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#21
Jan18-06, 05:11 PM
Emeritus
Sci Advisor
P: 7,436
Quote Quote by SpaceTiger
I've been trying to find the time to put together a good summary of cosmological horizons, but I'm afraid I'm still falling short. Start by taking a look at hellfire's brief review:

Horizons
I don't think this is the link you intended :-(

There may exist an event horizon; that is, a comoving distance at which a light ray fired from earth at the present time would never reach. I don't know if that's what you mean. It's not the same as a black hole event horizon, but is, in some ways, analogous to it.
They way I recall it is that such a horizon does in fact exist in FRW cosmologies IF the expansion of the universe is acclerating. (Current data suggests that this is the case). I suppose I should go look for some references to support my recollections.

If the expansion of the universe is deaccelerating, we will (again IIRC) see all of it eventually.