SCIENCE
Because the expansion of the universe is accelerating, there will come a time when objects will be receding at more than the speed of light, and we won't be able to see them. This is termed the event horizon by Krauss and Shearer. Is it possible to know what already lies beyond this horizon?
Not everything is receding from us. Galaxies near our own, Andromeda for example, are bound to the Milky Way by gravitational forces and will gradually come together forming one super galaxy, but outside that region eventually there will be nothing detectable. At that point, the pieces of the Big Bang puzzle will no longer be observable. Then cosmologists will confront a paucity of clues about the universe's past history.
Now we short-viewers may wonder why records and data already collected might not serve the historic need, but remember along the way our sun will expand to red giant size and archives will likely not survive all of that.
In addition to wondering what lies beyond the event horizon, we might ponder what events in the history of the universe have already been lost forever. Black holes swallow up not only material but information as well. Theoretical physicists are able to infer what events occurred very soon after the Big Bang, but you never hear anything about conditions preceding the Big Bang. It might be that we never know.
(One hundred trillion is fourteen zeroes incidentally.)
Information for this program was taken from the March edition of Scientific American.
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