New study sows doubt about "dark energy".
"Dark energy" is a hypothetical explanation for the accelerating expansion of our Universe. Scientists in Copenhagen have demonstrated that it's an unnecessary concept, if the "dark matter" that is gravitationally influencing the motions of galaxies (despite being invisible so far) possesses magnetic energy too.
https://www.sciencedaily.com/releases/2021/03/210331103624.htm
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The universe expands no differently without dark energy:
The usual understanding of how the universe's energy is distributed is that it consists of five percent normal matter, 25 percent dark matter and 70 percent dark energy.
In the UCPH researchers' new model, the 25 percent share of dark matter is accorded special qualities that make the 70 percent of dark energy redundant.
"We don't know much about dark matter other than that it is a heavy and slow particle. But then we wondered -- what if dark matter had some quality that was analogous to magnetism in it? We know that as normal particles move around, they create magnetism. And, magnets attract or repel other magnets -- so what if that's what's going on in the universe? That this constant expansion of dark matter is occurring thanks to some sort of magnetic force?" asks Steen Hansen.
Computer model tests dark matter with a type of magnetic energy:
Hansen's question served as the foundation for the new computer model, where researchers included everything that they know about the universe -- including gravity, the speed of the universe's expansion and X, the unknown force that expands the universe.
"We developed a model that worked from the assumption that dark matter particles have a type of magnetic force and investigated what effect this force would have on the universe. It turns out that it would have exactly the same effect on the speed of the university's expansion as we know from dark energy," explains Steen Hansen.
However, there remains much about this mechanism that has yet to be understood by the researchers.
And it all needs to be checked in better models that take more factors into consideration. As Hansen puts it:
"Honestly, our discovery may just be a coincidence. But if it isn't, it is truly incredible. It would change our understanding of the universe's composition and why it is expanding. As far as our current knowledge, our ideas about dark matter with a type of magnetic force and the idea about dark energy are equally wild. Only more detailed observations will determine which of these models is the more realistic. So, it will be incredibly exciting to retest our result.
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ALSO...
The following might be completely unrelated, but magnetic monopoles have also never been observed despite how they're often predicted in theoretical models. The models usually predict that they'd be extremely massive particles, so massive that we could never create them from the energies released during particle collisions. They would be created during the Big Bang, and then persist thereafter, but we have little hope of ever recreating such incredible energies.
Magnetic monopoles would be particles with magnetic charge, like an electron with electrical charge. As of now, magnetic fields have only been observed as dipoles (with north and south poles) arising fundamentally from electrical charges. But many physicists believe that fundamental particles associated with magnetic charge should also exist.
https://royalsocietypublishing.org/doi/10.1098/rsta.2011.0394
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An even simpler bound is due to the total mass of the monopoles in the universe. From astronomical observations [12], we know that matter particles make up approximately 23 per cent of the total energy in the universe, and roughly one-third of this can be accounted for by known particles. In principle, some or all of the remaining dark matter could be magnetic monopoles. If they are light enough, Inline Formula, they are not gravitationally bound to galaxies, and one can approximate that they are roughly uniformly distributed in the universe. From the observed dark matter density, one obtains an upper bound
(Display Formula
3.2)
where v is the average speed of the monopoles. Because of the mass dependence, this bound is only relevant for heavy monopoles, such as GUT ones.
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The idea was also mentioned here, in 2019:
Dark Monopoles: Theoretical Physicists Propose New Candidate for Dark Matter
http://www.sci-news.com/physics/dark-monopoles-07286.html
= new reply since forum marked as read
... over the last 40+ years or so, but I know what you mean.
If I bring it up to some people, I usually have to keep reminding myself that some of the concepts are alien to them.
But my kind of "big picture" dabbling won't do much good. It's the actual experts, who indeed think and work on this stuff every day, that might clear up the mysteries someday. I'm mostly just a fan, like a rock star groupie or something. 
