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Remove topic that does not discuss the content of the article or sources. Please see WP:NOTFORUM.
 
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{{afd-merged-from|Dark matter in fiction|Dark matter in fiction (2nd nomination)|11 December 2022}}
Removed statement that existence or non-existence of dark matter contradicts big bang. Dark matter actually has very little to do with whether big bang is true or not.
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:The article at [[Big Bang theory]] speaks of a dark matter problem; you may want to correct that if you're better informed than the author. [[User:Mkweise|Mkweise]] 13:05 Feb 16, 2003 (UTC)
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:: Did so. What I suspect that the author was referring to is the fact that dark matter *helps* the big bang theory. During the 1970's, there were a number of problems (mostly deuterium abundances) that have been nicely resolved by assuming that dark matter exists.
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:::I vaguely remember that some time in the 1990s, new observations led to the stunning (at the time) conclusion that more than 90% of the universe's matter is dark. IIRC, some previously favored theories were essentially scrapped due to that - I don't remember specifically what theories, but I think it led to a change in the estimated age of the universe by many orders of magnitude. [[User:Mkweise|Mkweise]] 16:26 Feb 16, 2003 (UTC)
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== Proposal to delete the table "Some dark matter hypotheses" ==
Having a description of Hot Dark Matter there doesn't fit, there should be accompanying descriptions of cold and baryonic.


The table labeled "Some dark matter hypotheses" is puzzling and it's content is not reliably sourced. Rather the categories appear to be invented for the table. The entries are a mix of mainstream candidates and fringe theories. No text helps readers sort out the content. In effect is it an overly long See Also section stuck in the middle of the article. [[User:Johnjbarton|Johnjbarton]] ([[User talk:Johnjbarton|talk]]) 03:16, 24 August 2024 (UTC)
==new content==
The following content was put on the page and was very hard to read. We can try to work it in, but in the meantime I've put it here and reverted the page. --[[User:Zandperl|zandperl]] 01:45, 18 Mar 2004 (UTC)


== Confusing footnote ==
I have just worked it over, chopping it up into paragraphs and also into sections that I think might be better suited to other articles. If nobody objects to what I did with it, I'll merge them into their final destinations tomorrow. [[User:Bryan Derksen|Bryan]] 19:06, 20 Mar 2004 (UTC)


Under "Some dark matter hypotheses" > Neutrinos > Standard Model there is a sourced footnote.
:I just moved all the text to the various articles I'd proposed moving it to (except for the dark energy section, which was entirely redundant with the stuff already in the dark energy article; I just deleted that one). [[User:Bryan Derksen|Bryan]] 06:04, 25 Mar 2004 (UTC)
* The three neutrino types already observed are indeed abundant, and dark, and matter, but their individual masses are almost certainly too tiny to account for more than a small fraction of dark matter, due to limits derived from [[observable universe|large-scale structure]] and high-[[redshift]] galaxies. (ref omitted for Talk page).
As I read this footnote it is an editorial statement that the reference provides evidence against the hypothesis that Standard Model neutrinos account for dark matter (which is what the ref says).


The table gives the impression of (poorly sourced) evidence for a ton different options. If a reader scans the table they conclude "Standard Model neutrinos" are an option. If they read the fine print, they learn it's not an option. To me this is a confusing way to present this information.
I did not see any mention in the article about what portion of dark matter is accounted for by the cumulative relativistic mass of all the photons that have been spewing out of all the stars in all the galaxies for the past several billion years. Should that be added? [[User:David Battle|David Battle]]


@[[User:Banedon|Banedon]] how about starting the Composition section with a paragraph with this content as well as a reminder of the many aspects of the Standard Model which fail to make the cut for simpler reasons. The latter may seem simplistic but I think it would set up the far ranging search implied by the table. [[User:Johnjbarton|Johnjbarton]] ([[User talk:Johnjbarton|talk]]) 03:16, 8 October 2024 (UTC)
:Photons don't have any rest mass, and we usually just talk about "energy" instead of "relativistic mass." The energy of the photons goes into the energy budget of the universe as radiation, not dark matter - because you can see them. [[User:Reuben|reuben]]
:Well, the table also has "MACHO" even though that's been ruled out too. Feel free to make your changes, I'm not likely to revert. [[User:Banedon|Banedon]] ([[User talk:Banedon|talk]]) 04:11, 8 October 2024 (UTC)

Latest revision as of 16:27, 14 December 2024

Former good articleDark matter was one of the Natural sciences good articles, but it has been removed from the list. There are suggestions below for improving the article to meet the good article criteria. Once these issues have been addressed, the article can be renominated. Editors may also seek a reassessment of the decision if they believe there was a mistake.
Article milestones
DateProcessResult
April 4, 2006Peer reviewReviewed
January 28, 2007Good article nomineeListed
July 11, 2009Good article reassessmentDelisted
Current status: Delisted good article


Proposal to delete the table "Some dark matter hypotheses"

[edit]

The table labeled "Some dark matter hypotheses" is puzzling and it's content is not reliably sourced. Rather the categories appear to be invented for the table. The entries are a mix of mainstream candidates and fringe theories. No text helps readers sort out the content. In effect is it an overly long See Also section stuck in the middle of the article. Johnjbarton (talk) 03:16, 24 August 2024 (UTC)[reply]

Confusing footnote

[edit]

Under "Some dark matter hypotheses" > Neutrinos > Standard Model there is a sourced footnote.

  • The three neutrino types already observed are indeed abundant, and dark, and matter, but their individual masses are almost certainly too tiny to account for more than a small fraction of dark matter, due to limits derived from large-scale structure and high-redshift galaxies. (ref omitted for Talk page).

As I read this footnote it is an editorial statement that the reference provides evidence against the hypothesis that Standard Model neutrinos account for dark matter (which is what the ref says).

The table gives the impression of (poorly sourced) evidence for a ton different options. If a reader scans the table they conclude "Standard Model neutrinos" are an option. If they read the fine print, they learn it's not an option. To me this is a confusing way to present this information.

@Banedon how about starting the Composition section with a paragraph with this content as well as a reminder of the many aspects of the Standard Model which fail to make the cut for simpler reasons. The latter may seem simplistic but I think it would set up the far ranging search implied by the table. Johnjbarton (talk) 03:16, 8 October 2024 (UTC)[reply]

Well, the table also has "MACHO" even though that's been ruled out too. Feel free to make your changes, I'm not likely to revert. Banedon (talk) 04:11, 8 October 2024 (UTC)[reply]
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