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Physics, Astronomy & Cosmology / Re: Why can't light penetrate the event horizon?
« on: 26/01/2017 13:57:26 »I'm limiting the analysis to radial motion, but you (jeffryH) may be right. I think Viascience gets his equation of motion for the photon by setting ds=d(angle)=0 so that dr./dt=(1-rs/r)c...Remember what Einstein said: "a curvature of rays of light can only occur when the speed of light is spatially variable". This article is worth a read: Is the speed of light everywhere the same? It's by relativist Don Koks, who says this: "If you're fixed to the ceiling, you measure light that is right next to you to travel at c. And if you're fixed to the floor, you measure light that is right next to you to travel at c. But if you are on the floor, you maintain that light travels faster than c near the ceiling. And if you're on the ceiling, you maintain that light travels slower than c near the floor". The vertical light beam speeds up as it ascends from the floor to the ceiling. The vertical light beam emitted just above the event horizon speeds up as it gets away from the black hole. The vertical light beam emitted at the horizon isn't actually emitted because at that location the speed of light is zero.
PS: black holes can form even when nothing passes through the event horizon. For an analogy imagine you're a water molecule. You alight upon the surface of a hailstone. You can't pass through this surface. Instead you are surrounded and then buried by other water molecules. So the surface can pass through you.