HGMem: Hypergraph Memory for Multi-step RAG
Chulun Zhou, Chunkang Zhang, Guoxin Yu, Fandong Meng, Jie Zhou, Wai Lam, Mo Yu•Dec 2025
Information RetrievalLarge Language ModelsKnowledge Graphs
Standard RAG systems store facts as isolated items, losing the connections between them. HGMem represents memory as a hypergraph where 'hyperedges' connect multiple related facts into composite units. On sense-making tasks requiring integration of scattered evidence, HGMem achieves up to 10% accuracy gains over strong baselines like DeepRAG and LightRAG.
Solves the 'scattered evidence' problem: when answers require connecting facts from different sections of a 200-page document, standard RAG fails but HGMem succeeds