OCE erases diffusion concepts via a shared orthogonal rotation preserving norms and angles

Sun et al. edit a diffusion model's cross-attention key/value weights in place via a single shared orthogonal matrix P solved in closed form from an orthogonal Procrustes problem [sun-etal-2026-orthogonal-concept-erasure-for-diffusion-models] Because P is orthogonal, neuron magnitudes and pairwise inter-neuron angles are preserved exactly, an algebraic guarantee rather than a measured statistic [sun-etal-2026-orthogonal-concept-erasure-for-diffusion-models] An ablation shows the design matters: additive scaling has negligible effect, layer-wise shared rotation gives a clean semantic shift, and neuron-wise rotation degrades image quality [sun-etal-2026-orthogonal-concept-erasure-for-diffusion-models] It erases object classes, styles, up to 100 celebrities simultaneously, and NSFW content on SD v1.4, transferring zero-shot to the DiT-architecture FLUX.1 [sun-etal-2026-orthogonal-concept-erasure-for-diffusion-models]