Yes, science was, sort off, forced to accept dark matter when the ASSUMED universal laws of celestial motions around a gravity center was contradicted in galaxies. But instead of revising the laws, science ASSUMED dark matter "to hold the stars inside galaxies" because they otherwise would fly away from the galaxies because of the "abnormal motions".
Standard science failed to analyse the galactic formation and the motions of the stars, and they simply inserted an ASSUMED dark matter in order to fit the starry motions to their former and contradicted equations.
And, as this new ASSUMED dark invention again fits the old (contradicted) equations, they took dark matter to exist as a "conclusive evidence".
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Of course cosmological science ASSUMES. This is the very basics in all science. They just call it "new theories".
There are still a lot to know that we don’t know about, outside of our Solar System.
Some we have learned through discoveries of evidence, and they have become “scientific theory”.
While others are just proposals, models that are still hypothetical (a hypothesis) or theoretical, yet to be tested, or currently undergoing testing.
Example: both are proposed explanation, or draft, that haven’t been accepted or rejected. For that reasons, neither hypotheses, nor theoretical models, have the status of “scientific theory”.
Scientific theory must meet the following requirements:
- being FALSIFIABLE,
- have been TESTED (and analyzed) in Scientific Method, eg observation through evidence or through experiments,
- and have been REVIEWED by PEERS (eg Peer Review)
A hypothesis should at least passed being “falsifiable”. If the hypothesis can come up with ways to possibly test the explanation, equations/formulas and predictions, then it is falsifiable, regardless if the evidence are positive or negative.
A theoretical model is explanation with some sorts of complex equations or formulas being solved, but haven’t been tested.
To put in another way, a theoretical model offer a proposed explanation that are mathematically possible, but not yet tested and accepted.
As to the dark matter and dark energy.
Well, it has been tested, if not directly observed. As others have pointed out to you, they have indirectly observed through the gravitational effect on the motion of galaxies and other objects.
And that it these effects can be MEASURED (from the WMAP & the Planck missions), make the dark energy and dark matter, at the very least falsifiable, and partially tested.
It is no longer just assumptions, Native.
Don’t get me wrong, Native. There are still more to be learned, more to investigate, more to test for both dark matter and dark energy. The works are done yet, but there are far more promising leads than the mythological creation from whatever scriptures you believe in.
The only person making assumptions is you, in your reply.
If you have better alternative explanation, like where those masses are coming from, if not from dark matter or if didn’t come from dark energy, then you are the one is assuming, without evidence.
But I question this very much.
