When you’re a little way outside a black hole (with no accretion disk), what you see when you face it is (as you say) not the absence of light emerging from the hole itself, but rather light emitted by the infalling matter that formed the hole in the distant past.
But this light will be *enormously* red-shifted, with the frequency and luminosity so low that for all practical purposes it will be utterly black.
Equally, inside the hole (free falling), unless something luminous fell in just ahead of you, you will see a big black circle.
An app with visuals here:
https://www.gregegan.net/PLANCK/Tour/TourApplet.html
The calculations behind it:
https://www.gregegan.net/PLANCK/Tour/TourNotes.html
Greg Egan
npub12c…gd38p
2024-11-22 08:22:17 UTC
in reply to nevent1q…xkz4
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2024-11-22 08:22:17 UTCEvent JSON
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