Talk:Dark matter
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There was a mistake in the article. Dark energy is accounted for the universe acceleration whereas dark matter is accounted for galaxies disintegration.
--Tomer Ish Shalom 02:26, 9 Jun 2005 (UTC)
galaxy disintegration?
I have never heard of this disintegration stuff before. Could you provide references? --Philipum 07:05, 9 Jun 2005 (UTC) www.groklaw.net/article.php?story=2005061901241583
I would be glad to. A popular explanation can be found at dark matter tutorial (http://www.astro.queensu.ca/~dursi/dm-tutorial/dm0.html) Note in particular the concept of rotation curves for galaxies.
--Tomer Ish Shalom 10:30, 9 Jun 2005 (UTC)
Dark energy does indeed account for the acceleration of the universe. The reason that confusing element was in the article is that it was once thought, before measurements of dark energy, that precise measurements of the amount of matter in the universe would decide the ultimate fate of the universe. It is now thought that the universe is geometrically flat, so this is not such an issue any more.
This galactic disintegration stuff is misleading. It is true that if all the dark matter in galaxies spontaneously disappeared, the outer reaches of these galaxies would probably disintegrate. (The central part of the halo, where most of the visible matter is – and indeed where we are – actually contains relatively little dark matter and would be largely unaffected.) But it is not as though dark matter is what keeps galaxies from disintegrating, as they never would have formed in the first place without it! I have tried to revise the article to make this a little clearer. –Joke137 20:48, 9 Jun 2005 (UTC)
Jaan Einasto
What exactly is Jaan Einasto supposed to have done? This page and the article under his name call him "one of the discoverers of dark matter," but there are no more details. According to the article under his name, Einasto has been active in physics long after the dark matter problem was discovered, so it doesn't really make sense as it is. If this claim is true in some sense, it requires some elucidation. -- Reuben 04:00, 20 Jun 2005 (UTC)
I agree. It makes no sense to have a people section without a clear idea of what each person contributed and in which the people seem chosen at random. And while I don't doubt that Einasto has worked on the dark matter problem, his major interest seems to be superclusters and voids: the formation and morphology of structure on the very largest scales. He seems to have contributed quite a bit to this. –Joke137 13:38, 20 Jun 2005 (UTC)