3 papers
math.DG2026
Generalized cones admitting a curvature-dimension condition
Matteo Calisti, Christian Ketterer, Clemens Sämann
We study (generalized) cones over metric spaces, both in Riemannian and Lorentzian signature. In particular, we establish synthetic lower Ricci curvature bounds à la Lott-Villani-S…
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
A nonlinear d'Alembert comparison theorem and causal differential calculus on metric measure spacetimes
Tobias Beran, Mathias Braun, Matteo Calisti +5
We introduce a variational first-order Sobolev calculus on metric measure spacetimes. The key object is the maximal weak subslope of an arbitrary causal function, which plays the r…