Name: David
Status: educator
Grade: 9-12
Location: CA
Country: N/A
Date: 2/7/2005
Question:
Two questions about "escaping" a black hole that I could
not answer during a class discussion:
Putting aside tidal, radiation and relativistic effects for a moment
1. Could a "spaceship" that crossed the event horizon, nearly tangentially
accelerate by burning its fuel out of the "hole?"
2. Could an object be in a elliptical orbit around a black hole such that
the perigee was below the event horizon?
If either of these scenarios is possible what might one observe if one
were a passenger on the "spaceship" that took a "dip" into the "hole"?
Replies:
The event horizon is the point at which the speed of light is not sufficient
to escape. So no, you cannot cross that boundary without disregarding
relativity. And disregarding relativity makes it almost pointless to
discuss black holes.
For much more in depth explanations of what goes on under such strained
conditions of space/time, I highly recommend Stephen Hawking's book, "The
Universe In A Nutshell".
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