Holomorphic Picard group (source code)

= Holomorphic Picard group
{title2=$\operatorname{Pic}_{\rm hol}(X)=H^1(X,\mathcal O_X^*)$}

= Analytic Picard group
{synonym}

The <holomorphic Picard group> consists of isomorphism classes of <holomorphic line bundles>, with <tensor product> as its group law. The trivial bundle is the identity and dualization gives inverses. Transition functions identify it with $H^1(X,\mathcal O_X^*)$. On the <complex projective line> every class is $\mathcal O(n)$, so degree gives an isomorphism with $\mathbb Z$.