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What happened to the black hole firewall theory? Back in 2012, some physicists apparently came up with strong evidence that one of three things must be wrong for black holes to work the way we thought they did:

  1. Unitarity
  2. the Equivalence Principle or
  3. the Event Horizon.

It seems that for a week the media had a flurry of reports that physicists including Stephen Hawking were dumping the event horizon for things like an "apparent horizon" and then... silence. I haven't heard anything about the firewall theory since.

Are physicists still trying to work out a solution? Did someone realize that the theory was flawed in some way? It seemed like a big deal at the time so I find it odd that it seems that no one is talking about it right now, although that might just be my over-reliance on general media for physics news.

Jens
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Nullius in Verba
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1 Answers1

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The field of quantum black holes is a hot topic of research right now, and the firewall proposal is still being debated.

I have the feeling that no one really takes the proposal seriously. By saying this I don't mean that it was a bad paper, on the contrary it's a nice thought experiment that forced us to think even more about the black hole information paradox. The point is that the authors found an inconsistency between the three main assumptions they have made, that is (1) local quantum field theory description is valid, (2) unitarity and (3) smoothness at the horizon. Actually there are more assumptions, and one can question if they are appropriate. Anyway, they assumed that the most conservative viewpoint was to give up the smoothness and to introduce a firewall at the horizon.

The argument is subtle and some authors claimed to have debunked the proposal, but it's fair to say that a conclusive argument against the proposal is still missing.

Jens
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Rexcirus
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