Belief propagation simplification

This lecture covers the simplification of the belief propagation equations for pairwise models, focusing on reducing the computational complexity from order n cubed to order n. The instructor explains the process of introducing auxiliary fields to rewrite the message passing functions, leading to a significant reduction in the number of computations required. The lecture also delves into the concept of effective magnetic fields and the transformation of the petition function using these new variables, providing a detailed walkthrough of the mathematical derivations and simplifications involved.