From science writer Bruce Dorminey at Forbes:
Time may be running out on the search for the cosmos’ exotic dark matter. Decades after the first searches for dark matter’s hypothetical exotic particle counterparts, researchers are mostly at a loss to explain why there still has been no direct detection. That is, one that could explain why such unseen, dark matter particles only appear to weakly interact with normal matter.
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McGaugh says one huge problem is that while dark matter theory is ‘confirmable’ it is not ‘falsifiable’ as a scientific theory should be.
“There is no clear way to know [that] what you’re looking for — but failing to find — doesn’t exist at all,” said McGaugh. “If you’re convinced it must [exist], you’ll go on looking forever.”
There’s no exit strategy, says McGaugh. Indeed, he says his colleagues have heedlessly blown through many experiential markers which they have chosen to ignore.
“The search for dark matter has become a quagmire of confirmation bias,” McGaugh concludes. More.
So many research areas in science today are hitting hard barriers that it is reasonable to think that we are missing something.
See also: Physicists devise test to find out if dark matter really exists
Largest particle detector draws a blank on dark matter
What if dark matter just doesn’t stick to the rules?
A proposed dark matter solution makes gravity an illusion
and
Proposed dark matter solution: “Gravity is not a fundamental governance of our universe, but a reaction to the makeup of a given environment.”