Meaning
The selected transport base specifies the contexts and changes of context for which the source supplies a meaningful physical comparison problem.
A context records finite demand, gauge and spacetime presentations, scale, and markings. Gauge, regional, and scale arrows remain separate, with orientation determined by their physical comparison slots. Mixed two-cells are included only where the source provides them.
Example (illustrative)
A geometric inclusion D⊆D′ can induce a restriction of reconstruction data from D′ back to D. The physical comparison arrow therefore need not point in the same direction as the geometric inclusion.
Scope and limits
A drawn arrow or square is not a certified physical passage. The selected base is not asserted to contain every conceivable change of context.
Source
GAT VIII — Indexed Admissible Distributors and Selected Cofinal Čech Transport in Semisimple Yang–Mills Theory. GAT VIII, Section 3.