4 papers
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…
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…
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…
Timelike Ricci bounds for low regularity spacetimes by optimal transport
Mathias Braun, Matteo Calisti
We prove that a globally hyperbolic smooth spacetime endowed with a -Lorentzian metric whose Ricci tensor is bounded from below in all timelike directions, in…