The Multi-Vector Retrieval Index Paradox: How MUVERA Approximates Chamfer with Single-Vector ANN
·2172 words·11 mins
Models like ColBERT and ColPali represent documents as token-level vector sets and pay for finer alignment with late interaction (MaxSim/Chamfer)—but index entries explode from one per document to hundreds. Google Research’s MUVERA compresses each set into a single fixed-dimensional encoding for one ANN pass, then reranks with true Chamfer; this article separates paper facts from podcast opinion for engineers shipping multi-vector search.