Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

This question already has an answer here:

Stephen Hawking recently said that black holes do not exist. According to Wikipedia, black holes are predicted by General Relativity. So it would seem to follow that Stephen Hawking believes that General Relativity is wrong.

Am I missing something?

share|improve this question

marked as duplicate by Brandon Enright, ja72, Kyle Kanos, dmckee Jan 29 at 16:36

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

2  
When I see a question like this my first instinct is to ask "Did you read the paper? Or even the abstract?" –  dmckee Jan 29 at 16:37
2  
Yes, I read the paper, but I'm not an expert on physics. –  Craig Feinstein Jan 29 at 16:40
1  
@CraigFeinstein I think you did not read the academic paper published by Hawking. A careful examination will show you that he never asserts that black holes don't exist. –  Danu Jan 29 at 16:41
    
He said, "The absence of event horizons mean that there are no black holes." He also says, "A different resolution of the paradox is proposed, namely that gravitational collapse produces apparent horizons but no event horizons behind which information is lost." These two statements together imply that he believes that black holes don't exist. –  Craig Feinstein Jan 29 at 16:47
    
The continuation of the first quote is, in the sense of regimes from which light can't escape to infinity. That is, there are no event horizons (what your 2nd quote says) which is different from the black hole itself. –  Kyle Kanos Jan 29 at 16:53

1 Answer 1

up vote 1 down vote accepted

No, he does not think that GR is wrong. Actually, in his article on arxiv, he gives some ideas in order to (try to) solve a problem associated to the information paradox for evaporating black holes. That would mean that the usual idea of black hole we have would not longer be accurate. It does not imply that GR is wrong (at least on the domain of validity where we believe it provides a pretty good description of physics).

share|improve this answer
    
So then we have a contradiction. If he doesn't believe in BHs but believes in GR, this contradicts the conventional wisdom that GR implies BHs, as is stated in the Wikipedia article on BHs. –  Craig Feinstein Jan 29 at 18:21
    
Someone should update the Wikipedia article. –  Craig Feinstein Jan 29 at 18:21
    
Not really. Because what Hawking is talking about is actually on the wedge of validity of GR. It does involve quantum effects ; something that GR is not able to take into account. To be accurate, nobody believes in GR because we know there should be another theory to describe quantum gravity. But, as long as some assumptions are verified, GR is a theory that describe the physics of gravitation in a very convincing way. And if you have even more restricting assumptions, you don't need GR ; you can use Newtonian theory. It will gives you very good results, as long as used in a correct framework. –  LoveU Jan 29 at 22:55

Not the answer you're looking for? Browse other questions tagged or ask your own question.