Universal Scaling Function of Velocity Rotation in Spiral galaxies
  The data of velocity rotation curve in spiral galaxies, almost for galaxies which have close central surface brightness, collapse onto a universal scaling function. Since scaling functions are the signature of emergence in complex systems we are led to the idea that explanation of constant velocity in spiral galaxies needs considering cooperative behavior instead of interpretation based on reductionism approach. 
Reza Torabi
astro-ph.GA