▸ Drawing notation: fermion (arrow) · photon (wave) · gluon (coil)…

▸ Building interaction vertices — conserving charge & momentum

▸ Loading processes: Møller · Compton · pair annihilation/production · β decay…

▸ Note: a diagram = a CALCULATION TOOL, not a real trajectory

▸ Calibrating the light pulse along the lines — Online. ✅