Denis Bykov
2026
Diffusion-Pretrained Dense and Contextual Embeddings
Sedigheh Eslami | Maksim Gaiduk | Markus Krimmel | Louis Mark Milliken | Bo Wang | Denis Bykov
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (ACL 2026)
Sedigheh Eslami | Maksim Gaiduk | Markus Krimmel | Louis Mark Milliken | Bo Wang | Denis Bykov
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (ACL 2026)
We introduce pplx-embed, a family of multilingual embedding models that employ multi-stage contrastive learning on a diffusion-pretrained language model backbone for web-scale retrieval.By leveraging bidirectional attention through diffusion-based pretraining, our models capture comprehensive bidirectional context within passages, enabling the use of mean pooling to better preserve global context across long documents.We release pplx-embed-v1 for standard retrieval, and pplx-embed-context-v1 for contextualized embeddings that incorporate global document context into passage representations.pplx-embed-v1 achieves competitive performance on the MTEB(Multilingual, v2), MTEB(Code), BERGEN, and ToolRet retrieval benchmarks, while pplx-embed-context-v1 sets new records on the ConTEB benchmark.