Frieder Jackel

collaborators

3 papers

math.AP2026

Constant potentials do not minimize the fundamental gap on convex domains in negatively curved Hadamard manifolds

Frieder JÃ¤ckel

We show that for every negatively curved Hadamard manifold $X$ and every $D > 0$ there exists a convex domain $I^c ◯ \subseteq X$ with diameter $D$ and a convex potential $V$ on $I^c ◯$ s…

math.AP2025

Constant potentials do not minimise the fundamental gap on convex domains in hyperbolic space

Julie Clutterbuck, Frieder JÃ¤ckel, Xuan Hien Nguyen

We show that for every $n \geq 2$ and $D > 0$ there exist a convex domain $I^c ◯ \subseteq H^{n}$ with diameter $D$ and a convex potential $V$ on $I^c ◯$ such that the fundamental g…

math.DG2025

Negatively curved Einstein metrics on Gromov-Thurston manifolds

Ursula HamenstÃ¤dt, Frieder JÃ¤ckel

For every $n \geq 4$ we construct infinitely many mutually not homotopic closed manifolds of dimension $n$ which admit a negatively curved Einstein metric but no locally symmetric m…