arXiv subjects

Timon Weinmann

Publications and source records attributed to Timon Weinmann.

2 recordsLinked to original sources

arXiv2023

Lieb--Thirring inequalities on manifolds with constant negative curvature

In this short note we prove Lieb--Thirring inequalities on manifolds with negative constant curvature. The discrete spectrum appears below the continuous spectrum $(d-1)^2/4, \infty)$, where $d$ is the dimension of the hyperbolic space. As an application we obtain a P\'olya type inequality with not a sharp constant. An example of a 2D domain is given for which numerical calculations suggest that the P\'olya inequality holds for it.

math.DG↗

arXiv2019

Self-Adjoint Extensions of Bipartite Hamiltonians

We compute the deficiency spaces of operators of the form $H_A{\hat{\otimes}} I + I{\hat{\otimes}} H_B$, for symmetric $H_A$ and self-adjoint $H_B$. This enables us to construct self-adjoint extensions (if they exist) by means of von Neumann's theory. The structure of the deficiency spaces for this case was asserted already by Ibort, Marmo and P\'erez-Pardo, but only proven under the restriction of $H_B$ having discrete, non-degenerate spectrum.

math.FA↗