I Is Dark Matter Composed of Low-Mass Particles?

AI Thread Summary
The discussion centers on whether the diffused distribution of dark matter as halos over galaxies indicates that it is composed of low-mass particles, concluding that it does not. It notes that if dark matter particles are "collisionless," there are minimal constraints on their mass. While a "thermal freeze out" model suggests a relationship between mass and mean-velocity, it is deemed unlikely that dark matter fits this model. Consequently, there are no strong limits on dark matter mass, with candidate theories proposing masses ranging from 10-26 GeV to asteroid mass. Overall, the composition of dark matter remains uncertain, with various theories still under consideration.
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Does the diffused distribution of dark matter as halos over galaxies imply dark matter is made up of low-mass particles?
 
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No.

Assuming, that dark matter particles are "collisionless" there is very little constraint regarding particle mass.

For a "thermal freeze out" sub-type of dark matter there is a viral relationship between mass and mean-velocity of dark matter, this puts a lower and upper bound on dark matter mass from the extent of large scale structure in this scenario. But, there is no likelihood that dark matter is "thermal freeze out" dark matter.

But, in the general case there are not strong limits. Dark matter candidate papers range from candidates with 10-26 GeV and up to at least asteroid mass.
 
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