I’m not a subscriber to this particular theory, but I do think model error is a more plausible explanation than magical, undetectable mass.
The mass is definitely detectable–it’s just not visible. And it’s detectable in several different ways that all match, that’s the key here. This is definitely an observation.
Dark matter is an infinite number of free variables we can place anywhere in our universe to make our current gravitational models work. Of course they match.
Can you call it an observation if the lens you are using may be faulty?
Why is dark matter given so much precedence over model error? (Particularly because we know our current model can’t do things like quantum gravity)
Can you call it an observation if the lens you are using may be faulty?
If you use many lenses you can assure yourself that they are not all faulty in the same way. This is why we can safely say that dark matter is observed fact, because we observe it in so many different ways.
