2020/05/07 by Baldi, Gregorio, Ullmo, Emmanuel · 3 citations
#Algebraic Geometry (math.AG) #FOS: Mathematics #Group Theory (math.GR)
paper · doi:10.48550/arxiv.2005.03524
Let Γ⊂ PU(1,n) be a lattice, and SΓ the associated ball quotient. We prove that, if SΓ contains infinitely many maximal totally geodesic subvarieties, then Γ is arithmetic. We also prove an Ax-Schanuel Conjecture for SΓ, similar to the one recently proven by Mok, Pila and Tsimerman. One of the main ingredients in the proofs is to realise SΓ inside a period domain for polarised integral variations of Hodge structures and interpret totally geodesic subvarieties as unlikely intersections.