Back ground
I studied the proof of "$KT$ zero theorem" and "$KT\log T$" theorem in Edwards book. And I'm looking for other kind of evaluation of the number of zeros on the line.
Take $$ \sigma<\min\lbrace \Re\rho|\frac{1}{2}<\Re\rho<1,0\leqq\Im\rho\leqq T,\zeta(\rho)=0\rbrace $$
Define
$N_0(T)$ the number of zeros on the critical line
$S_0(T)$ the argument of $\zeta(s)$ measured along the path
$\sigma\rightarrow \sigma+iT\rightarrow \frac{1}{2}+iT$
so that
$$ N_0(T)=\frac{T}{2\pi}\log\frac{T}{2\pi}-\frac{T}{2\pi}+S_0(T)+O(1) $$
holds.
How can I evaluate $S_0(T)$ to get a result about the zeros.
In particular, Can we show that $S_0(T)$ change its sign infinitely as the argument $S(T)$ along the path $2\rightarrow 2+iT\rightarrow \frac{1}{2}+iT$.
More precisely, can I apply the technique of Selberg in the paper "Contributions to the theory of the Rieman zeta function" to evaluate $S_0(T)$ here?