SpectralShift extends Gated DeltaNet context windows via spectral reparameterization

RUC-AIBOX · hf · 2026-09-17

Linear attention layers are increasingly replacing softmax attention for long-context modeling, yet existing context-extension methods keep continued pretraining without modifying these layers, ignoring the spectral properties of linear attention state dynamics. The RUC team studies long-context extension of Gated DeltaNet (GDN) through the spectrum of its transition matrix, identifying two key factors: a sufficiently broad slow spectral band aligned with target dependency length, and preservation of fast-decaying modes for state clearing and context switching.

They propose SpectralShift, which reparameterizes alpha-projection initialization to reshape the decay spectrum and enhance slow propagation, plus a learning-rate scaling for alpha projections to ease long-context training. Experiments show consistent long-context gains over training, offering an effective, efficient way to extend context windows of linear attention models. Code is open-sourced on GitHub.

Original post →

More from Research

Research channel →