# module-theory-eye-catch

by Yu · Published · Updated

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- Eckmann–Hilton Argument: Group Operation is a Group Homomorphism Let $G$ be a group with the identity element $e$ and suppose that we have a group homomorphism $\phi$ from the direct product $G \times G$ to $G$ satisfying \[\phi(e, g)=g \text{ and } \phi(g, e)=g, \tag{*}\] for any $g\in G$. Let $\mu: G\times G \to G$ be a map defined […]
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