One alternative is 'Process Physics' which is not widely accepted but has a fundamentally different explanation for dark matter: Turbulence in the in-flow of sp

One alternative is 'Process Physics' which is not widely accepted but has a fundamentally different explanation for dark matter: Turbulence in the in-flow of space into matter. This flow is PP's model for gravity itself, as if matter continuously 'consumes' space to continue its existence. It's an interesting, quite different and generally totally rejected point of view.