View Single Post
  #32 (permalink)  
Old 06-October-2005, 12:20 PM
dgruss23's Avatar
dgruss23 dgruss23 is offline
Senior Member
 
Join Date: Dec 2002
Location: Upstate New York
Posts: 4,216
Default

Quote:
Originally Posted by Robert A.
However, there is not enough of this matter (not to mention it is baryonic, and the evidence - abundances of deuterium and Lithium-7 - is that most dark matter is nonbaryonic) to account for the rotation curves we see in spiral and elliptical galaxies.
Unfortunately, the standard collisionless CDM has problems . It is helpful to remember that the notion that the DM must be non-baryonic is not a direct observational result, but rather the result of plugging observations into the standard model. Those observations are telling us that either the DM is non-baryonic or the standard model needs adjustment. Both options must be kept open.

Quote:
After all that, the bottom line is that the largest component of dark matter - the nonbaryonic flavor - has not been detected.
Not yet. Certainly the coupling of visible and dark matter suggests the proposed non-baryonic candidates may not have the right properties.

Quote:
I, for one, am glad that there are major mysteries in astronomy. If we really did know it all, there would be no surprises, and it would get boring mighty fast.
Ditto
__________________
"The scientist who asks the right question reconnoiters a new patch of the unknown, and may, with luck, bring it within the constricted but expanding boundaries of the known."

~Timothy Ferris (The Red Limit) 1982
Reply With Quote