## How Would an Astronaut Falling Into a Black Hole Die? 412

ananyo writes

*"According to the accepted account, an astronaut falling into a black hole would be ripped apart, and his remnants crushed as they plunged into the black hole's infinitely dense core. Calculations by Joseph Polchinski, a string theorist at the Kavli Institute for Theoretical Physics in Santa Barbara, California, though, point to a different end: quantum effects turn the event horizon into a seething maelstrom of particles and anyone who fell in would hit a wall of fire and be burned to a crisp in an instant. There's one problem with the firewall theory. If Polchinski is right, then either general relativity or quantum mechanics is wrong and his work has triggered a mini-crisis in theoretical physics."*
## Re: Somebody, quick! (Score:5, Insightful)

The /. I knew and loved a decade ago is gone.

## Re:We must find out for sure! (Score:4, Insightful)

The problem is that we won't be able to observe what happens to them inside the event horizon. If you want to be sure, you have to go yourself.

## Bad headline (Score:5, Insightful)

TFA is an interesting article about a physicist apparently discovering an inherent contradiction between general relativity and quantum mechanics. The "black hole" stuff is really just the context that led to the apparent contradiction: the real issue is much deeper than that. It's depressing that the real underlying hypothesis isn't considered newsworthy, and the editor feels the need to lead with the "black hole" stuff.

## Re:Quantum mechanics and relativity (Score:5, Insightful)

This isn't true.

QM and *special* relativity get along just fine. When you combine them in a simple way you get predictions like antimatter, the fine structure of the hydrogen atom, and so on. If you do this in a more detailed way, using quantum field theory, you get the fantastically accurate predictions of quantum electrodynamics, the theory of quantum chromodynamics that can't be solved with pen and paper but which still gives accurate predictions when done on supercomputers, and so forth.

And there's nothing forbidding QM from playing nice with general relativity, either; we just don't know how it works yet. There are some models, like lattice quantum gravity, that seem quite promising.

## Re:Gravitational time dilation (Score:2, Insightful)

You got that exactly backwards.

Refer to Stargate SG-1 episode "A Matter of Time" (Season 2 Episode 16): "

SG-10 is stranded on planet P3W-451, which is close to a newly formed black hole. The SGC opens the gate to find out what happened, but they cannot shut it down afterwards. Soon they realize that since the planet is near to a black hole, its intense gravity is causing time dilation, so if they do not shut down the gate very soon, it will destroy the SGC, and in time, the entire planet."People outside the base have much longer to think about what's happening inside the base. e.g. At one point Hammond spends 18 hours off base while those inside the base think he was only gone for ~20 minutes.

## Misleading (Score:2, Insightful)

The whole "what would happen to an astronaut" is the misleading sensationalist that's been pollution this site lately. It seems they're really going from "News for Nerds" to "Fox News for people who may buy computer and sciency stuff from places like Thinkgeek" (though thinkgeek is awesome BTW) in order to gain bigger audience.

End result is it drives away the core audience that used to make this site awesome, as it dumbs down the really interesting science parts beyond recognition.

## Re:Gravitational time dilation (Score:2, Insightful)

But that is pretty much what would happen according to all theory, that is what the idea was based on.

Most of SG series is based on working and partial theories, and a few controversial ones too. (like man vs machine consciousness in that life has soul where machine does not)

## Re:Quantum mechanics and relativity (Score:5, Insightful)

And there's nothing forbidding QM from playing nice with general relativity, either; we just don't know how it works yet.

Translation:

As currently formulated, at least one of quantum mechanics and general relativity is wrong, although like Newtonian mechanics or pre-relativistic optics, they will undoubtedly continue to be practical and very accurate approximations.We knew this as soon as quantum mechanics was developed.