English
Under pushout, the equivalence respects tensed pure tensors: (a ⊗ b) maps to algebraMap a times algebraMap b.
Русский
При пушауте равенство на простых тензорных базисах сохраняется: (a ⊗ b) → algebraMap(a) · algebraMap(b).
LaTeX
$$equiv_tmul (a) (b) = algebraMap _ _ a * algebraMap _ _ b$$
Lean4
instance isPushout {R S T : Type*} [CommSemiring R] [CommSemiring S] [CommSemiring T] [Algebra R S] [Algebra R T] :
Algebra.IsPushout R S T (S ⊗[R] T) :=
⟨TensorProduct.isBaseChange R T S⟩