The Indra Representation Hypothesis for Multimodal Alignment
This work provides a theoretically grounded, training-free framework for improving alignment in multimodal AI systems, addressing a foundational challenge in machine learning.
The paper tackles the problem of limited expressiveness in unimodal foundation models by proposing the Indra Representation Hypothesis, which posits that these models converge to a shared relational structure, and demonstrates that Indra representations enhance robustness and alignment across architectures and modalities in cross-model and cross-modal scenarios.
Recent studies have uncovered an interesting phenomenon: unimodal foundation models tend to learn convergent representations, regardless of differences in architecture, training objectives, or data modalities. However, these representations are essentially internal abstractions of samples that characterize samples independently, leading to limited expressiveness. In this paper, we propose The Indra Representation Hypothesis, inspired by the philosophical metaphor of Indra's Net. We argue that representations from unimodal foundation models are converging to implicitly reflect a shared relational structure underlying reality, akin to the relational ontology of Indra's Net. We formalize this hypothesis using the V-enriched Yoneda embedding from category theory, defining the Indra representation as a relational profile of each sample with respect to others. This formulation is shown to be unique, complete, and structure-preserving under a given cost function. We instantiate the Indra representation using angular distance and evaluate it in cross-model and cross-modal scenarios involving vision, language, and audio. Extensive experiments demonstrate that Indra representations consistently enhance robustness and alignment across architectures and modalities, providing a theoretically grounded and practical framework for training-free alignment of unimodal foundation models. Our code is available at https://github.com/Jianglin954/Indra.