The speed of light is only C "locally" in general relativity. The 
equivalence principle says that local observations of a freely-falling 
observer in a gravitational field will look just like local observations of 
an inertial observer in the flat spacetime of special relativity. "Local" 
means in a small region of spacetime--each observer has to only make 
measurements in their immediate region of space for a small period of time 
for the equivalence to work, and it only works precisely in the limit as the 
region of spacetime in which each makes their measurements becomes 
arbitrarily small.

So, in the context of general relativity, if you have a global coordinate 
system which covers a large region of curved spacetime, like Schwarzschild 
coordinates around a black hole, then it is perfectly possible that the 
coordinate speed of light will be different from C (it is also true in 
special relativity that if you use a non-inertial coordinate system, i.e. 
one in which observers at rest in that coordinate system are accelerating 
and experiencing G-forces as a consequence, then the coordinate speed of 
light can be different from C here as well). But even though light exactly 
at the event horizon would be at rest in Schwarzschild coordinates (and note 
that you have no obligation to use Schwarzschild coordinates when analyzing 
a black hole, you could use some other global coordinate system where the 
event horizon is not at rest), from the local perspective of a freefalling 
observer, the light will still be measured to move at C as the observer 
falls through the event horizon and passes next to the light beam. Also, if 
you imagine a series of buoys closer and closer to the event horizon, which 
use rockets to maintain a constant Schwarzchild distance from the BH, then 
an observer falling in will see each successive buoy flying past him at 
closer to C, with the measured speed of the buoy approaching C in the limit 
as the buoy's distance from the horizon approaches 0.

Jesse Mazer

>From: James N Rose <[EMAIL PROTECTED]>
>Subject: Blackholes imply 'C' is violated/invalidated.
>Date: Sat, 20 Jan 2007 07:37:08 -0800
>"Blackholes imply 'C' is violated/invalidated."
>Notion:  If the Speed of Light is not just a
>fixed constant but a fixed maxima, then, if Newton's
>3 Laws of Inertia are to be maintained, especially
>regarding 'equal & opposite' ...
>the current depiction of blackholes being able to
>constrain photons 100% infers that any random photon
>moving directly outward from the center-locus of a
>singularity can only be kept from forward linear motion
>by a force not just equal to, but necessarily greater
>than, its vector moment - presumed to be "C".
>If only just '-C', then Probability would require
>blackholes be never 'black', but accumulatively
>brilliant white - unless - 'C' is out-maximummed.
>Or, the model has an error - and the dynamics of
>light restriction/containment are of a wholly
>different nature than currently presumed.
>Jamie Rose
>Ceptual Institute

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