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Ali Taghavi
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The answer to this question is yes. There is a complex polynomial vector field on $\mathbb{C}^2$ which has a complex limit cycle which does not intersect the real plane $im(z)=im(w)=0$.

Consider the differential equation $$\begin{cases}z'=w+(z^2+w^2-4i)\\ w'=-z+(z^2+w^2-4i) \end{cases}$$

The regular leaf $L: z^2+w^2=4i$ of this singular foliation does not intersect the real part of $\mathbb{C}^2$. This leaf, which is topologically a cylinder, has a non trivial holonomy. In fact we have more: there is a closed curve on this leaf whose corresponding holonomy map is a hyperbolic map:it is not tangent to the identity map. Here is the argument:

The hyperbolicity, hence non triviality, of the holonomy of this leaf is a consequence of Theorem 3.2 Page 333 of the paper: First Variation of Holomorphic forms and some applications.

Elaboration: The foliation is defined by $$\omega= (w+(z^2+w^2-4i))dw-(-z+(z^2+w^2-4i))dz=0$$

To apply the theorem 3.2 in the above paper we find a $1-$ form $\alpha$ which satisfies $d\omega=\omega \wedge \alpha$.

Represent the above $1$ form $\omega$ in the form $Pdw-Qdz$. Then for $\alpha=(P_z+Q_w)/(P^2+Q^2)(pdz+Qdw)$ we have $d\omega=\omega \wedge \alpha$. Note that $P^2+Q^2$ does not vanish on $L$

To compute this integral we parametrize the cylinder $L$ with
$$ \phi(t)= \begin{cases} z(t)=t+i/t\\w(t)=t/i-1/t \end{cases}$$ where $\phi$ is defined on $t\in \mathbb{C} \setminus \{0\}.$

A very simple computation shows that $\int_{S^1} \phi^* \alpha$ is non zero since we obtain a pole of order 1 at the origin. In fact the later integral is $\int_{S^1} 2(z(t)+w(t))dt$. So we have a non degenerate pole that is a Pole of order 1. so the integral does not vanish. so the leafd $L$ is hyperbolic. $\square$

Ali Taghavi
  • 356
  • 8
  • 31
  • 123