activity
20242026
collaborators

8 papers

gr-qc2026

The Hawking Singularity Theorem for Hölder Continuous Metrics with -Bounded Curvature

Michael Kunzinger, Moritz Reintjes, Roland Steinbauer +1

We prove a low-regularity version of Hawking's singularity theorem for Lorentzian metrics in with Riemann curvature in , where and the dimension of spacet…

math.DG2026

Distributional sectional curvature bounds for Riemannian metrics of low regularity

Darius Erös, Michael Kunzinger, Argam Ohanyan +1

Sectional curvature bounds are of central importance in the study of Riemannian manifolds, both in smooth differential geometry and in the generalized synthetic setting of Alexandr…

math.DG2026

Timelike conjugate points in Lorentzian length spaces

James D. E. Grant, Michael Kunzinger, Argam Ohanyan +2

We study notions of conjugate points along timelike geodesics in the synthetic setting of Lorentzian (pre-)length spaces, inspired by earlier work for metric spaces by Shankar--Sor…

math.DG2025

Hawking's singularity theorem for Lipschitz Lorentzian metrics

Matteo Calisti, Melanie Graf, Eduardo Hafemann +2

We prove Hawking's singularity theorem for spacetime metrics of local Lipschitz regularity. The proof rests on (1) new estimates for the Ricci curvature of regularising smooth metr…

math.DG2025

Ricci curvature bounds and rigidity for non-smooth Riemannian and semi-Riemannian metrics

Michael Kunzinger, Argam Ohanyan, Alessio Vardabasso

We study rigidity problems for Riemannian and semi-Riemannian manifolds with metrics of low regularity. Specifically, we prove a version of the Cheeger-Gromoll splitting theorem \c…

math.FA2025

On the completeness of the space

Michael Kunzinger, Norbert Ortner

We give a new proof of the completeness of the space by applying a criterion of compact regularity for the isomorphic sequence space $\lim_{k\rightarrow} (s\hat \ot…