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Let $\mathbb{D}$ denote the open unit disk in $\mathbb{C}$, let $\mathcal{A}\left(\mathbb{D}\right)$ denote the vector space of all complex-valued functions which are holomorphic on $\mathbb{D}$, and let $W$ (“the set of weights”) be the set of all continuous non-negative real-valued functions on $\left[0,1\right]\subseteq\mathbb{R}$ that vanish at $1$.

Now, for every $w\in W$, define: $${A}_{w}\left(\mathbb{D}\right)\overset{\textrm{def}}{=}\left\{ f\in\mathcal{A}\left(\mathbb{D}\right):\limsup_{r\uparrow1}\frac{w\left(r\right)}{2\pi}\int_{0}^{2\pi}\left|f\left(re^{i\theta}\right)\right|d\theta<\infty\right\}$$

$$p_{w}\left(f\right)\overset{\textrm{def}}{=}\limsup_{r\uparrow1}\frac{w\left(r\right)}{2\pi}\int_{0}^{2\pi}\left|f\left(re^{i\theta}\right)\right|d\theta,\textrm{ }\forall f\in\mathcal{A}_{w}\left(\mathbb{D}\right)$$

Then, letting $f\in\mathcal{A}\left(\mathbb{D}\right)$ be arbitrary, define: $$W\left(f\right)\overset{\textrm{def}}{=}\left\{ w\in W:p_{w}\left(f\right)<\infty\right\}$$

Finally, fix $f\in\mathcal{A}\left(\mathbb{D}\right)$. I would be very happy if the condition: $$p_{w}\left(f\right)=0\textrm{ }\forall w\in W\left(f\right)$$

implied that: $$\limsup_{r\uparrow1}\left|f\left(r\right)\right|=0$$ or, even better:

$$\sup_{\theta\in\mathbb{R}}\limsup_{r\uparrow1}\left|f\left(re^{i\theta}\right)\right|=0$$

(and hence, that $f$ is identically $0$ on $\mathbb{D}$, right?) but I don't know how to go about proving either of these. Any thoughts?

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    $\begingroup$ $f=1$ is a counterexample. (You'd have to drop the condition that $w(1)=0$, and then the conclusion is correct, from the classical theory of $H^1$.) $\endgroup$ Commented Nov 30, 2019 at 1:40
  • $\begingroup$ Unfortunately, the w(1)=0 condition is non-negotiable. What if I took $\mathcal{A}\left(\mathbb{D}\right)$ modulo the equivalence relation defined by $f\sim g$ whenever $f-g$ has a continuous (or, maybe $L^{p}$, for appropriate $p≥1$) extension to the unit circle? $\endgroup$
    – MCS
    Commented Nov 30, 2019 at 20:58
  • $\begingroup$ @ChristianRemling Also, could you provide me a reference for the classical Hardy Space result you mentioned? Thanks in advance! $\endgroup$
    – MCS
    Commented Nov 30, 2019 at 23:50
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    $\begingroup$ Any of the standard books on the subject will have this result, for example you could try Garnett, Duren, or Koosis. $\endgroup$ Commented Dec 1, 2019 at 20:46
  • $\begingroup$ Garnett, as in John Garnett? I had him as a professor in my undergraduate years. ^_^ $\endgroup$
    – MCS
    Commented Dec 1, 2019 at 22:09

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