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General
Relativity allows a repulsive term
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Einstein
proposed it to allow �steady state� universe
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He
decided it wasn�t needed after Hubble Law discovered
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Is the acceleration right?
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Could it be observational effect � dust dims
distant supernova?
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Could it be evolution effect � supernova were
fainter in the past?
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So far the results seem to stand up
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Still being determined:�
1)� density, 2) cosmological
constant
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With cosmological constant included, can have a �flat universe�
even
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with acceleration.
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Given �repulsion� need to use relativistic �geometrical�
definition of
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flatness, not the escape argument one given earlier.
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Energy (and equivalent mass) from cosmological
constant may provide
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density needed to produce flat universe.
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