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## Main Question or Discussion Point

Here is an article Count Iblis recommended me:

http://arxiv.org/abs/gr-qc/0609024

This article is quite interesting but I am puzzed here:

Page 11

http://en.wikipedia.org/wiki/Event_horizon#Interacting_with_an_event_horizon

http://arxiv.org/abs/gr-qc/0609024

This article is quite interesting but I am puzzed here:

Page 11

However, even without the radiation, an infalling observer is not supposed to cross it - that is what I was thinking:The infalling observer never crosses an event horizon, not because it takes an infinite time, but because there is no event horizon to cross. As the infalling observer gets closer to the collapsing wall, the wall shrinks due to radiation back-reaction, evaporating before an event horizon can form. The evaporation appears mysterious to the infalling observer since his detectors don’t register any emission from the collapsing wall. Yet he reconciles the absence of radiation with the evaporation as being due to a limitation of the frequency range of his detectors

http://en.wikipedia.org/wiki/Event_horizon#Interacting_with_an_event_horizon

Also, if (in his frame) the radiation is so low-energy that the wavelength can not be detected, then how the evaporation can be so fast? I suspec that somewhere in the article there is an error - they mixed frames of distant and infallinf observers....In practice, all event horizons appear to be some distance away from any observer, and objects sent towards an event horizon never appear to cross it from the sending observer's point of view (as the horizon-crossing event's light cone never intersects the observer's world line).

Observers who fall into the hole are moving with respect to the distant observer, and so perceive the horizon as being in a different location, seeming to recede in front of them so that they never contact it.