From: SFPhysics@aol.com
Date: Wed Oct 18 2000 - 02:49:16 PDT
From: SFPhysics@aol.com Message-ID: <29.b85869a.271ecc1c@aol.com> Date: Wed, 18 Oct 2000 05:49:16 EDT Subject: Re: Light Rays, Black Holes, & Naked Singularities
> Regarding light travelling into black holes. I can imagine light headed
> toward a black hole, it would be bent into it, but would always just miss
> it, as it is a singularity, ie. very small; this would cause the light to
> orbit about the black hole in ever tightening rings (as the black holes
> mass increases), at the speed of light. Centrifugal force is provided by
> the black hole's gravity. what happens as the circle is smaller than the
> wavelength of the light? Now, I know nothing about such things, but see no
> reason that the light speed must change, other than it is travelling
> through matter that has been converted to quarks and electrons by tidal
> forces, or whatever is gong on near the singularity. I am guessing that
> the acceleration on light caused by mass changes direction, and not speed;
> that space-time is bent, but the speed of light remains a constant. I can
> envision light collapsing into the hole at some point as the wavelength is
> larger than the flight radius; I imagine that the energy from the light
> would be put into something akin to big bang sort of interactions. I write
> this to encourage Paul or whoever to correct it; I really do not have a
> clue. Eiger
> Steven Eiger, Ph.D.
>>
Steven:
There are two concepts here. The event horizon and the singularity. They
are not one in the same.
Light has no rest mass so it won't spiral down into the black hole by losing
momentum. If a light ray bends in the warped space around a gravity well
such as our star Sol, it does not slow down or fall in. The same happens
with a black hole gravity well, if the ray is lucky enough to pass nearby it
gets deflected. Only if it touches the event horizon at even a small angle
will it drop in and out of our universe. There may be black holes so small
that they have no event horizon, these are called naked singularities and
currently exist in theory only. You postulated what would happen if a light
ray interacted with a naked singularity. The answer logically would be
nothing. Light waves, radio waves, infrared waves, UV waves, etc., that are
larger than the singularity should just pass right by as they do with single
atoms and molecules. Theoretically you could be sitting on a tiny naked
singularity right now and not know it.
The evidence for "normal" black holes like Cygnus X-1 shows that an extended
event horizon covers the singularity. Event horizons can extend far out from
where the actual "hole" in space is. The event horizon is the distance from
the singularity below which the gravity acceleration exceeds the velocity of
light. The singularity would be at the center of the spherical event horizon.
The universal law of gravity states that everything in the universe is
attracted to everything else and so it is with black holes. Right now, as
you sit in front of this computer you are being pulled by many black holes;
but, you won't fall into one because the pull is so small and at such great
distances. Too much science fiction has left the impression that black holes
"suck" everything into them. Not true, we have evidence that at least one
binary star system exists where the visible star is circling a black hole.
It will circle the black hole forever unless some force lessens its momentum.
The centripetal force provided by the gravity well cannot slow a light ray
down or pull it in. The ray has to hit the event horizon to be captured.
Again I'm clear as mud, right?
Thank goodness you didn't ask about Quantum Foam,
Al Sefl
Whose answers may have no bearing on reality................
Oh, Paul, jump in anytime and lend some HELP here..........
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