My dark matter prediction

[Realitycheck]

I'm going to make a prediction that dark matter is repulsive to ordinary matter, like two magnets pushing against each other, just as dark energy pushes space apart. Maybe the reason why universal expansion has sped up is because there is more non-baryonic matter compared to normal matter. We already have this mysterious phenomenon called gravity that we know so much about. Why does gravity even occur, and then maybe there is an opposing force to it, antigravity, or a cosmological constant, maybe its due to the existence of this excess proportion of non-baryonic matter, though maybe dark matter is immune to the antigravity of other dark matter. This could easily explain why there is no dark matter anywhere near our planet, and it really appears to be more apt to exist out in free space. Of course, it is entirely possible that the two phenomena, dark energy and dark matter have no relationship to each other whatsoever, but maybe.

Edited May 21, 2011 by Realitycheck

[Bignose]

A major reason we think that there is matter out there is because unless there is more matter than we can see -- this ubiquitous dark matter -- that significant parts of the universe aren't obeying the law of gravity as we know it today. There are even maps of the dark matter, when its presence can be inferred by its gravity effects. See http://www.space.com/3319-astronomers-create-3d-map-dark-matter.html It certainly is possible that our understanding of gravity is wrong. For sure, our understanding of gravity is incomplete. But, I'm not sure that there is much to suggest that dark matter would be repulsive. Even anti-matter still obeys the known gravity laws.

 

Would you be able to do the work to attempt to make a "repulsive dark matter" map analogous to the dark matter map above? That is, if dark matter really were repulsive, if you put repulsive forces into the models, can you make the models replicate known observations?

[Janus]

Of course, it is entirely possible that the two phenomena, dark energy and dark matter have no relationship to each other whatsoever, but maybe.

 

It is not only possible, it is most undoubtedly true. The only thing they have in common is the word "dark" in their names. The "dark" in dark matter stands for the fact that it does not emit or react with light. The "dark" in dark energy merely comes from the fact that we already had something called dark matter, so it seemed fitting to reuse the label "dark" for what ever was causing the accelerated expansion of the universe.

 

As far as dark matter being repulsive to baryonic matter, this would be in direct contradiction to what dark matter is supposed to explain, which is why galaxies spin much faster and with different rotation curves then they would if just the gravity of baryonic matter holding them together.

 

The reason there is little to no DM near the Earth is that even though the galaxy has much more DM than baryonic matter, DM is spread out over a much larger volume and thus has a lower overall density than the baryonic matter which is mostly constrained to the visible galactic disk. If you then add in the fact that the mass distribution of the solar system is in turn much much more dense than that of the visible disk overall, the amount of DM that you would expect to find in the whole of the Solar system works out to be the equivalent of a small moon. Since DM does not clump together the way that Baryonic matter does, this would be spread throughout the solar system. 3.

[Realitycheck]

Come to think of it, the halos probably tend to follow the galaxies around. What was I thinking? I was really just thinking out loud and throwing some ideas out there. Thank you for the enlightening responses though.