The vortex model of 1944, formulated by the German physicist and philosopher Carl Friedrich von Weizsäcker, hearkens back to the Cartesian model by involving a pattern of turbulence-induced eddies in a Laplacian nebular disc. In Weizsäcker's model, a combination of the clockwise rotation of each vortex and the anti-clockwise rotation of the whole system could lead to individual elements moving around the central mass in Keplerian orbits, reducing energy dissipation due to overall motion. However, material would be colliding at a high relative velocity in the inter-vortex boundaries and, in these regions, small roller-bearing eddies would coalesce to give annular condensations. This hypothesis was much criticized, as turbulence is a phenomenon associated with disorder and would not spontaneously produce the highly ordered structure required by the hypothesis. It also does not provide a solution to the angular momentum problem or explain lunar formation and other very basic characteristics of the Solar System.