3 papers
math.DG2026
Total curvature and length estimates for timelike curves in Lorentzian length spaces
Darius Erös, Felix Rott, Zhe-Feng Xu
We introduce and study a synthetic notion of timelike total curvature for curves in Lorentzian length spaces with upper curvature bounds. In particular, we prove that our notion ag…
math.FA2026
-Caffarelli--Kohn--Nirenberg inequalities on metric measure spaces
Zhe-Feng Xu, Ye Zhang
Motivated by the sharp constants in the -Caffarelli--Kohn--Nirenberg (or -CKN for short) inequalities on Euclidean spaces, we study, in a unified framework, a sequence of…
math.DG2026
Lorentz meets Ptolemy
Felix Rott, Zhe-Feng Xu, Matteo Zanardini
We consider a Lorentzian analogue of the Ptolemy inequality and we prove that in the setting of globally hyperbolic spacetimes it is equivalent to a global timelike sectional curva…