11#11 can be derived from simple arguments about stars on the Hayashi track. The potential energy given off by stars on this track is 12#12, while the stellar luminosity 13#13. Since the stellar luminosity is the change in energy per unit time, 14#14. Along the convective tracks, temperature is approximately constant. Removing all the constants one gets 15#15. Integrating leads to 16#16.

Scott J. Wolk
Wed Dec 4 18:01:50 EST 1996