Three weeks ago, Steinhauer’s group reported results from a new experiment in which they have now measured the temperature of the fluid black hole:
Observation of thermal Hawking radiation at the Hawking temperature in an analogue black hole
Juan Ramón Muñoz de Nova, Katrine Golubkov, Victor I. Kolobov, Jeff Steinhauer
While the measurement is not very exact owing to the noise in the system, the result agrees with Hawking’s prediction, at least to the precision that the experiment allows to identify a temperature to begin with.
The authors also point out in the paper that they see no evidence of a black hole firewall. A black hole firewall would have been conflict with Hawking’s prediction according to which radiation from the black hole does not carry information.
It’s not an exact analogy to a natural black hole but Hossenfelder thinks it’s good enough for the purpose.
Now, if the string theory calculations were correct then the information should leak out of the black hole. If you want to avoid a black hole firewall – because that hasn’t been observed – you need to break the entanglement across the horizon. But this isn’t compatible with the earlier results of Steinhauer’s group.
So, this result documents that black holes in a box do not behave like string theorists think they should. Of course the current measurement results have large uncertainties and will have to be independently reproduced before the case can be considered settled. But I have little doubt the results of the Steinhauer group will hold up. And I’ll be curious to hear what string theorists say about this. “Hawking temperature of black holes measured in fluid analogue” at BackRe(Action)
Well, we are very likely to hear what string theorists say about this but keep in mind, string theory is in no more danger of disconfirmation by the state of the evidence than space aliens are. It serves a need. It is one of a number of theories that enable a much-needed multiverse, so those strings will just keep on stringing…
See also: “Perhaps physics has slipped into a post-empirical era…” (from a review of Hossenfelder’s book at Physics World)
Post-modern physics: String theory gets over the need for evidence