Topic: the black hole paradox
mightymoe's photo
Thu 06/20/13 08:18 AM
Theoretical Physicists

If a new hypothesis about black hole firewalls proves correct, at least one of three cherished notions in theoretical physics must be wrong.

By Jennifer Ouellette and Simons Science News
From Simons Science News


Alice and Bob, beloved characters of various thought experiments in quantum mechanics, are at a crossroads. The adventurous, rather reckless Alice jumps into a very large black hole, leaving a presumably forlorn Bob outside the event horizon — a black hole’s point of no return, beyond which nothing, not even light, can escape.

Conventionally, physicists have assumed that if the black hole is large enough, Alice won’t notice anything unusual as she crosses the 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. As unfair as this seems for Alice, the scenario would also mean that at least one of three cherished notions in theoretical physics must be wrong.

When Alice’s fiery fate was proposed this summer, it set off heated debates among physicists, many of whom were highly skeptical. “My initial reaction was, ‘You’ve got to be kidding,’” admitted Raphael Bousso, a physicist at the University of California, Berkeley. He thought a forceful counterargument would quickly emerge and put the matter to rest. Instead, after a flurry of papers debating the subject, he and his colleagues realized that this had the makings of a mighty fine paradox.
The ‘Menu From Hell’
Paradoxes in physics have a way of clarifying key issues. At the heart of this particular puzzle lies a conflict between three fundamental postulates beloved by many physicists. The first, based on the equivalence principle of general relativity, leads to the No Drama scenario: Because Alice is in free fall as she crosses the horizon, and there is no difference between free fall and inertial motion, she shouldn’t feel extreme effects of gravity. The second postulate is unitarity, the assumption, in keeping with a fundamental tenet of quantum mechanics, that information that falls into a black hole is not irretrievably lost. Lastly, there is what might be best described as “normality,” namely, that physics works as expected far away from a black hole even if it breaks down at some point within the black hole — either at the singularity or at the event horizon.

Together, these concepts make up what Bousso ruefully calls “the menu from hell.” To resolve the paradox, one of the three must be sacrificed, and nobody can agree on which one should get the ax.


more here:
http://www.scientificamerican.com/article.cfm?id=black-hole-firewalls-confound-theoretical-physicists

Conrad_73's photo
Thu 06/20/13 08:23 AM
that must be what Dante saw!bigsmile

mightymoe's photo
Thu 06/20/13 08:29 AM

that must be what Dante saw!bigsmile


Dante might have been in the mushroom field that day...

Conrad_73's photo
Thu 06/20/13 08:36 AM


that must be what Dante saw!bigsmile


Dante might have been in the mushroom field that day...
thought it was Strawberryfields Forever?bigsmile

Conrad_73's photo
Thu 06/20/13 10:24 AM
so,the Thing not only Spaghettifies you,but cooks you and then eats you as well!Seems Disney had some Idea!
laugh

http://en.wikipedia.org/wiki/The_Black_Hole

mightymoe's photo
Thu 06/20/13 02:10 PM

so,the Thing not only Spaghettifies you,but cooks you and then eats you as well!Seems Disney had some Idea!
laugh

http://en.wikipedia.org/wiki/The_Black_Hole


seems simpler than all that... the closer you get, the more you liquify...

Conrad_73's photo
Thu 06/20/13 02:51 PM


so,the Thing not only Spaghettifies you,but cooks you and then eats you as well!Seems Disney had some Idea!
laugh

http://en.wikipedia.org/wiki/The_Black_Hole


seems simpler than all that... the closer you get, the more you liquify...
laugh

mightymoe's photo
Thu 06/20/13 03:27 PM

so,the Thing not only Spaghettifies you,but cooks you and then eats you as well!Seems Disney had some Idea!
laugh

http://en.wikipedia.org/wiki/The_Black_Hole


it's better to cook spaghetti before you eat it...