Manuscript En03-A@1 · En03-A.tex · proof · 5398614e
Proof
Kinematics and causal cuts on a prescribed schedule › The channel causal-cut criterion · lines 808–814
Proof. Choose a reverse topological ordering. Pull an observable on back through each box. If it is identity on all outputs of a box, unitality leaves identity on all inputs. Otherwise its possible support is enlarged to that box's input interface. Induction gives eq:network-cut. Apply ip:nosignal.