A nontrivial finite target through the event

Let $o$ be the cone apex and choose the persistent ray mark

Set

Place one input qubit at each of $p_o(-h_{\ast })$ and $p_e(-h_{\ast })$. The independent target is:

1. update the local event code by its specified $U_{\mathrm{code}}$;

2. exchange the two quantum states at the output ports $p_o(h_{\ast })$, $p_e(h_{\ast })$;

3. retain code history and return clean work.

Thus its matter channel is ${\mathrm{Ad}}_{\mathrm{SWAP}}$, not the identity. This is a declared discrete carrier target, not an Einstein or scalar-field evolution.

The encoding is the identity on each input qubit, with local clean code/work initialization. The decoding reads the returned target factors and the declared event record; it has no nonlocal preprocessing.