Newman Tauberian theorem (source code)

= Newman Tauberian theorem
{c}
{title2=$\int_0^\infty f(t)\,dt=F(0)$}

For bounded locally integrable $f$ on the nonnegative real line, suppose its <Laplace transform> $F$ extends holomorphically to an open neighborhood of the closed right half-plane. Then the ordinary improper integral converges to $F(0)$. <Contour damping for bounded Laplace transforms> bounds the difference from the finite-interval transform by $2\|f\|_\infty/R$ in the limit for every radius $R$. Extension merely to the open right half-plane is insufficient, as the constant function and transform $1/z$ show.