Graph neural network (GNN)
Beginner
A kind of learning program that works on networks of connected things, like the parts and wires of a circuit.
Novice
A neural network that works on a network of connected items. It keeps a short list of numbers for each item and updates it from its neighbors’ lists, round after round. A circuit fits naturally: gates are the items and wires are the connections.
Expert
Each layer passes messages along the edges, so after L layers a node has information from L hops away. Timing models often update nodes in signal order. Errors can build up along long paths, and graphs with millions of gates have to be split up to fit in GPU memory.