From the 1 of 9 linked papers with an AI index.
4 papers · 1 filter
Lectures on Alexandrov spaces with curvature bounded below
Vitali Kapovitch, Nina Lebedeva, Anton Petrunin
This work is an introductory exposition on Alexandrov spaces with curvature bounded below, covering comparison conditions, the globalization theorem, tangent spaces, gradient flows…
Quadratic metric comparisons
Nina Lebedeva, Anton Petrunin, Vladimir Zolotov
We study the effects on length spaces imposed by quadratic inequalities on the six distances between the points in every quadruple.
Alexandrov meets Kirszbraun
Stephanie Alexander, Vitali Kapovitch, Anton Petrunin
We give a simplified proof of the generalized Kirszbraun theorem for Alexandrov spaces, which is due to Lang and Schroeder. We also discuss related questions, both solved and open.
Curvature tensor of smoothable Alexandrov spaces
Nina Lebedeva, Anton Petrunin
We prove weak convergence of curvature tensors of Riemannian manifolds for converging noncollapsing sequences with a lower bound on sectional curvature.