nemesis <nam### [at] gmailcom> wrote:
> Darren New escreveu:
> > triple_r wrote:
> >> In other words, as seen by an outside observer, you reach the event 
> >> horizon and
> >> sit.  Forever. 
> > 
> > So at what point does the black hole increase in mass? Why would a black 
> > hole ever grow if nothing falls thru the event horizon?

> He's talking about what is seen from an external observer, which is the 
> same explanation Hawking gave in one of his books.  The observer sees a 
> kind of after image that seems to ever approach the event horizon 
> without ever touching it, but in reality the crossing of the EH already 
> took place and nothing of what happens in the inside is seen...

  Besides, the mass of a spherical object, as measured from outside the
sphere, is independent of how the mass is distributed. It could be all
in the center or it could be all evenly distributed. From the outside
it would measure the same.

  That's the reason why you can eg. calculate orbits assuming the Earth
is a point, rather than a sphere. (Well, as long as the orbit doesn't
collide with the surface of the Earth, of course.)

-- 
                                                          - Warp

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