If you read the article it describes how physicists modeled "dark matter stars" in the early universe. Problem? It's all fricking conjecture.
No one has ever directly observed any dark matter. They think they have observed its effects on some galactic structures billions of lightyears from here, and they think that dark matter is responsible for certain properties which galaxies have. The latter case may be explainable using General Relativity rather than classic mechanics, though, so in fact there is no real hard evidence supporting the existence of dark matter.
And so it goes without saying that no one knows what it's made of.
But dark matter stars may have "lit" the early universe. Dark matter interacts too weakly for us to directly observe it, but apparently it does not interact weakly with antimatter? Do I understand this?
"In order to model the dark matter stars, the physicists needed to decide on a dark matter particle model. Since this is still a wide-open issue in physics...," (Emphasis mine.) The emphasized phrase is a polite way of saying, "Nobody has a fucking clue about this." Okay?
This study is essentially worthless. The people involved started with a premise, made up some numbers that would make it possible, and are now attempting to test their "theory" against observations. Odds are about even that they'll find some phenomenon which matches their criteria to maybe ten percent or so, which is close enough for a first approximation. And they may even then be able to refine their theory to better fit the observations.
But it doesn't prove the existence of dark matter. By definition the stuff interacts so weakly that we cannot see it even though it supposedly is 90% of the mass in the universe.
In the early years of the 20th century, physics still clung to the idea of the "luminiferous ether". It was a fluid which filled the entire universe; it was the medium in which electromagnetic waves propagated--like waves in water--and it had certain properties:
1) Zero viscosity; it did not slow the planets in their orbits or blow off the Earth's atmosphere, yet it permeated the atmosphere completely
2) Perfectly transparent: it had no index of refraction
3) Zero mass, zero inertia
4) ubiquitous: it was everywhere
...of course, it turned out that there's no such thing as the luminiferous ether. Michaelson and Morely built an interferometer which was meant to test for the existence of the ether, and it failed to detect anything at all.
They failed to detect it because it didn't exist; light doesn't need a medium in which to propagate because light is photons, and the wavelike nature of light comes from the ways in which photons interact.
I think that "dark matter" is much the same sort of thing. It's a notion cooked up to "fix" problems with certain theories; and as time goes on it has grown warts and fangs and other features, as needed, in order to satisfy this or that requirement.
And now we find that dark matter--which interacts so weakly with normal matter that we have to infer its existence from the ways in which galactic-scale events play out--interacts strongly enough with antimatter that such reactions fueled pseudo-stellar objects in the earliest eons of the universe.
That makes no freaking sense.
Even assuming that antimatter was then present in much greater quantities than it now is, it still could only have been 5% of the mass (50% of 10%, since 90% of the universe is supposedly dark matter) of the universe at the time. And the composition of the "dark stars" was supposedly 85% dark matter and 15% baryonic matter--meaning that a mere 7.5% of the matter in them was antimatter, assuming symmetrical distribution of matter and antimatter.
I don't buy it. And I don't see how anyone can take this theory seriously when it's starting with, "Well, we took a wild-ass guess about what dark matter particles are...."
And to make matters even worse, it's a question nobody asked. There is nothing wrong with early stars being regular fusion-style stars. There was nothing but hydrogen in the early universe, and if dark matter is such a weakly-interacting form of matter it shouldn't have been an issue before there were galaxies. The only thing this theory does is explain what happened to most of the antimatter in the universe--and there are other theories explaining it that at least don't require a belief in the boogey-man in order to work.
I have a feeling that about the time that physics is congratulating itself on figuring all this crap out, someone's going to come along with a theory that explains everything simply and which makes all this "dark matter/dark energy" BS utterly worthless. I hope I'm around (and sane enough) to see it, 'cause I am going to laugh....