Low-temperature InfoNCE is the modality gap's cause

- With identical-initialization dual encoders that start perfectly overlapped, the InfoNCE loss actively separates the two modalities at low temperature, a mode failure rather than an initialization cone effect. [mager-etal-2026-on-the-modality-gap-and-the-contrastive-loss-in-multi-modal-representation-learning] - Adding intra-modal negatives (xNCE) prevents this separation across temperatures (MNIST modality-centroid distance 0.75 at tau=0.01 under InfoNCE vs ~0.09-0.13 under xNCE). [mager-etal-2026-on-the-modality-gap-and-the-contrastive-loss-in-multi-modal-representation-learning] - The gap is largely reduced rather than proven eliminated; the mechanism is supported by a theoretical analysis of the InfoNCE temperature term. [mager-etal-2026-on-the-modality-gap-and-the-contrastive-loss-in-multi-modal-representation-learning] - Real-model experiments use CLIP ViT-B/16 on MS-COCO, alongside a custom MNIST vision transformer that carries the mechanistic evidence. [mager-etal-2026-on-the-modality-gap-and-the-contrastive-loss-in-multi-modal-representation-learning]