Pullback diagram of H*-algebras

In this paper we obtain some properties for the pullback diagram of H*-algebras. More precisely, we prove that the commutative diagram of H*-algebras and morphisms A1 @>j1>> B1 @VVy1V @VVy2V A2 @>j2>> B2 is pullback and y1 is an injection if and only if y1 is a surjection, y2 is an injection, and \ker j1 \cap \ker y1 = \{0\}.

Pullback diagram of H*-algebras

In this paper we obtain some properties for the pullback diagram of H*-algebras. More precisely, we prove that the commutative diagram of H*-algebras and morphisms A1 @>j1>> B1 @VVy1V @VVy2V A2 @>j2>> B2 is pullback and y1 is an injection if and only if y1 is a surjection, y2 is an injection, and \ker j1 \cap \ker y1 = \{0\}.

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