Unraveling
\[A_g\]
with the aid of Group Actions

Anita Rojas
Universidad de Chile (Chile)
Abstract:
The study of the moduli space of abelian varieties
\[A_g\]
, has been one of the key topics in Herbert Lange's mathematical life. His books and papers are fundamental references on the field.
On the other hand, several Chilean geometers have been working on group actions on varieties for a long time: researching, organizing conferences, and training students on this subject.
The combination of these different areas of expertise was natural and has been fruitful. 
The collaboration between Herbert Lange and the Chilean mathematical community has been deep and has spanned decades, not only being limited to research, but has also extended to co-organizing international meetings, collaboration in forming students, etc.  
In this talk we will try to present part of this extensive and profound collaboration, both in mathematics and its surroundings, presenting that which has been important to the community of Chilean geometers.