Scale Interactions and Galaxy Evolution
  To understand galaxies and their evolution, it is necessary to describe how the different scales interact: how the microscopic physics, such as star formation, or the large scale physics, such as galaxy interactions may modify the galaxy global shapes. The purpose of this review is to point out some general or recent topics related to such scale interactions, both observational and theoretical, which are relevant in the present understanding of galaxies. 
Daniel Pfenniger (University of Geneva, Geneva Observatory)