Friedrich Bauermeister

collaborators

4 papers

math.DG2026

Refocusing spacetimes need not be strongly refocusing

Friedrich Bauermeister

We prove that there are globally hyperbolic spacetimes which are refocusing but not strongly refocusing. In fact, every globally hyperbolic strongly refocusing spacetime of dimensi…

math.DG2026

Topological consequences of null-geodesic refocusing and applications to $Z^{x}$ manifolds

Friedrich Bauermeister

Let $(M, h)$ be a connected, complete Riemannian manifold, $x \in M$ , and $l > 0$ . Then $M$ is called a $Z^{x}$ manifold if all geodesics starting at $x$ return to $x$ , and it is called…

math.GT2025

Gordian split links in the Gehring ropelength problem

Friedrich Bauermeister

A thick link is a link in $R^{3}$ such that each component of the link lies at distance at least $1$ from every other component. Strengthening the notion of thickness, a thi…

math.CO2025

Strata of toric hyperplane arrangements, zonotope lattice points, and the Bondal-Thomsen collection

Friedrich Bauermeister, Andrew Hanlon, Davis Painter +2

We show that strata of oriented toric hyperplane arrangements are in bijection with a collection of lattice points in a zonotope. Moreover, we relate the dimension of the stratum a…

Refocusing spacetimes need not be strongly refocusing

Topological consequences of null-geodesic refocusing and applications to Zx manifolds

Gordian split links in the Gehring ropelength problem

Strata of toric hyperplane arrangements, zonotope lattice points, and the Bondal-Thomsen collection

Topological consequences of null-geodesic refocusing and applications to $Z^{x}$ manifolds