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This seems like another example of what confuses the issue. Joel Send a noteboard - 30/04/2011 05:25:04 PM
The Wikipedia page on MACHOs (MAssive Compact Halo Objects) gives a good summary of the research into non-luminous ordinary matter as a dark matter candidate. It just about universally demonstrates that such objects can only account for a small fraction of all dark matter.

At the bottom of the Wikipedia page is a link to one on RAMBOs, described thus:
In astronomy, a RAMBO or robust association of massive baryonic objects is a dark cluster made of brown dwarfs or white dwarfs.

RAMBOs were proposed by Moore and Silk in 1995. They may have effective radii between 1 and 15 pc, with masses in the range 10–100,000 solar masses.

Dynamics

The dynamics of these objects, if they do exist, must be quite different from that of standard star clusters. With a very narrow mass range (all brown dwarfs or white dwarfs), the evaporation rate of these RAMBOs should be very slow as predicted by the evolution of simulated mono-component cluster models. Theoretically, these very long-lived objects could exist in large numbers. The presence of a clustered thick disk-like component of dark matter in the Galaxy has been suggested by Sanchez-Salcedo (1997, 1999) and Kerins (1997).

So, they're baryonic dark clusters, and the last sentence implies they could account for any dark matter halo around the Milky Way. So now there's yet another new proposal for dark-but-normal matter that could fit the bill without anything more exotic than very distant and/or non-luminous but quite familiar brown and/or white dwarfs.

Meanwhile, I'm not sure how convinced I am by a visual search failing to find extremely faint and distant objects. The theoretical argument is more compelling, but it depends on our current understanding of the Big Bang being correct, and that sems as likely to contain key errors as it is to rule out baryons accounting for all dark matter.

But, yeah, by all means test the theory; you have to, and if it's fully vindicated I'll accept that. Just don't spend so much effort devising more and more tests for a theory that defies proof that you overlook a simpler (and accurate) explanation. ;)
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For completeness, the RAMBO link, though you're probably familiar.
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Exciting video about the universe Camilla - 28/04/2011 10:14:55 AM 1156 Views
Cool, and true *NM* Stephen - 28/04/2011 11:46:29 AM 352 Views
I still think dark matter's just non-luminous matter without a convenient light source to reflect. Joel - 28/04/2011 10:34:21 PM 868 Views
We've just about ruled out the idea that dark matter is just non-luminous "ordinary" matter. Dreaded Anomaly - 28/04/2011 11:44:34 PM 807 Views
I'm aware of the Bullet Cluster, though admittedly not much more than that. Joel - 29/04/2011 01:52:49 AM 742 Views
Re: I'm aware of the Bullet Cluster, though admittedly not much more than that. Dreaded Anomaly - 29/04/2011 02:56:32 AM 846 Views
Re: I'm aware of the Bullet Cluster, though admittedly not much more than that. Joel - 30/04/2011 05:02:49 PM 777 Views
Re: I'm aware of the Bullet Cluster, though admittedly not much more than that. Dreaded Anomaly - 30/04/2011 08:56:35 PM 673 Views
Re: I'm aware of the Bullet Cluster, though admittedly not much more than that. Joel - 02/05/2011 01:28:30 AM 709 Views
Re: I'm aware of the Bullet Cluster, though admittedly not much more than that. Dreaded Anomaly - 04/05/2011 04:18:18 AM 810 Views
There's such a thing as knowing when you're licked, and I believe I am. Joel - 07/05/2011 02:04:53 AM 884 Views
Re: There's such a thing as knowing when you're licked, and I believe I am. Dreaded Anomaly - 09/05/2011 11:28:48 PM 731 Views
Re: There's such a thing as knowing when you're licked, and I believe I am. Joel - 14/05/2011 05:36:45 AM 683 Views
Re: There's such a thing as knowing when you're licked, and I believe I am. Dreaded Anomaly - 17/05/2011 02:09:40 AM 764 Views
Re: There's such a thing as knowing when you're licked, and I believe I am. Joel - 19/05/2011 04:55:21 AM 688 Views
Re: There's such a thing as knowing when you're licked, and I believe I am. Dreaded Anomaly - 24/05/2011 09:32:27 PM 761 Views
The Pati-Salam model was the one I had in mind. Joel - 24/05/2011 10:34:04 PM 702 Views
Re: The Pati-Salam model was the one I had in mind. Dreaded Anomaly - 24/05/2011 11:08:01 PM 922 Views
Re: The Pati-Salam model was the one I had in mind. Joel - 25/05/2011 01:27:10 AM 727 Views
Re: The Pati-Salam model was the one I had in mind. Dreaded Anomaly - 31/05/2011 09:16:18 AM 796 Views
Apologies for the delay; internet's been spotty and I've been busy lately. Joel - 10/06/2011 12:09:04 AM 1047 Views
Re: Apologies for the delay; internet's been spotty and I've been busy lately. Dreaded Anomaly - 14/06/2011 03:38:18 AM 1044 Views
Also, re: lensing from ordinary matter: Dreaded Anomaly - 29/04/2011 05:18:47 AM 744 Views
This seems like another example of what confuses the issue. Joel - 30/04/2011 05:25:04 PM 867 Views
Re: This seems like another example of what confuses the issue. Dreaded Anomaly - 30/04/2011 08:56:40 PM 830 Views
That discussion seems to reduce to "as little new and exotic physics as possible". Joel - 02/05/2011 01:29:03 AM 826 Views
Re: That discussion seems to reduce to "as little new and exotic physics as possible". Dreaded Anomaly - 04/05/2011 04:18:24 AM 792 Views
Re: That discussion seems to reduce to "as little new and exotic physics as possible". Joel - 07/05/2011 02:05:02 AM 958 Views
Re: That discussion seems to reduce to "as little new and exotic physics as possible". Dreaded Anomaly - 09/05/2011 11:29:36 PM 734 Views
Re: That discussion seems to reduce to "as little new and exotic physics as possible". Joel - 14/05/2011 05:35:56 AM 1016 Views
Re: That discussion seems to reduce to "as little new and exotic physics as possible". Dreaded Anomaly - 17/05/2011 02:09:55 AM 632 Views
Re: That discussion seems to reduce to "as little new and exotic physics as possible". Joel - 19/05/2011 02:47:25 AM 976 Views
Re: That discussion seems to reduce to "as little new and exotic physics as possible". Dreaded Anomaly - 24/05/2011 09:46:30 PM 756 Views
Re: That discussion seems to reduce to "as little new and exotic physics as possible". Joel - 25/05/2011 12:20:10 AM 1044 Views
Re: That discussion seems to reduce to "as little new and exotic physics as possible". Dreaded Anomaly - 31/05/2011 09:16:22 AM 857 Views
Re: That discussion seems to reduce to "as little new and exotic physics as possible". Joel - 10/06/2011 12:04:06 AM 1099 Views
Re: That discussion seems to reduce to "as little new and exotic physics as possible". Dreaded Anomaly - 14/06/2011 03:38:12 AM 870 Views
Re: I still think... (apparently, there is a 100 character limit on subjects, and yours was 99) Tor - 28/04/2011 11:57:15 PM 1052 Views
Seems to happen to me a lot; sorry. Joel - 29/04/2011 12:56:14 AM 724 Views
None of this reflects on the actual facts of dark matter. Dreaded Anomaly - 29/04/2011 01:32:52 AM 723 Views
I concede my grasp (or grope) is a somewhat superficial laymans, yes. Joel - 30/04/2011 04:30:28 PM 850 Views
Re: I concede my grasp (or grope) is a somewhat superficial laymans, yes. Dreaded Anomaly - 30/04/2011 08:56:44 PM 670 Views
Re: I concede my grasp (or grope) is a somewhat superficial laymans, yes. Joel - 02/05/2011 01:28:58 AM 1196 Views
Re: I concede my grasp (or grope) is a somewhat superficial laymans, yes. Dreaded Anomaly - 04/05/2011 04:18:27 AM 713 Views
I don't object to changing my mind, but can take more convincing than I really should. Joel - 07/05/2011 02:05:09 AM 921 Views
Re: I don't object to changing my mind, but can take more convincing than I really should. Dreaded Anomaly - 09/05/2011 11:32:17 PM 841 Views
Re: I don't object to changing my mind, but can take more convincing than I really should. Joel - 14/05/2011 05:36:24 AM 1011 Views
Re: I don't object to changing my mind, but can take more convincing than I really should. Dreaded Anomaly - 17/05/2011 02:10:03 AM 750 Views
Re: I don't object to changing my mind, but can take more convincing than I really should. Joel - 19/05/2011 04:33:06 AM 998 Views
Re: I don't object to changing my mind, but can take more convincing than I really should. Dreaded Anomaly - 24/05/2011 09:59:38 PM 748 Views
Re: I don't object to changing my mind, but can take more convincing than I really should. Joel - 24/05/2011 11:19:43 PM 704 Views
Re: I don't object to changing my mind, but can take more convincing than I really should. Dreaded Anomaly - 24/05/2011 11:33:58 PM 665 Views
Re: I don't object to changing my mind, but can take more convincing than I really should. Joel - 25/05/2011 12:55:36 AM 765 Views
Re: I don't object to changing my mind, but can take more convincing than I really should. Dreaded Anomaly - 31/05/2011 09:16:24 AM 711 Views
Re: I don't object to changing my mind, but can take more convincing than I really should. Joel - 10/06/2011 12:09:13 AM 885 Views
Re: I don't object to changing my mind, but can take more convincing than I really should. Dreaded Anomaly - 14/06/2011 03:38:05 AM 848 Views
Might help if you clarified where your skepticism is at Isaac - 29/04/2011 02:32:07 AM 689 Views
Potentially either, or a combination of the two. Joel - 30/04/2011 02:36:50 PM 761 Views
It's hard to discuss without knowing your objections a bit more clearly Isaac - 30/04/2011 04:58:03 PM 670 Views
My primary objection is that alternatives to dark matter seem to have been ruled out prematurely. Joel - 02/05/2011 01:29:14 AM 802 Views
Well, they weren't, not really sure how else to put that Isaac - 10/05/2011 03:19:57 AM 860 Views
Alright then, objection withdrawn (cautious skepticism intact). Joel - 14/05/2011 05:34:17 AM 970 Views
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