The best evidence is the need for dark matter in the Big Bang. The big split does not require any made up substance in order for the acceleration of the bodies. Like any hypothesis the best place to start would be what are the short comings of the idea of a Universal Vortex?
The biggest obstical is its Geometry as has been pointed out on this site. I know there are vortex geometry studies out there, but their focus hasn't much to do with cosmology. One of the biggest obsticles in the geometry is how after the "Big Split" the split stopped. I have mentioned electromagnetism as a possibility, but this would cause a system that would create two separate "universes". The first would be at the center of the initial split and the other would be at the edges where the "wrap around" occurred. This makes the geometry extremely difficult. Or I could take the approach that the edges never closed and continue to split eternally and the vortex will continue to grow infinately, a sorta evolving Meta Model.
So there are far more questions than answers at this point. But, I enjoy the quest tremendously.
