Platonic Task Arithmetic
This study addresses the limitation that task arithmetic among heterogeneous models cannot be transferred across architectures. To overcome this, it proposes a “Platonic” universal task descriptor that abstracts model-specific updates into architecture-agnostic shared representations. By integrating matrix operations, least-squares optimization, and Low-Rank Adaptation (LoRA), the method enables label-free cross-model task knowledge editing and linear composition. Extensive evaluations across six model families and eight tasks demonstrate that the proposed cross-architecture transfer preserves 74%–80% of the performance gains achieved by target models independently. These results indicate that the approach effectively overcomes the architectural barriers inherent in conventional task arithmetic, facilitating robust and flexible knowledge sharing among structurally diverse foundation models without requiring labeled data.