non-Keplerian orbits and dork matter

F=Ma

where a generated by central force field
gives Keplers Laws for motion of stars in
gavitational field of galaxy.

But assumes that M is constant.

In fact dM/dt 0

due to mass loss from stellar populations
this coupled with asymmetric gas distribution
due to outflow from center of galaxy yields
non-Keplerian orbits

No dork matter needed