Theorem: One complete four-face exchange

In the fixed cone with $\mu =\pi /2$, the capped slicing eq:capped has exactly one central four-face exchange on $[-1,1]$, with:

1. spacelike time-ordered slices and transverse central edge laws;

2. explicit adapted affine charts and exact local words;

3. certified event germs and an exact $s=0$ guard;

4. a compact collar matching one fixed exterior cellulation;

5. abstract transport using declared location labels;

6. spectator-blind control under separate storage reservation;

7. an exact finite decoder-correct event implementation on its declared code family.

The resting particle has, on both sides,

Proof. The geometric claims are prop:R1,prop:R2,prop:R3,prop:R4,prop:R5,prop:R6, prop:cap,prop:collarproducts,prop:R8,prop:alllengths. Control and transport are prop:Gcertificate; decoding and realization are prop:decoder,prop:circuit. The particle word and resting normal are unchanged.