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Let $\mathbb{D}\subset \mathbb{C}$ denote the unit disk.

I would like to seek sufficient—and, if possible, necessary—conditions on a weight function $$\mu: \mathbb{D} \rightarrow (0,+\infty),\quad \mu \in C^1(\overline{\mathbb{D}}),$$ for which there exists a constant $\delta >0$ with the following property:

For every analytic function $h_1$ on $\mathbb{D}$, there exists an analytic function $h_2$ on $\mathbb{D}$ such that $$2 \text{Re} \int_{\mathbb{D}} h_1 \overline{h}_2 \geq \delta \int_{\mathbb{D}} |h_1|^2 \mu + \int_{\mathbb{D}} |h_2|^2 \frac{1}{\mu}.$$

It can be seen that the property holds when $\mu$ is a constant. I therefore expects it to remain valid for a broader class of weight functions.

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A slight generalization of the constancy of $\mu$ condition:

If $0<a\le\mu\le b$ for some real $a$ and $b$, take $\delta=a/b$ and then, for any $h_1$, take $h_2=ah_1$.

A more general idea is to take any $\delta\in(0,1)$ and assume that $\mu$ can be approximated well enough by an analytic function $g$ (which may be a polynomial), and then let $h_2:=h_1 g$. Then we will have $$2 \Re\int h_1 \overline{h}_2 \approx 2\int|h_1|^2\mu \approx \int |h_1|^2 \mu + \int |h_2|^2 \frac{1}{\mu} \\ \ge \delta \int |h_1|^2 \mu + \int |h_2|^2 \frac{1}{\mu},$$ with the condition $\delta<1$ hopefully allowing us to overcome the errors in the two approximate equalities.

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