
The Question
(Submitted March 14, 1997)
Just curious about Black holes, and I wanted to know if the gravitational
field of a black hole would pull an object in faster than the speed of
light. If I understand correctly objects cannot go faster than the speed
of light our they would be going back in time. If the acceleration of a
black hole is constant, would an object that got sucked into a black holes
velocity increase beyond the speed of light the closer it got to the black
hole?
The Answer
The answer to your question is that the motion
of a particle near a black hole is not governed by Newton's
laws of motion in the familiar sense. The correct equations
for motion near a black hole predict that an object on a radial
path into the hole will have a velocity which approaches
the speed of light as the object approaches the event horizon.
For more information, I can only refer you to a textbook on
general relativity, such as the one by Steven Weinberg
("Gravitation and Cosmology..." 1972 (Wiley: New York).
I hope this is of some help.
Tim Kallman
