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Old 03-January-2007, 12:04 AM
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Van Rijn Van Rijn is offline
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Quote:
Originally Posted by Peter Wilson View Post
Look, don't mince words.

If there was nothing beyond 5 Mpc, but otherwise everyting looked the same up to 5 Mpc, we would say, "The universe is 5 Mpc across and contracting." (According to GR as currently formulated, the universe must do one or the other: expand or contract.) It is not until we look beyong 5 Mpc that we observe expansion. So we say, "The universe is expanding."

But this is incorrect. It is not doing one or the other; it is doing both at the same time: contracting locally/expanding non-locally.
Rather, expansion is observable at larger scales, gravity dominates at smaller scales. There isn't a "5 Mpc" line in the sand, and expansion as well as gravitational force are accounted for.

Quote:
Duality, as you point jout, is observable.
I would hardly call the interplay of expansion, gravity and other forces, "duality."
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