Let $G \le GL(n,\mathbb C)$ be a matrix Lie group, where this means that $G$ is a closed subgroup of $GL(n,\mathbb C)$ in the [subspace topology](/page/Subspace%20Topology) inherited from $M(n,\mathbb C)$. Then $G$ admits a smooth structure for which $G$ is an embedded submanifold of the open manifold $GL(n,\mathbb C)$. Consequently, through the open inclusion $GL(n,\mathbb C)\subset M(n,\mathbb C)$, the group $G$ is also an embedded submanifold of the real [vector space](/page/Vector%20Space) $M(n,\mathbb C)$. With this smooth structure, the multiplication map
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\begin{align*}
m_G:G\times G\to G,\quad (A,B)\mapsto AB
\end{align*}