Abstract
We show convergence of the gradients of the Schrödinger potentials to the (uniquely determined) gradient of Kantorovich potentials in the small-time limit under general assumptions on the marginals, which allow for unbounded densities and supports. Furthermore, we provide novel quantitative stability estimates for the optimal values and optimal couplings for the Schrödinger problem (SP), that we express in terms of a negative order weighted homogeneous Sobolev norm. The latter encodes the linearized behavior of the 2-Wasserstein distance between the marginals. The proofs of both results highlight for the first time the relevance of gradient bounds for Schrödinger potentials, that we establish here in full generality, in the analysis of the short-time behavior of Schrödinger bridges. Finally, we discuss how our results translate into the framework of quadratic Entropic Optimal Transport, that is a version of SP more suitable for applications in machine learning and data science.
Original language | English |
---|---|
Pages (from-to) | 895-943 |
Number of pages | 49 |
Journal | Communications in Partial Differential Equations |
Volume | 48 |
Issue number | 6 |
DOIs | |
Publication status | Published - 2023 |
Bibliographical note
Funding Information:While this work was written, AC was associated to INdAM and the group GNAMPA. GC acknowledges funding from the grant SPOT (ANR-20-CE40-0014). GG acknowledges support from NWO Research Project 613.009. “Analysis meets Stochastics: Scaling limits in complex systems.” LT acknowledges support from the PRIN 2017 (Prot. 2017TEXA3H) “Gradient flows, Optimal Transport and Metric Measure Structures.”
Funding Information:
This study was funded by Agence Nationale de la Recherche; Ministero dell’Istruzione, dell’Università e della Ricerca; Nederlandse Organisatie voor Wetenschappelijk Onderzoek. While this work was written, AC was associated to INdAM and the group GNAMPA. GC acknowledges funding from the grant SPOT (ANR-20-CE40-0014). GG acknowledges support from NWO Research Project 613.009. “Analysis meets Stochastics: Scaling limits in complex systems.” LT acknowledges support from the PRIN 2017 (Prot. 2017TEXA3H) “Gradient flows, Optimal Transport and Metric Measure Structures.”
Funding
While this work was written, AC was associated to INdAM and the group GNAMPA. GC acknowledges funding from the grant SPOT (ANR-20-CE40-0014). GG acknowledges support from NWO Research Project 613.009. “Analysis meets Stochastics: Scaling limits in complex systems.” LT acknowledges support from the PRIN 2017 (Prot. 2017TEXA3H) “Gradient flows, Optimal Transport and Metric Measure Structures.” This study was funded by Agence Nationale de la Recherche; Ministero dell’Istruzione, dell’Università e della Ricerca; Nederlandse Organisatie voor Wetenschappelijk Onderzoek. While this work was written, AC was associated to INdAM and the group GNAMPA. GC acknowledges funding from the grant SPOT (ANR-20-CE40-0014). GG acknowledges support from NWO Research Project 613.009. “Analysis meets Stochastics: Scaling limits in complex systems.” LT acknowledges support from the PRIN 2017 (Prot. 2017TEXA3H) “Gradient flows, Optimal Transport and Metric Measure Structures.”
Keywords
- Curvature lower bounds
- entropic regularization
- gradient estimates
- optimal transport
- quantitative stability
- Schrödinger potentials
- Schrödinger problem