Warp wrote:
> on. In fact, Hubble's law predicts that galaxies beyond a certain
> distance, known as the Hubble distance, recede faster than the speed
> of light. For the measured value of the Hubble constant, this distance
> is about 14 billion light-years."

Here's an interesting question, tho: Consider the galaxies that are 
receding at (1-epsilon)*c from us. Galaxies[1] that will cross the 
boundary from timelike to spacelike distances in (say) the next year.

It can't accelerate faster than light, right? Is it going to go slower 
and slower, like an object falling into a black hole will, from our 
point of view?

Hmmm, thinking on it, if the expansion is caused by expanding space, 
maybe time doesn't seem to slow down? Do you not get relativistic time 
dilation from expanding space? If not, why do photons red-shift? If so, 
why would we see any galaxy ever "cross" the speed of light as it recedes?

I did see an interesting speculation once that the 3-degree background 
radiation was actually all the galaxies piled up against the lightspeed 
barrier, but I have no idea how much sense that makes.

[1] Or planets, or specs of dust, or whatever's small enough for you to 
accept this happens.
-- 
Darren New / San Diego, CA, USA (PST)
  Helpful housekeeping hints:
   Check your feather pillows for holes
    before putting them in the washing machine.

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