4 papers
math.DS2025
Classification of abelian actions with globally hypoelliptic orbitwise laplacian I: The Greenfield-Wallach conjecture on nilmanifolds
Sven Sandfeldt
For a action generated by vector fields we define an operator , the orbitwise laplacian. In this paper, we study and…
math.DS2024
Global rigidity for some partially hyperbolic abelian actions with 1-dimensional center
Sven Sandfeldt
We obtain a global rigidity result for abelian partially hyperbolic higher rank actions on certain step nilmanifolds . We show that, under certain natural assumptions, al…
math.DS2024
Centralizer classification and rigidity for some partially hyperbolic toral automorphisms
Sven Sandfeldt
In this paper we consider local centralizer classification and rigidity of some toral automorphisms. In low dimensions we classify up to finite index possible centralizers for volu…
math.DS2024
Partially hyperbolic lattice actions on 2-step nilmanifolds
Homin Lee, Sven Sandfeldt
We prove global rigidity results for actions of higher rank lattices on nilmanifolds containing a partially hyperbolic element. We consider actions of higher rank lattices on tori…