Physics only tells us that galaxies don't move the way we think they should.
There are two explanations: there is extra mass in galactic systems that we can't detect, or our understanding of gravity is more incorrect than previously thought.
When you dig in, there's a small amount of evidence that suggests there is extra mass, but also we can modify our equations of gravity to produce similar results.
Dark matter and MOND (one of the leading alternate gravity models) both have compelling cases for them, and both show exceptions that don't match observed data.
I genuinely don't understand why people push dark matter, as a solution it's way too complex for the problem it solves. It makes more sense that our model of gravity (which we know is already incomplete) is more incomplete than it does for there to be an entire class of matter that we can't detect or even construct meaningful theories about.
I've yet to encounter a speaker or article that just stated there is an observation they can't explain. They all talk about some theory or theories to try to explain things.
But that's not science. It takes a discernible reader to learn about this topic, and they should be able to distinguish between science and popular science which enjoys speculating. I think both are interesting and important in educating the public.
That's how science works. There's a mystery and science purposes a hypothesis resolving that mystery. If a hypothesis is clearly more consistent with the evidence then other hypothesises, it wins out. If not, there continues to be a debate.
My point is that people aren't sticking to tested ideas when communicating with the public. They're throwing untested ideas at them, or sometimes multiple incompatible untested ideas at them.
And so? Are the 'science police' going to show up an arrest them?
There is a reason that scientists communicate with other scientists via papers and a process called peer review and not typically via the media. That is, to distill the topic down to a casual level requires many levels of abstraction and tend to be 'incorrect but interesting' as the media does not sell truth, but instead it sells advertising by making things interesting.
There are two explanations: there is extra mass in galactic systems that we can't detect, or our understanding of gravity is more incorrect than previously thought.
When you dig in, there's a small amount of evidence that suggests there is extra mass, but also we can modify our equations of gravity to produce similar results.
Dark matter and MOND (one of the leading alternate gravity models) both have compelling cases for them, and both show exceptions that don't match observed data.
I genuinely don't understand why people push dark matter, as a solution it's way too complex for the problem it solves. It makes more sense that our model of gravity (which we know is already incomplete) is more incomplete than it does for there to be an entire class of matter that we can't detect or even construct meaningful theories about.