While many Machine Learning methods were developed or transposed on Riemannian manifolds to tackle data with known non Euclidean geometry, Optimal Transport (OT) methods on such spaces have not received much attention. The main OT tool on these spaces is the Wasserstein distance which suffers from a heavy computational burden. On Euclidean spaces, a popular alternative is the Sliced-Wasserstein distance, which leverages a closed-form solution of the Wasserstein distance in one dimension, but which is not readily available on manifolds. In this work, we derive general constructions of Sliced-Wasserstein distances on Cartan-Hadamard manifolds, Riemannian manifolds with non-positive curvature, which include among others Hyperbolic spaces or the space of Symmetric Positive Definite matrices. Then, we propose different applications. Additionally, we derive non-parametric schemes to minimize these new distances by approximating their Wasserstein gradient flows.

在这份研究论文中，我们探讨了在已知非欧几里德几何特性的数据上，机器学习方法在黎曼流形上的应用以及最优输运方法在该领域的研究。我们提出了在卡尔曼-哈达玛德流形上的分片瓦砾斯坦距离，该方法在欧几里德空间上具有闭合解，并且我们还探索了该方法在其他几何空间的应用，以及近似计算其瓦砾斯坦梯度流的非参数方案。

Cartan-Hadamard流形上的切片Wasserstein距离和流动