I am interested in computing the integral of this function:
\begin{align}
\int_0^\infty\frac{2du(u^2+1)}{(1-e^{2\pi u})},
\end{align}
which of course at first sight, does not converge. But in QFT it's usually possible to regulate such a function. Thus, the question is, does anyone know how to regulate this function?
This post imported from StackExchange Physics at 2014-04-13 12:28 (UCT), posted by SE-user tanzhongm