r/Physics • u/Negative_Test774 • 17h ago

Question Has anyone actually solved the black hole firewall paradox?

I’ve been reading about the AMPS argument and how it challenges the equivalence principle by suggesting an infalling observer would hit a "firewall" at the horizon. I know there are many proposed resolutions (ER=EPR, complementarity, state-dependence, etc.), but I’m wondering if there’s a widely accepted solution at this point. Has the paradox been resolved in any definitive way, or is it still an open problem in quantum gravity?

0 Upvotes

50% Upvoted

7 comments sorted by

13

u/WallyMetropolis 17h ago

It isn't even widely accepted that black holes have a firewall.

4

u/11zaq Graduate 11h ago

The microscopic understanding is still poorly understood. But at the least, the recent work about islands and replica wormholes (as well as AdS/CFT) strongly suggest that black hole evaporation is unitary. So that assumption from AMPS probably needs to stay, which narrows the contradiction to one of the other assumptions being false. That's progress, even if it isn't a full answer.

1

u/me-gustan-los-trenes 11h ago

What does it mean that the evaporation is unitary?

2

u/11zaq Graduate 5h ago

It means that if I have a star or a cloud of dust that is in a pure quantum state, it collapses into a black hole, and that black hole fully evaporates into a cloud of Hawking radiation, that final state of Hawking radiation is also in a pure quantum state.

3

u/cabbagemeister Mathematical physics 14h ago

This year marks 50 years of trying to understand the black hole information paradox - there is an event at simons for it

https://scgp.stonybrook.edu/archives/45328

So the answer is no, nobody has figured it out

1

u/Negative_Test774 8h ago

But is it widely accepted that blackholes have firewalls?

3

u/cabbagemeister Mathematical physics 8h ago

No