Enter as an interface discipline

In the Enter calculus, destructive readout removes the measured quantum names from the live quantum context. A classical record and unmeasured quantum factors may survive CheungEnter,CheungPhilosophy,CheungEn09. We use the explicitly specified finite Born instrument below; we do not rederive Cheung's characterization theorem from abbreviated axiom names.

The distinctions are important:

• a classical record is not a surviving clock;

• agreement of outcome probabilities is weaker than agreement of complete residual instruments;

• a finite encoding is not automatically a field apparatus;

• a supplied causal geometry is not reconstructed by assigning locations to quantum names.

The geometric setting follows I-B CheungIB. The operational proofs use complete channels, including untouched references, in the usual finite-dimensional sense Watrous.