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| Sam Wormley |
 Posted: Thu Mar 31, 2005 9:42 am |
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From Ned Wright's
News of the Universe
Cosmic Ripples instead of Dark Energy?
16 Mar 2005 - Rocky Kolb et al. have suggested that large scale ripples
in space-time could explain the observations of the accelerating
Universe that seem to require dark energy - the vacuum energy density
that is equivalent to the cosmological constant. Despite issuing press
releases and getting some coverage, even in the Los Angeles Times
although 10 days later, I find their arguments lacking. In Einstein's
General Relativity, the local metric determines the local stress-energy
tensor, so the large scale ripples do not change the need for a
negative pressure and hence a vacuum energy density or cosmological
constant based on the supernova observations of the local geometry.
[this article withembedded links: http://www.astro.ucla.edu/~wright/cosmolog.htm#News] |
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| John Sefton |
| Posted: Thu Mar 31, 2005 5:23 pm |
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Sam Wormley wrote:
[quote:2809f7752b]From Ned Wright's
News of the Universe
Cosmic Ripples instead of Dark Energy?
16 Mar 2005 - Rocky Kolb et al. have suggested that large scale ripples
in space-time could explain the observations of the accelerating
Universe that seem to require dark energy - the vacuum energy density
that is equivalent to the cosmological constant. Despite issuing press
releases and getting some coverage, even in the Los Angeles Times
although 10 days later, I find their arguments lacking. In Einstein's
General Relativity, the local metric determines the local stress-energy
tensor, so the large scale ripples do not change the need for a
negative pressure and hence a vacuum energy density or cosmological
constant based on the supernova observations of the local geometry.
[this article withembedded links:
http://www.astro.ucla.edu/~wright/cosmolog.htm#News]
Now we're getting close.[/quote:2809f7752b]
And galaxies are a result of
large-scale rotation.
John |
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