G'Day Rob;
Long time .. no hear .. good to see you back in these parts !
I was having recall about our previous discussions about the similarity of this and BH Event Horizons. I think I recall leaving that discussion with the QM/String Theory view that 'frozen' images break into ever increasing smaller components (vibrating strings) covering the entire EH. At the moment though, I'm trying to get the Relativity perspective embedded in my brain. The relativists seem to always refer to the 'blinking out' phenomenon and I think this is derived from the formal definitions posted by Steven. (I'll have to have more of a think about the ramifications of these).
There's another issue also .. raised by Rolf … the redshift one. In theory, redshift would cause the wavelength to become just about infinite wouldn't it ?
What happens to the energy of the photon if/where this happens ?
Cheers