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Black Holes
By Brad Rodgers (P1930) on Saturday, February 19, 2000 - 07:55 pm:

How can a black hole's horizon become larger if no change takes place inside of it from our perspective.

Brad - age 14

By Sean Hartnoll (Sah40) on Saturday, February 19, 2000 - 10:27 pm:

There is a lot about black holes here.

About your question, we have no idea what is happening beyond the event horizon. There is nothing contradictory about the size of the black hole (event horizon) changing.

Sean

By Brad Rodgers (P1930) on Sunday, February 20, 2000 - 03:41 am:

Thanks

By Neil Morrison (P1462) on Tuesday, February 22, 2000 - 06:40 pm:

In SYS (Scottish A-level type thing) Physics, there is a part about gravitation orbits etc that says things like calculating radii of black hole (or something). I have to go now, but I'll maybe go into more detail if you want.