On the Tensor Products in Som e Subcategories of Semigroups

Abstract:

      In this paper the existence and uniqueness of tensor product in any semigroup variety are proved, and the relation between the tensor products in semigroup variety and in semigroup category is charaterized. Next, we consider the existence and uniqueness of tensor product in cancellation commutative semigr-oup subcategory, this tensor product is a subsemigroup of tensor product of two quotient groups in abelian group category.