Coriolis force (a specious force like centrifugal) results when something, a pressure gradient, forces a fluid to move from the edge of a rotating disk toward the center. In the case of earth's atmosphere, heating at the equator drives circulation toward the poles and the resulting mixing with cool layers moving back toward the equator gives the characteristic cyclone and anticyclone whirls as well as a resonance that is the jet stream. In a galaxy everything is simply rotating in a peculiar gravity field and is not being driven either inward or outward so that specious forces would not operate. Note the lack of cyclones and anticyclones in Venus' atmosphere which parallels the near lack of rotation.
Sounds logical except for the fact literally no one knows what gravity is..
Probably because some think gravity is multi dimensional.. and probably is..
I prefer the "light" energy/matter, "dark" energy/matter mental figment(s) as a metaphorical answer..
WoW!. What do you do for a living?