Dinosaur
05-09-03, 09:38 PM
A special edition of Scientific American appeared on news stands 3-6 weeks ago: The Edge of Physics. Most of the people who post here should be interested.
I was fascinated by the article about loss of information in Black Holes. To me, Hawking has the right idea, and I am amazed that anybody disagrees. He says something like the following.
When a deck of cards is scattered, a book is burned, or in other circumstances, information seems to be lost. In a practical sense, it is lost. However, in principle, all the quantum level processes involved are reversible. If we know the exact details (big if) of what happened, the processes can be reversed and the information retrieved. Both classical and quantum theory claim that micro reversibility is valid and provides for preservation of information (in principle). In 1976 I (Hawking) showed that black holes violate the principle of micro reversibility and result in the loss of information.Some other experts in theoretical physics claim otherwise, making statements like the following.
Hawking is wrong. You cannot undermine micro reversibility without destroying energy conservation. If Hawking is correct, the universe would heat up to some far out temperature. Since we do not observe the temperature increase, black holes cannot cause information loss. There must be some way to retrieve the information. Has anybody here read the article? Does anybody have some ideas on this?
Unfortunately, the article does not provide much proof or argument in favor of either point of view. I doubt if I could understand the arguments if they were presented.
Agreeing with Hawking (as I do), cannot be stupid, but I do not feel comfortable dismissing the other side without understanding how they arrived at their opinion.
I was fascinated by the article about loss of information in Black Holes. To me, Hawking has the right idea, and I am amazed that anybody disagrees. He says something like the following.
When a deck of cards is scattered, a book is burned, or in other circumstances, information seems to be lost. In a practical sense, it is lost. However, in principle, all the quantum level processes involved are reversible. If we know the exact details (big if) of what happened, the processes can be reversed and the information retrieved. Both classical and quantum theory claim that micro reversibility is valid and provides for preservation of information (in principle). In 1976 I (Hawking) showed that black holes violate the principle of micro reversibility and result in the loss of information.Some other experts in theoretical physics claim otherwise, making statements like the following.
Hawking is wrong. You cannot undermine micro reversibility without destroying energy conservation. If Hawking is correct, the universe would heat up to some far out temperature. Since we do not observe the temperature increase, black holes cannot cause information loss. There must be some way to retrieve the information. Has anybody here read the article? Does anybody have some ideas on this?
Unfortunately, the article does not provide much proof or argument in favor of either point of view. I doubt if I could understand the arguments if they were presented.
Agreeing with Hawking (as I do), cannot be stupid, but I do not feel comfortable dismissing the other side without understanding how they arrived at their opinion.