Holomorphic one-form
= Holomorphic one-form
{title2=$\omega\in H^0(X,K_X)$}
= Abelian differential
{c}
{synonym}
A section $\omega$ of the <canonical bundle> of a <Riemann surface>, locally $\omega=\phi(z)\,dz$ with <holomorphic> $\phi$. A nonzero form on a <compact> <genus>-$g$ surface has total <zero order> $2g-2$. Its integral supplies <flat coordinates> away from zeros.