Xianglong Shi

Author directory

2026

Neural networks over non-Euclidean manifolds have attracted increasing attention across various applications. A fundamental step in these networks is to map Euclidean features onto a target manifold. Existing methods mainly use exponential maps and projections, operate through tangent or ambient Euclidean spaces, and may therefore distort intrinsic manifold geometry. On the other hand, point-to-hyperplane distances have recently shown great success in building manifold-valued networks. Based on this, we propose the Point-to-Hyperplane Distance Map (PHDM), a parameter-free mapping that extends Euclidean fully connected layers to Euclidean-to-manifold transformations. Specially, the exponential map is recovered as a pseudo-distance-based special case. We manifest PHDM on the Lorentz, Poincaré, spherical, and projected-spherical models, covering both negative and positive curvature. Experiments on arithmetic reasoning across four LLMs, image classification, graph node classification, and link prediction demonstrate consistent improvements over the corresponding baselines. The code is available at https://github.com/Longchentong/PHDM.