Dark matter chemistry?

[Xyph]

How much does the particulate form of dark matter (WIMPs, supersymmetric particles, etc) actually interact? Could dark matter have some sort of analog to baryonic atoms and chemistry?

 

Also, what relation is dark matter generally considered to have to dark energy? In the case that they are linked, somehow, what sort of relationship would this be? Would dark energy be a weak force like gravity, only apparent when dark matter accumulates in high enough concentrations, or could it be a more specific relationship, such as the byproduct of a "dark EM" of some kind?

[insane_alien]

we don't actually know what dark matter is yet so we cannot describe the chemistry of them. but i would assume that what ever the stuff is it would be inert since it doesn't interact

[Xyph]

I know we don't know exactly what dark matter is yet, but I assume there are some models which would describe potential interactions... Even if it doesn't interact with baryonic matter, I would think it might have some sort of interactions amongst itself.

[timo]

The interaction with other matter (or itself) would depend on what dark matter is. For the two classes of candidates you mentioned, the interactions are pretty much described by their names already. If it´s WIMPs, then they´d interact via the weak force. If it´s SUSY particles then they´d mostly have the same interactions as the particle they are the SUSY partner of.

 

EDIT: And to elaborate on the 2nd part of your original question a bit more: I do not think dark matter and dark energy are related. They enter theory for different reasons and -which would be the more important point- unless I´m mistaken here they also do have different properties. Dark energy is the attempt to map a constant (called "Cosmological Constant") that may appear in the Einstein Equations on a physical object. Dark matter is needed if the Einstein Equations are correct - regardless of the quantity of the Cosmological Constant.

[Xyph]

If it´s SUSY particles then they´d mostly have the same interactions as the particle they are the SUSY partner of.

They would? Doesn't that mean you could get supersymmetric atoms, and the like? In fact, if that's the case, what's to stop the formation of masses of supersymmetric galaxies, with a complexity rivalling their baryonic counterparts? (Except lacking interactions involving electromagnetic radiation, presumably).

[Severian]

They would? Doesn't that mean you could get supersymmetric atoms, and the like? In fact, if that's the case, what's to stop the formation of masses of supersymmetric galaxies, with a complexity rivalling their baryonic counterparts? (Except lacking interactions involving electromagnetic radiation, presumably).

 

They have different spin and are much heavier, so this wouldn't happen. In fact, the interactions look rather different when you include the kinematics - what Atheist meant (I think) was that they couple to the same particles as their SM partners, with related strengths. So for example, they have the same electromagnetic interactions (so I don't understand your last comment).

 

Also, only the lightest SUSY particle is stable. This is probably a neutralino, which is a mixture of the SUSY partners of the Higgs boson and the photon. We don't see universes built out of Higgs bosons and photons do we...?

[Xyph]

Ahh - my comment that they wouldn't interact electromagnetically was because I had assumed that they could make up a significant amount of the dark matter content of the universe, and so would be dark... Thanks for explaining.

[Severian]

Ahh - my comment that they wouldn't interact electromagnetically was because I had assumed that they could make up a significant amount of the dark matter content of the universe, and so would be dark... Thanks for explaining.

 

Ah - I see what you mean. Yes, you are right - dark matter can't be charged. This is actually a constraint on SUSY models because quite often the lightest SUSY particle of a model is a stau, the SUSY partner of a tau, which is charged.

[timo]

Actually, it might be that I was wrong about the WIMP part. I read one or two papers today in which WIMP refered to particles with little interaction - not nessecarily particles with weak interaction only.