Now the whole curriculum cashes out. From the transformer primer: after LayerNorm, a token's hidden state is (approximately) a unit vector — a point on a hypersphere. Each layer does two things: attention pulls the token's vector toward the vectors of the tokens it listens to — structurally the Lohe coupling term from section 1, with the agreement-chosen wiring from section 2 — and the MLP stirs it internally; then LayerNorm re-projects to the sphere. Nudge, re-project. Nudge, re-project. A few dozen times.
So a token passing through a transformer traces a path on the sphere — a short trajectory, bent at every step by where its context sits. Where the path ends up is the meaning the model settled on; the bending along the way is the computation.
Here is the part that makes paths worth caring about. Meaning-space is not flat ground — it has watersheds. Two tokens can start almost on top of each other, feel the same context, follow the same rule — and end up in different places, because they started on opposite sides of a divide. A drop of rain an inch to the left of a ridge line reaches a different ocean.
Below, two tokens begin a couple of degrees apart, straddling the watershed between two context clusters. Watch them separate: slowly at first (the divide is a place of indecision — pulls nearly balanced), then decisively, each to its own basin. "Nearby words, different meanings, different destinations" stops being a metaphor and becomes a picture.
This module is the doorway to the most technical material on the site. The Transformers as Oscillators essay takes the identification seriously — attention's write-back as the coupling term, term by term — and measures its consequences on real models. The Physics of Mind §08 finds that the paths real tokens trace do not wander the whole hypersphere: they live on a surface of a few dimensions inside it. And §15 shows that two models trained separately lay their meaning out on that surface the same way, one rotation apart (primer 07 builds the rotation-group language for that). If you climbed the curriculum from primer 00 to here, you have every concept those chapters use.