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View Full Version : Could dark matter be made up of slow neutrios?



WaxRubiks
2010-Apr-02, 05:18 PM
I wondered if dark matter could be made up of neutrinos that were created in the big bang and weren't moving very fast.

There would have to be a lot of them, I know.



ETA: yes I got the title wrong...

korjik
2010-Apr-02, 05:31 PM
IIRC, it would require too many neutrinos. Something like a few orders of magnitude more than could be explained.

Cougar
2010-Apr-03, 01:50 PM
IIRC, it would require too many neutrinos. Something like a few orders of magnitude more than could be explained.

I'd agree. There are a heck of a lot of neutrinos, but they don't have enough mass, and they're not slow.

Cheap Astronomy
2010-Apr-04, 08:11 AM
Neutrinos are the 'dark matter particle' of the hot dark matter theory (http://en.wikipedia.org/wiki/Hot_dark_matter) - albeit this theory is largely out of favour in current thinking (which favours the cold dark matter, neutralino based, theory). I did a 365 days podcast (http://365daysofastronomy.org/2010/03/23/march-23rd-what-can-the-dark-matter-be/) which touches on this - if of interest.

Steve