Stability of optimal transport maps and second variation of the 2-Monge-Kantorovich distance
Abstract
We establish several quantitative stability estimates for optimal transport maps between non-degenerate densities on uniformly convex domains for the quadratic cost. Under Hölder regularity assumptions, we prove Lipschitz L2 (respectively C0,α) stability estimates for optimal transport maps in terms of the $2$-Monge--Kantorovich distance (respectively Lp distances) between pairs of source and target densities. When the continuity assumption is removed, we obtain a Lipschitz L2 stability estimate for the Brenier potentials in terms of the L2 distance between the source and target densities. The proofs rely on a precise characterization of the linear response of the Brenier potential along smooth interpolations of the data, obtained by linearizing the Monge--Ampère equation in divergence form. As a further application of this approach, we derive an explicit formula for the second variation of the quadratic Monge--Kantorovich distance.
Related
- Stability of Kantorovich potentials via heat kernel regularization
- Stability of the Monge Map in Semi-Dual Optimal Transport
- Stability, discretization, and optimality of continuous-time causal optimal transport
- One-third Hölder stability of optimal transport maps from log-concave sources
- Optimal tradeoffs between variance and sensitivity, via Hellinger-Kantorovich geometry
BibTeX
@misc{cajalopez2026stability,
title = {{Stability of optimal transport maps and second variation of the 2-Monge-Kantorovich distance}},
author = {F. -U. Caja-Lopez and Matias G. Delgadino and Jun Kitagawa},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2605.24232},
eprint = {2605.24232},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2605.24232},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Stability of optimal transport maps and second variation of the 2-Monge-Kantorovich distance
AU - F. -U. Caja-Lopez
AU - Matias G. Delgadino
AU - Jun Kitagawa
PY - 2026
DA - 2026/10/19
PB - arXiv
DO - 10.48550/arxiv.2605.24232
UR - https://arxiv.org/abs/2605.24232
AB - We establish several quantitative stability estimates for optimal transport maps between non-degenerate densities on uniformly convex domains for the quadratic cost. Under Hölder regularity assumptions, we prove Lipschitz L^2 (respectively C^0,α) stability estimates for optimal transport maps in terms of the $2$-Monge--Kantorovich distance (respectively L^p distances) between pairs of source and target densities. When the continuity assumption is removed, we obtain a Lipschitz L^2 stability estimate for the Brenier potentials in terms of the L^2 distance between the source and target densities. The proofs rely on a precise characterization of the linear response of the Brenier potential along smooth interpolations of the data, obtained by linearizing the Monge--Ampère equation in divergence form. As a further application of this approach, we derive an explicit formula for the second variation of the quadratic Monge--Kantorovich distance.
ER -