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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?

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    $\begingroup$ When I see a question like this my first instinct is to ask "Did you read the paper? Or even the abstract?" $\endgroup$ Jan 29, 2014 at 16:37
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    $\begingroup$ Yes, I read the paper, but I'm not an expert on physics. $\endgroup$ Jan 29, 2014 at 16:40
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    $\begingroup$ @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. $\endgroup$
    – Danu
    Jan 29, 2014 at 16:41
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    $\begingroup$ 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. $\endgroup$ Jan 29, 2014 at 16:47
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    $\begingroup$ 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. $\endgroup$
    – Kyle Kanos
    Jan 29, 2014 at 16:53

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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).

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  • $\begingroup$ 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. $\endgroup$ Jan 29, 2014 at 18:21
  • $\begingroup$ Someone should update the Wikipedia article. $\endgroup$ Jan 29, 2014 at 18:21
  • $\begingroup$ 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. $\endgroup$
    – LoveU
    Jan 29, 2014 at 22:55

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