Abstract
The IMF for stars more massive than a few solar masses appears to be a universal function that can be well approximated by a power-law of slope surprisingly close to the value found by Salpeter 50 years ago. We use the central cluster of 30 Doradus to determine an accurate value for the IMF slope, and we show that the few seriously discrepant IMF's reported in the literature are most likely due to systematics in the data processing. We propose that massive star formation shows this surprising regularity over a wide range of physical parameters because it is regulated by the laws of complexity. More precisely, we propose that the ISM is in a state of Self-Organized Criticality (SOC) which is a transition between order and chaos.
