リボン圏の一貫性

Bruce Bartlett の "Categorical Aspect of TQFTs"(TQFTはフルスペル) より：

Theorem (Reshetikhin and Turaev [89]).

Let (C,×, 1, σ, θ) be a ribbon category. Then the evaluation of a ribbon diagram into a morphism in C is invariant under 3d isotopy.

In other words, the graphical calculus in terms of ribbons is entirely consistent, and is a powerful way to do computations inside ribbon categories : simply deform the diagrams appropriately.

これは一貫性だろう。