Is there plasma that doesn't radiate visible light? I think the

ZapperZ

And that makes very little sense, because you clearly have not understood what "dark matter" is. If it is a plasma, we would have observed it very clearly. After all, we HAVE observed plasma in other parts of the universe!

You are trying to learn physics in bits and pieces, and I've noticed this in many of your posts on here. I don't think you have a coherent understanding of the physics that you're asking about. This thread is one clear example where you're think you've understood something, when clearly, you missed the complete picture. It is very difficult to comprehend that for someone who didn't know what an "ion" is, that you're are attempting to understand papers like this.

Zz.

Varon

I know what is dark matter.. we don't know what it is composed of.. whether the lightest supersymetric particles or others we don't know. The paper is just proposing it is some kind of plasma and I've been thinking about it for months on and off so may as well ask about plasma here. Btw.. i own over a hundred pop-sci science books and read all of them (mostly mathless hence I focus more on the conceptual as I'm still learning the math) .

Anyway. Here's the abstract of the paper:

"We explore the feasibility and astrophysical consequences of a new long-range U(1) gauge field
(dark electromagnetism") that couples only to dark matter, not to the Standard Model. The
dark matter consists of an equal number of positive and negative charges under the new force,
but annihilations are suppressed if the dark matter mass is sufficiently high and the dark fine structure constant ^ is sufficiently small. The correct relic abundance can be obtained if the dark matter also couples to the conventional weak interactions, and we verify that this is consistent with particle-physics constraints. The primary limit on ^ comes from the demand that the dark matter be eectively collisionless in galactic dynamics, which implies ^ <
10��3 for TeV-scale dark matter. These values are easily compatible with constraints from structure formation and primordial nucleosynthesis. We raise the prospect of interesting new plasma eects in dark matter dynamics, which remain to be explored."

ZapperZ

If you wish to discuss dark matter, then please do so in the appropriate forum.

I have no idea why you would copy the abstract here. It's not as if I can't click a link and read it myself.

This thread is done.

Zz.