DeepSeek researchers have addressed instability issues in large language model training by applying a 1967 matrix normalization algorithm to hyper connections. Hyper connections, which enhance the expressivity of models by widening the residual stream, were found to cause instability at scale due to excessive amplification of signals. The new method, Manifold Constrained Hyper Connections (mHC), projects residual mixing matrices onto the manifold of doubly stochastic matrices using the Sinkhorn-Knopp algorithm, ensuring numerical stability by maintaining controlled signal propagation. This approach significantly reduces amplification in the model, leading to improved performance and stability with only a modest increase in training time, demonstrating a new axis for scaling large language models. This matters because it offers a practical solution to enhance the stability and performance of large AI models, paving the way for more efficient and reliable AI systems.
