arXiv AI

Learning Pseudo-Riemannian Manifolds for Heterophilic Graphs via Graph Signature

The paper introduces the Graph Signature Index to quantify the mismatch between positive-definite geometric priors in many Graph Neural Networks and the negative distances often needed for heterophilic graphs. Using this signature, the authors propose the Pseudo‑Riemannian Attention Network (PRAT), which learns a signed squared pseudo‑distance metric that can capture both attractive and repulsive relationships. Experiments on fifteen node‑classification benchmarks show that PRAT matches or surpasses state‑of‑the‑art heterophily‑adapted models, and ablation studies confirm that the sign structure provided by the signature is essential for its performance.

arXiv Machine Learning
Jul 27

Local-Global Geometric Insights for Graph Neural Networks via Entropic Curvature

arXiv:2607. 22381v1 Announce Type: new Abstract: Curvature notions on graphs, particularly Ollivier-Ricci and Forman, have emerged as powerful tools for addressing fundamental issues in Graph Neural Networks (GNNs) such as oversmoothing and oversquashing, but rely almost exclusively on local edge-level comparisons and therefore fail to certify how information actually propagates over long distances.

By Rachid Caich, Yassine Abbahaddou
arXiv Machine Learning
Aug 19

HyPE-GT: where Graph Transformers meet Hyperbolic Positional Encodings

HyPE-GT introduces a framework that generates learnable hyperbolic positional encodings for Graph Transformers, enabling the capture of complex hierarchical relationships in graph-structured data. Unlike traditional Euclidean encodings, HyPE’s hyperbolic encodings can be selected to suit specific downstream tasks and help mitigate oversmoothing in deep Graph Neural Networks. Experiments on molecular benchmarks and large-scale Open Graph Benchmark datasets demonstrate improved performance, while additional tests on Coauthor and Copurchase networks confirm HyPE’s effectiveness in controlling oversmoothing.

By Kushal Bose, Swagatam Das
arXiv AI
Jul 24

Riemannian Deep Learning: Modules, Networks, and Geometries

arXiv:2607. 19305v2 Announce Type: replace-cross Abstract: Deep neural networks on manifold-valued representations have attracted growing interest, but many basic components remain tied to specific manifolds, rely on Euclidean approximations, or require costly and numerically fragile geometric operations.

By Chen Ziheng
arXiv AI
Jul 22

Riemannian Deep Learning:Modules, Networks, and Geometries

arXiv:2607. 19305v1 Announce Type: cross Abstract: Deep neural networks on manifold-valued representations have attracted growing interest, but many basic components remain tied to specific manifolds, rely on Euclidean approximations, or require costly and numerically fragile geometric operations.

By Chen Ziheng
arXiv Machine Learning
Jun 25

Towards Robust EEG Decoding Based on Riemannian Self-Attention

arXiv:2606. 25456v1 Announce Type: new Abstract: Brain-Computer Interface (BCI) based on electroencephalography (EEG) enables direct interaction between the brain and external environments and has significant applications in assistive technologies, medical rehabilitation, and entertainment.

By Shaocheng Jin, Tao Zhou, Rui Wang, Ziheng Chen, Xiaoqing Luo, Xiaojun Wu, Josef Kittler
arXiv Machine Learning
Oct 21

Learning Normal Coordinates on Riemannian Manifolds with Flow Charts

The paper introduces flow charts, a conditional invertible neural network designed to approximate normal coordinates on Riemannian manifolds, enabling fast Euclidean approximations of exponential and logarithmic maps. It presents a novel nonnegative loss function that is zero exactly when the chart is normal, and demonstrates that flow charts match or surpass specialized neural geodesic interpolators across sixteen synthetic and data‑derived geometries. When pretrained, flow charts achieve a median 60–70× speedup over numerical baselines while maintaining comparable logarithmic map estimation error and improving numerical geodesic solver accuracy.

By Edmond Cunningham
arXiv Machine Learning
Oct 9

SPD-MetaFormer is what you need for small-data brain decoding

The paper introduces SPD-MetaFormer, an attention‑free architecture for decoding brain signals from small datasets. It shows that existing attention‑based models on the SPD manifold (MAtt and GBWAtt) learn nearly uniform weights, and that replacing learned weights with uniform ones does not degrade performance. SPD-MetaFormer uses uniformly weighted Fréchet aggregation with a geodesic residual and a shared spectral feedforward map, achieving competitive results on three EEG benchmarks while maintaining SPD‑valued token states until classification.

By Zhida Wang, Wei Lyu, Guo Yu, Sui Tang