Labguy said:I probably didn't explain my point very well because I have now even confused myself... , but I guess my main point is that no gravity or other source of energy can cause a violation of SR (I said GR earlier.. :yuck:) Not because SR is the Gospel, it has just been verified too many times to leave much doubt.
And this is compatible with what Taylor and Wheeler say above. The easy way to think about this is the intuitive way: if you fall across the horizon at < c then the definition of a horizon is not met, for info from you could then escape the horizon. If you fall across the horizon at > c then someone hovering above the horizon could directly measure your velocity to be >= c, violating SR. Then you must cross the horizon at exactly c (and that is supported by GR's math, and it applies regardless how you got to the horizon--you could have plunged into it or been hurled to it at relativistic velocity or dropped from any height or accelerating into it with rocket engines). Then if you fall across the horizon next to something else, your velocity relative to it is zero (because it crosses at your same exact speed); that's the only velocity you can directly measure at the horizon.