GL+(2, ℝ)–orbits in Prym eigenform loci

Erwan Lanneau, Duc-Manh Nguyen
2016 Geometry and Topology  
This paper is devoted to the classification of GL^+(2,R)-orbit closures of surfaces in the intersection of the Prym eigenform locus with various strata of quadratic differentials. We show that the following dichotomy holds: an orbit is either closed or dense in a connected component of the Prym eigenform locus. The proof uses several topological properties of Prym eigenforms, which are proved by the authors in a previous work. In particular the tools and the proof are independent of the recent
more » ... esults of Eskin-Mirzakhani-Mohammadi. As an application we obtain a finiteness result for the number of closed GL^+(2,R)-orbits (not necessarily primitive) in the Prym eigenform locus Prym_D(2,2) for any fixed D that is not a square.
doi:10.2140/gt.2016.20.1359 fatcat:bblzgrazerh6dmujafuhrs4w5a