Ricci curvature for metric-measure spaces via optimal transport

By J. Lott, Cédric Villani. 2004

1,520 citations recorded by the source corpus.

We dene a notion of a measured length space X having nonnegative N-Ricci curvature, for N 2 [1;1), or having1-Ricci curvature bounded below byK, forK2 R. The denitions are in terms of the displacement convexity of certain functions on the associated Wasserstein metric space P2(X) of probability measures. We show that these properties are preserved under measured Gromov-Hausdor limits. We give geometric and analytic consequences. This paper has dual goals. One goal is to extend results about optimal transport from the setting of smooth Riemannian manifolds to the setting of length spaces. A second goal is to use optimal transport to give a notion for a measured length space to have Ricci curvature bounded below. We refer to [11] and [44] for background material on length spaces and optimal transport, respectively. Further bibliographic notes on optimal transport are in Appendix F. In the present introduction we motivate the questions that we address and we state the main results. To start on the geometric side, there are various reasons to try to extend notions of curvature from smooth Riemannian manifolds to more general spaces. A fairly general setting is that of length spaces, meaning metric spaces (X;d) in which the distance between two points equals the inmum of the lengths of curves joining the points. In the rest of this introduction we assume that X is a compact length space. Alexandrov gave a good notion of a length space having \curvature bounded below by K", with K a real number, in terms of the geodesic triangles in X. In the case of a Riemannian manifold M with the induced length structure, one recovers the Riemannian notion of having sectional curvature bounded below by K. Length spaces with Alexandrov curvature bounded below by K behave nicely with respect to the GromovHausdor topology on compact metric spaces (modulo isometries); they form

Subfields: Applied Mathematics, Astronomy and Astrophysics, Geometry and Topology

View Paper: https://www.semanticscholar.org/paper/d46a36c513d2bd58b77e0fd54a27d86b09c4d67f

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Applied Mathematics

  1. Nicola Gigli
  2. Luigi Ambrosio
  3. Andrea Mondino
  4. Fabio Cavalletti
  5. Emanuel Milman
  6. Giuseppe Savar'e
  7. Filippo Santambrogio
  8. Shin-ichi Ohta

In Astronomy and Astrophysics

  1. Andrea Mondino
  2. Nicola Gigli
  3. Luigi Ambrosio
  4. Fabio Cavalletti
  5. Giuseppe Savar'e
  6. Karl‐Theodor Sturm
  7. Matthias Erbar
  8. Renjin Jiang

In Geometry and Topology

  1. Nicola Gigli
  2. Andrea Mondino
  3. Luigi Ambrosio
  4. Giuseppe Savar'e
  5. Fabio Cavalletti
  6. Emanuel Milman
  7. Filippo Santambrogio
  8. Matthias Erbar

Citations in the corpus