Three incoming arrows. Connect the centers last.
The new receiver shares face ABC with the proton tetrahedron. It does not receive another complete twelve-arrow structure. No belt is added.
12 old arrows + 3 incoming arrows
Blue: proton structure · Gold: three new incoming arrows · Green: shared face
Drag to rotate; scroll to zoom. In “Centers last,” hide the frames to see the segment representation.
A receiver, not a second proton
The old tetrahedron retains twelve directed arrows. Only A → e, B → e, and C → e are added. No primitive arrows leave e.
Three channels, one arrival value
ω³ = 1. The incoming maps remove the relative cyclic phases; all three images agree at e.
What fixes the geometry?
The three new edges inherit the original tetrahedron’s edge length. There are two points at that distance from A, B, and C: the old apex D and its reflection across ABC. The outward condition selects the reflected point e.
The phase compatibility does not determine this edge length. Equal-edge realization is the explicit geometric rule used here.
Only after building both tetrahedra do we compute their barycenters bP and bQ. Their connecting segment crosses ABC at its center F. The receiver apex e is not bQ. The segment is a higher-level representation; it is not counted as a sixteenth primitive arrow.
The display uses a rigid rotation and translation to put ABC horizontally. It does not shrink either complex or identify their centers.
Three-arrow compatibility calculation · Spatial construction