Warp wrote:
>   I must admit that I have no idea what the GR equations say about this,
> but I got the impression that inside the event horizon all geodesics point
> straight at the singularity, when going forward in time.

I wouldn't think they point *straight* at the singularity, unless a 
photon spiraling to its death is considered to be going in a "straight" 
line. The fact that two particles can take different paths starting from 
the same place would seem to imply that "straight at the singularity" is 
either mistaken or so counter-intuitive that I don't understand what it 
means. :-)

Take a photon that's halfway to the S-radius (for some meaning of 
"halfway"). Fire it perpendicular to the radius (for some meaning of 
"perpendicular"). I would think the photon would follow a spiraling 
descent, rather than fall straight towards the singularity. Fire one in 
the opposite direction. It'll take a different path. If photons always 
follow geodesics, either you can have multiple geodesics pointing 
"straight at" the singularity, or your impression is wrong. I don't know 
which it would be, tho.

> I would expect
> that no geodesic points away from the singularity at any point.

Yeah. I'm just not sure the math works the same when you consider the 
whole universe to be the black hole. If it were true, how could you 
measure the "center" of the black hole? *I* sure don't understand the 
subject well enough to be sure. I'm just saying what I've heard other 
reputable GR scientists say.

Fun to babble about it, tho. ;-)

-- 
   Darren New / San Diego, CA, USA (PST)
     It's not feature creep if you put it
     at the end and adjust the release date.

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