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arXiv · 1509.08356

Strict singularity of a Volterra-type integral operator on $H^p$

Santeri Miihkinen
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Abstract

We prove that a Volterra-type integral operator $T_gf(z) = \int_0^z f(ζ)g'(ζ)dζ, \, z \in \mathbb D,$ defined on Hardy spaces $H^p, \, 1 \le p < \infty,$ fixes an isomorphic copy of $\ell^p,$ if the operator $T_g$ is not compact. In particular, this shows that the strict singularity of the operator $T_g$ coincides with the compactness of the operator $T_g$ on spaces $H^p.$ As a consequence, we obtain a new proof for the equivalence of the compactness and the weak compactness of the operator $T_g$ on $H^1$.

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Santeri Miihkinen. 2015-09-28. Strict singularity of a Volterra-type integral operator on $H^p$. https://arxiv.org/abs/1509.08356

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