Message Passing Neural Network
Message Passing Neural Networks (MPNNs) are a class of graph neural networks that iteratively update node representations by aggregating information from neighboring nodes, aiming to learn complex functions over graph-structured data. Current research focuses on addressing limitations such as over-squashing (information loss during aggregation) and over-smoothing (loss of node distinctiveness), often through architectural innovations like incorporating virtual nodes, hierarchical structures, or alternative aggregation schemes, and exploring the use of untrained layers. MPNNs are proving valuable across diverse fields, including knowledge graph reasoning, link prediction, and material science, by enabling efficient and effective learning from complex relational data.