I am looking for an example of an analytic map $f$ on the complex domain for which there exist $r>0$ such that for $\gamma=\{z:|z|=r\}$, a.s. for $\theta \in [0,2\pi)$ we have that $$\int_{f(\gamma)} \frac{1}{2 \pi i} \frac{dw}{w} < \left( f(\gamma)e^{-2\pi i \theta}\cap \mathbb{R}_{+} \right).$$
1 Answer
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For $r=1$, the function $f(z) = (z+\sqrt2)^4$ works nicely. The path integral equals $0$, while the count on the right-hand side is always at least 1. (In fact, if you reduce $\sqrt2$ slightly, you can get the count to be at least 2 always.)
To deduce how I came up with this function, consider it as the composition of $z\mapsto z+\sqrt2$ with $z\mapsto z^4$, and think about what each map does to the complex plane.
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$\begingroup$ Thanks, I was looking for this because I wanted to convince myself that the problem of counting complex zeros cannot be such an easy reduced from counting real zeros. $\endgroup$– UmbertoCommented Feb 20, 2013 at 13:44