CompPhys17 is the 18th International NTZ-Workshop on New Developments in Computational Physics On Dec. 1, 2017 David P. Landau, Distinguished Research Professor of Physics and Director of the Center for Simulational Physics, presented the Keynote Invited Lecture at CompPhys17, The 18th International NTZ-Workshop on New Developments in Computational Physics. The title of his presentation was “Complexity and Optimization: Physical Science Meets Biological Science via Computer Simulations”. The meeting, held in Leipzig, Germany, drew participants from throughout Europe, the U.S., Asia, and Australia.