3 papers
math.DG2024
Dirac eigenvalues and the hyperspherical radius
Christian Baer
For closed connected Riemannian spin manifolds an upper estimate of the smallest eigenvalue of the Dirac operator in terms of the hyperspherical radius is proved. When combined wit…
math.DG2024
First-order elliptic boundary value problems on manifolds with non-compact boundary
Christian Baer, Lashi Bandara
We consider first-order elliptic differential operators acting on vector bundles over smooth manifolds with smooth boundary, which is permitted to be noncompact. Under very mild as…
math.DG2023
K-cowaist of manifolds with boundary
Christian Baer, Bernhard Hanke
We extend the K-cowaist inequality to generalized Dirac operators in the sense of Gromov and Lawson and study applications to manifolds with boundary.