Re:Strangeness of Black Holes
by l33tman on Friday January 18, 2019 @08:57AM
(#18939286)
The perfect orbit geodesic is infinitely thin and therefore unstable due to quantum mechanics. So even if a photon is injected at the perfect orbit it would not stay there, it would fall in or eject. Besides, even without invoking QM, any other matter that actually falls into the hole afterwards would inflate the event horizon, causing those photons caught in the perfect orbit to now exist just infinitesimally within the orbit and fall in.
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Re:Strangeness of Black Holes
by soVeryTired on Friday January 18, 2019 @09:57AM
(#18939686)
Do you need quantum mechanics to see that a photon would fall in or eject? Presumably a little movement from the black hole would do the trick too.
Right, but the QM view tells us that even a perfectly stationary chargeless black hole in a perfect vacuum alone in a perfectly smooth universe would still experience fluctuations in its event horizon. Unlike the Classical view, QM reveals that even in principle there exists a degree of instability in the horizon.