Area of a quadratic differential
= Area of a quadratic differential
{title2=$\|q\|_1=\int_X|q|$}
= Quadratic differential area
{synonym}
The area of the <flat metric of a quadratic differential> is $\int_X|q|$. Multiplying $q$ by a scalar $a$ multiplies this area by $|a|$ and lengths by $|a|^{1/2}$. It is preserved by the <SL2R action on differentials>.