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Math Shows Some Black Holes Erase Your Past and Give You Unlimited Futures (vice.com)
dmoberhaus writes: An international team of mathematicians has found that there are theoretical black holes that would allow an observer to survive passage through the event horizon. This would result in the breakdown of determinism, a fundamental feature of the universe that allows physics to have predictive power, and result in the destruction of the observer's past and present them with an infinite number of futures. The findings were detailed in a report published last week in Physical Review Letters.
Only difference between black holes and neutron stars is black holes overcome pauli and everything collapses into a shared state. Big whoop. Assertions of "infinite density" are nonsense. There is no evidence single massive shared states have exactly zero extent or that length is not quantized and energy sure as heck is not infinite so jumping to "infinite density" conclusions is premature at best. Neither is there anything special about escape velocities approaching C. Of course there are effectively incalculable (yet not unlimited) futures embedded in the ginormous quantum state making up the black hole.
Infinite density is a scam.
Determinism is a scam.
(Ir)reversibility as constructed is essentially a tautology.
In quantum physics the approach of following the mathematical theory to its logical conclusion, how weird that may sound, has been quite successful. In any case such speculations make sense to test a theory and see where it leads to. Maybe it'll even lead to possible experimental tests of the theory (although I don't think humanity will have access to a black hole (specifically one that is big enough) to play around with.
The Einstein-Podolsky-Rosen-Paradoxon is a good example of following a theory (here quantum mechanics) to it's logical conclusion. Effectively the "paradoxon" exposes the nonlocality of quantum mechanics i.e. it implies "spooky actions at a distance", a picture that clashes with our classical world view. Based on this an experiment was thought up, a test of the "bell inequality". Basically any classical theory that preserves locality should always fulfil the bell inequality. OTOH quantum mechanics predicts a violation of the bell inequality in experiments specifically designed for that purpose. Such experiments then showed a violation of the inequality. This means, that a classical theory (which would include locality) can not explain those experimental results (which are predicted by quantum mechanics).
So the speculations of Einstein, Podolsky and Rosen about the strange consequences of quantum mechanic theory led to a fundamental insight about the nature of reality, namely that there are aspects of it that can not be explained by a "classical" theory that includes locality.
So if one wants to test a mathematical description of reality one has to follow the mathematics to its logical conclusions and if possible test if these apply to the real world. Even if such a test is not possible it is often helpful to see what the implications of a mathematical model are. Maybe it leads to a better understanding, uncovers contradictions or shows that a theory is incomplete, but in some cases it can also lead to a deeper understanding of reality.
"By the way if anyone here is in advertising or marketing... kill yourself." -- Bill Hicks
I hereby demonstrate my complete lack of understanding slashdot readers by linking to the full article on arxiv It's kind of an interesting mathematical exercise in the physics of charged black holes under various conditions but obviously does not reflect reality. For example, you would need a large positive cosmological constant, and an extreme ratio of charge to mass for this to be relevant. Further the clickbait headline implies some kind of retroactive erasure of the onserver when in reality it just means you can't reconstruct the past from future observations due to a breakdown in how the math works. This may not even be true at all because we know that general relativity does not fully describe spacetime at the extremes found at the surface horizons of black holes anyway.