of his new calculations, Dr. Hawking said, is that there is no baby universe branching off from our own inside the black hole, as some theorists, including himself, have speculated.
So quantum physics is rescued. Of course the scientists will continue to debate, and some aren't yet willing to concede Hawking's new position. But the idea that information can escape a black hole seems to confirm recent experiments in string theory - where scientists are trying to come to a Theory of Everything to explain all the forces of nature together.
Crazy quantum physicists. Yet very, very cool.