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I am no physics major nor math major to this but merely an amateur cosmology enthusiast, so in my previous inquiries I wasn't able to find anything on the premise that if all black holes obviously have different masses (which we know they do, as all objects do), and we know that each black hole's gravitational pull exceeds the speed of light $c$ so my question being: is it possible the escape velocities of some black holes are quite possibly much greater than $c$ itself?

Let's say if there was "super light", light that goes $10c$ (10x the speed of normal light), is it possible that the gravity of some black holes could be so extreme that it would greatly exceed even $10c$? and beyond etc. Or do black holes only "defeat" light's escape velocity by just above $c$? If I am not understand it correctly, please feel free to correct, thanks.

Qmechanic
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Deadweed1
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1 Answers1

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Escape velocity is position-dependent - the closer you are to a massive body, the faster you need to move to escape its gravitational field. We typically talk about the escape velocity at the "surface" of a body, but that's a bit of a tricky thing for a black hole.

The event horizon could be considered the "surface" of a black hole, and is the region from which light cannot escape. At positions outside the event horizon, the escape velocity is below c and light can escape. As you cross the event horizon, the escape velocity exceeds c - once it crosses the event horizon, even light cannot escape. Inside the event horizon, the escape velocity will continue to increase as you approach the singularity. By the time you are mere Planck lengths from a cosmic mass packed into a near-zero volume, the escape velocity will far exceed c.

All black holes have escape velocity equal to c at their event horizon by definition, and escape velocities much higher than c when approaching the singularity.

Nuclear Hoagie
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