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## Main Question or Discussion Point

Alice is free-falling towards the event horizon (EH) of a black hole (BH) large enough such that local tidal forces are negligible. Bob is sufficiently ("infinitely") far away such that he is unaffected by the BH and inertial. Bob's view of Alice is well established: she will appear to slow down and red-shift as the approaches the EH, eventually "freezing" and "dimming to nothingness" before she ever appears to cross it.

The question is, what is Alice's view of the outside world? I've looked through many sources (GR textbooks, Googling, etc) and so far have been unable to find an answer to this. A few people seem to think that Bob would appear blue-shifted, but there is some contention as to whether this blue-shifting would be asymptotically infinite as the EH is approached. Is there a well-established answer?

Thanks in advance,

The question is, what is Alice's view of the outside world? I've looked through many sources (GR textbooks, Googling, etc) and so far have been unable to find an answer to this. A few people seem to think that Bob would appear blue-shifted, but there is some contention as to whether this blue-shifting would be asymptotically infinite as the EH is approached. Is there a well-established answer?

Thanks in advance,