Not really contradictions, there are those behaviours which you describe (i.e. speeds at the outer regions if galaxies faster than originally expected) and from those we come to things such as dark matter which describe these, but we don’t yet know what they are.
It might be that the theory needs to be changed if there is no such thing as dark matter and it Is jnice calculation trick that actually mean something elsr in the real world, but as of right now it describes most things well.
Alas, there is the disconnect between different theories that don’t work together (see Gravity and Quantum mechanics) or only on different scales
Not really contradictions, there are those behaviours which you describe (i.e. speeds at the outer regions if galaxies faster than originally expected) and from those we come to things such as dark matter which describe these, but we don’t yet know what they are.
It might be that the theory needs to be changed if there is no such thing as dark matter and it Is jnice calculation trick that actually mean something elsr in the real world, but as of right now it describes most things well.
Alas, there is the disconnect between different theories that don’t work together (see Gravity and Quantum mechanics) or only on different scales