If you mean the world lines of infalling dust particles on that Penrose diagram, I’m not sure; I don’t know exactly what coordinate system is used there.
BTW, this other page I wrote on things falling into black holes might also be of interest:
https://www.gregegan.net/SCIENCE/FiniteFall/FiniteFall.html
Greg Egan
npub12c…gd38p
2024-11-24 13:56:55 UTC
in reply to nevent1q…9gjv
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