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To: PatrickHenry
So the universe is expanding faster than c, but nothing seems to be receding from us at that speed.

As it is to be expected. The distance at which the recessional velocity (caused by the expansion of space-time) is equal to "c" defines the boundary of an imaginary sphere around the point of observation, within which it is possible to observe objects. Objects beyond the boundary (if they exist?) would not be observeable to someone at the center of the sphere defined above, though they would still be part of the Universe, and would be observable from points located less than the previously defined boundary distance away from such objects.

I think "Physicist" referred to this distance as the "light horizon." It defines in a very practical way the limits of the observeable Universe, from a particular point of observation.

That was probably as clear as mud....

173 posted on 04/25/2002 1:12:38 PM PDT by longshadow
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To: longshadow
Objects beyond the boundary (if they exist?) would not be observeable to someone at the center of the sphere defined above, though they would still be part of the Universe, and would be observable from points located less than the previously defined boundary distance away from such objects.

I'm not getting that at all. The age of the universe is greater than the age of the luminous objects within it. So the oldest and most distant of luminous objects have had, as it were, all the time in the world to send their light to us. (The only exception I can think of would be a recently formed objects at a great distance.)

175 posted on 04/25/2002 1:18:57 PM PDT by PatrickHenry
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