Black Hole Firewalls Confound Theoretical Physicists

Jennifer Ouellette and Simons Science News report at Scientific American on a new hypothesis of the result of jumping into a black hole (involving Alice of 'Alice and Bob, beloved characters of various thought experiments in quantum mechanics'.

"Conventionally, physicists have assumed that if the black hole is large enough, Alice won’t notice anything unusual as she crosses the [black hole's event] horizon. In this scenario, colorfully dubbed 'No Drama,' the gravitational forces won’t become extreme until she approaches a point inside the black hole called the singularity. There, the gravitational pull will be so much stronger on her feet than on her head that Alice will be 'spaghettified.'

Now a new hypothesis is giving poor Alice even more drama than she bargained for. If this alternative is correct, as the unsuspecting Alice crosses the event horizon, she will encounter a massive wall of fire that will incinerate her on the spot. ..."

Physicists have dubbed this wall of fire a 'firewall', more or less the opposite of what you might expected that term to mean.