Hopf theory MOC Tensor product H-module Let H be a Hopf K-algebra and 𝑅,𝐵 be H-modules. Then the K-tensor product 𝑅 ⊗K𝐵 of the underlying K-modules has a canonical H-module structure via the action #m/def/hopf 𝑥(𝑣⊗𝑤)=∑(𝑥)𝑥(1)𝑣⊗𝑥(2)𝑤 or string diagramatically #state/tidy | #lang/en | #SemBr