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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 /
npub1qq…j5nhv
2024-11-22 08:22:17
in reply to nevent1q…urte
Author Public Key
npub1qqm7nu2qf25xd3mw6y6cyp4v2wr7ktf43ymp5wqz4u8jvz76ymtsjj5nhvPublished at
2024-11-22 08:22:17Event JSON
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