No, actually scientists don't know this. And maybe that is a clue why this ...Scientists Uncover New Physics in the Search for Dark Matter
No, scientists still have no idea what dark matter is. However, MSU scientists helped discover new physics while searching for it.
Wolfgang “Wolfi” Mittig and Yassid Ayyad began their search for dark matter—also referred to as the missing mass of the universe—in the heart of an atom around three years ago.
Even though their exploration did not uncover dark matter, the scientists nonetheless discovered something that had never been seen before that defied explanation. Well, at least an explanation on which everyone could agree.
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Dark matter is one of the most well-known yet least understood things in the universe. Scientists have known for decades that the universe contains more mass than we can perceive based on the motions of stars and galaxies.
... is true.Speaking in round numbers, scientists have launched about 100 experiments to try to illuminate what exactly dark matter is, Mittig said.
“None of them has succeeded after 20, 30, 40 years of research,” he said.
But at least this experiment yielded something that may be of use. What, I've no idea ... and I'm not sure they do either.