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Richard[_9_]

On 6/20/2014 10:35 AM, wrote:
Not THAT kind of black hole. Sheesh! So I have been reading off and on
about black holes for years. One of the theories about objects falling
into black holes says that an observer outside a black hole watching
an object fall into a black hole will see the object make it to the
event horizon and just hover there. I have not yet found an
explanation for this that I understand. Can anyone point me to a book
that explains this? I have also been thinking about what happens to
someone that crosses the event horizon in the case of extremely large
black holes. Since the gravity gradient would be small at the event
horizon the person crossing it would not be pulled apart at the time
of crossing. So now this person is hurtling toward the black hole and
if this person looks directly at the black hole there will be nothing
to see because the gravity is so high that escape velocity exceeds the
speed of light. But photons crossing the event horizon at an angle
should spiral into the black hole. So if the person inside the event
horizon looks in any other direction they will be able to see this
light. Finally, since the escape velocity just on the other side of
the event horizon is just a little higher than the speed of light
wouldn't that mean that someone crossing the event horizon would be
traveling at the speed of light? And if that is so then wouldn't this
person's life span be essentially infinite if observed from outside of
the black hole? And is this infinite lifespan the reason why the
person from our outside observer's point of view would seem to just
hover at the event horizon? If that's the reason it still doesn't make
sense to me. I think about this and talk to my friends and relatives,
some of whom are very smart, and I get no understanding. And drinking
more beer doesn't seem to help either.
Please feel free to correct me if any of the assumptions I have made
are wrong.
Eric

Can't help with a book, but the way I think of it -
think of a shock wave.

When a physical thing passes through a media faster than the media
can get out of the way, a shock wave is created (in that media).

Like supersonic flight, for instance.
Air molecules can't move out of the way quickly enough and pile up
into a high pressure wave. (air is a compressible media)

While I'm probably wrong, that's how I see the whole particle/wave
question in light and electromagnetic phenomenon.

The photon is the particle part; the wave is the shock wave created
by that photon passing through the media.

The next (unresolved) question is - what is the media?

Anyway, back to your question...

AT the event horizon, the acceleration level is 1.0 C (the speed of
light in a vacuum). Is that really a "weak" gradient?

I would think a person (or thing) would be pulled apart but a much
lower gradient that that...

For what it's worth.

Richard Lamb
(the Cavelamb)