J-lens CKA explorer
Every cell is the CKA between two layers’ J-lens token geometries — within one model or across two. Probes: 4,096 token strings shared by all 38 tokenizers, each model reading them through its own unembedding. Family and size chips are toggles that combine (several families × a size range); checkboxes fine-tune. At every layer, each vocabulary token has a steering direction — its J-lens vector, the direction in activation space that pushes the model toward eventually saying that token. Each cell of the matrix asks: do two layers arrange those 4,096 directions the same way? 1.0 = identical geometry, 0 = unrelated. Blocks are models. Bright squares on a model’s own diagonal are stretches of layers holding one geometry — the paper’s sensory / workspace / motor regions. A bright 45° band in a cross block means two models organize the vocabulary the same way at the same fraction of depth. Red outlines frame the diagonal region of each sub-family (gemma-2 / gemma-3 / qwen3 / qwen3.5 …, or ea