By truncating the Fourier transform, Pólya managed to prove that the Xi function on the critical line was approximately
$\xi(1/2+is) = (2\pi)^2 ( K_{9/4+is/2}( 2\pi) +K_{9/4-is/2}( 2\pi))$
If this approximation is valid, why is it not considered that Pólya solved RH??