When I was taking an astronomy class I thought they were assuming some other ridiculous things as well. The biggest one is the expansion of the universe. They plot a few data points a few years apart and then extrapolate the information for billions of years. It's foolish.
Everything is cyclical. The universe won't expand forever. Even the naming convention dark-matter implies that the unknown thing is matter... when really it is unknown gravity. Why wouldn't you call it what it is? It's dark-gravity. We assume the unknown gravity comes from matter but we really don't know anything about gravity to begin with.
It's all very odd.
A few billion years apart. Since the speed of light in a vacuum is limited we can actually look into to past. All the way back to the moment the Universe cooled down enough for protons to catch elections to form the first hydrogens atom and the universe became transparent.
You don't see how that is also gross extrapolation prone to heinous errors? We are calculating derivatives while traveling on a curve. We are bending curves into straight lines because the straight lines make the math work. Great, it works. It is also wrong.
I'm sure that those who wrote the papers did make an error examination as no paper will pass peer review without. You know that magic 5σ thing the physics guys are always on about.
Physics isn't feminism where everything passes peer review without questioning.
They are even assuming its gravity.
I prefer large/small galactic force.
That would make three sets of push/pull forces.
The galaxy spins as if all the stars were glued to a plate.
The outer stars move much faster than the inner stars.
Gravity just doesn't explain that at all.
Electric Universe!
I would agree, however, we don't know much about electricity or energy.
large/small galactic force
large/small electric force
large/small nuclear force
I do not believe its electric and magnetic forces.
electric, magnetic, gravetic are all the same force in different directions.
Speaking of “galactic force” PBS one something similar just this week. The presenter doesn't quite like the idea but you might: